diff options
| author | Jonathan Corbet <corbet@lwn.net> | 2016-10-25 18:05:23 -0600 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2016-10-25 18:05:23 -0600 |
| commit | 9e1f08607f904e89568e197f4e30985484a87fd7 (patch) | |
| tree | eb1e5388ce1d7f65302597c495f5b45b8b3d700e | |
| parent | bb118c56fda53fbca71ee8f35ff870d35370c969 (diff) | |
| parent | 3cbd4b543bef00c638fd63f6f043006c0c432f23 (diff) | |
| download | op-kernel-dev-9e1f08607f904e89568e197f4e30985484a87fd7.zip op-kernel-dev-9e1f08607f904e89568e197f4e30985484a87fd7.tar.gz | |
Merge branch 'mauro-books' into docs-next
Merge Mauro's massive patch series creating the process and admin-guide
books. I think there's a lot of stuff to clean up here, but there's no
point in holding things up for that.
Mauro sez:
This patch series continues the efforts of converting the Linux Kernel
documentation to Sphinx.
It contains text to ReST conversion of several files under Documentation,
and a few ones under the main dir (README, REPORTING-BUGS).
All patches on this series can be found on my development tree:
https://git.linuxtv.org/mchehab/experimental.git/log/?h=lkml-books-v2
The Kernel docs html output after this series can be seen at:
https://mchehab.fedorapeople.org/kernel_docs/
149 files changed, 6048 insertions, 5546 deletions
diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX index 3acc4f1..903ebc4 100644 --- a/Documentation/00-INDEX +++ b/Documentation/00-INDEX @@ -15,11 +15,11 @@ Following translations are available on the WWW: ABI/ - info on kernel <-> userspace ABI and relative interface stability. -BUG-HUNTING +admin-guide/bug-hunting.rst - brute force method of doing binary search of patches to find bug. -Changes +process/changes.rst - list of changes that break older software packages. -CodingStyle +process/coding-style.rst - how the maintainers expect the C code in the kernel to look. DMA-API.txt - DMA API, pci_ API & extensions for non-consistent memory machines. @@ -33,7 +33,7 @@ DocBook/ - directory with DocBook templates etc. for kernel documentation. EDID/ - directory with info on customizing EDID for broken gfx/displays. -HOWTO +process/howto.rst - the process and procedures of how to do Linux kernel development. IPMI.txt - info on Linux Intelligent Platform Management Interface (IPMI) Driver. @@ -48,7 +48,7 @@ Intel-IOMMU.txt Makefile - This file does nothing. Removing it breaks make htmldocs and make distclean. -ManagementStyle +process/management-style.rst - how to (attempt to) manage kernel hackers. RCU/ - directory with info on RCU (read-copy update). @@ -56,13 +56,13 @@ SAK.txt - info on Secure Attention Keys. SM501.txt - Silicon Motion SM501 multimedia companion chip -SecurityBugs +admin-guide/security-bugs.rst - procedure for reporting security bugs found in the kernel. -SubmitChecklist +process/submit-checklist.rst - Linux kernel patch submission checklist. -SubmittingDrivers +process/submitting-drivers.rst - procedure to get a new driver source included into the kernel tree. -SubmittingPatches +process/submitting-patches.rst - procedure to get a source patch included into the kernel tree. VGA-softcursor.txt - how to change your VGA cursor from a blinking underscore. @@ -72,7 +72,7 @@ acpi/ - info on ACPI-specific hooks in the kernel. aoe/ - description of AoE (ATA over Ethernet) along with config examples. -applying-patches.txt +process/applying-patches.rst - description of various trees and how to apply their patches. arm/ - directory with info about Linux on the ARM architecture. @@ -86,7 +86,7 @@ auxdisplay/ - misc. LCD driver documentation (cfag12864b, ks0108). backlight/ - directory with info on controlling backlights in flat panel displays -bad_memory.txt +admin-guide/bad-memory.rst - how to use kernel parameters to exclude bad RAM regions. basic_profiling.txt - basic instructions for those who wants to profile Linux kernel. @@ -150,11 +150,11 @@ debugging-via-ohci1394.txt - how to use firewire like a hardware debugger memory reader. dell_rbu.txt - document demonstrating the use of the Dell Remote BIOS Update driver. -development-process/ +process/ - how to work with the mainline kernel development process. device-mapper/ - directory with info on Device Mapper. -devices.txt +admin-guide/devices.rst - plain ASCII listing of all the nodes in /dev/ with major minor #'s. devicetree/ - directory with info on device tree files used by OF/PowerPC/ARM @@ -166,8 +166,6 @@ dontdiff - file containing a list of files that should never be diff'ed. driver-model/ - directory with info about Linux driver model. -dvb/ - - info on Linux Digital Video Broadcast (DVB) subsystem. dynamic-debug-howto.txt - how to use the dynamic debug (dyndbg) feature. early-userspace/ @@ -178,7 +176,7 @@ efi-stub.txt - How to use the EFI boot stub to bypass GRUB or elilo on EFI systems. eisa.txt - info on EISA bus support. -email-clients.txt +process/email-clients.rst - info on how to use e-mail to send un-mangled (git) patches. extcon/ - directory with porting guide for Android kernel switch driver. @@ -226,9 +224,9 @@ ia64/ - directory with info about Linux on Intel 64 bit architecture. infiniband/ - directory with documents concerning Linux InfiniBand support. -init.txt +admin-guide/init.rst - what to do when the kernel can't find the 1st process to run. -initrd.txt +admin-guide/initrd.rst - how to use the RAM disk as an initial/temporary root filesystem. input/ - info on Linux input device support. @@ -248,7 +246,7 @@ isapnp.txt - info on Linux ISA Plug & Play support. isdn/ - directory with info on the Linux ISDN support, and supported cards. -java.txt +admin-guide/java.rst - info on the in-kernel binary support for Java(tm). ja_JP/ - directory with Japanese translations of various documents @@ -256,11 +254,11 @@ kbuild/ - directory with info about the kernel build process. kdump/ - directory with mini HowTo on getting the crash dump code to work. -kernel-docs.txt +process/kernel-docs.rst - listing of various WWW + books that document kernel internals. kernel-documentation.rst - how to write and format reStructuredText kernel documentation -kernel-parameters.txt +admin-guide/kernel-parameters.rst - summary listing of command line / boot prompt args for the kernel. kernel-per-CPU-kthreads.txt - List of all per-CPU kthreads and how they introduce jitter. @@ -302,7 +300,7 @@ magic-number.txt - list of magic numbers used to mark/protect kernel data structures. mailbox.txt - How to write drivers for the common mailbox framework (IPC). -md.txt +admin-guide/md.rst - info on boot arguments for the multiple devices driver. media-framework.txt - info on media framework, its data structures, functions and usage. @@ -326,7 +324,7 @@ module-signing.txt - Kernel module signing for increased security when loading modules. mtd/ - directory with info about memory technology devices (flash) -mono.txt +admin-guide/mono.rst - how to execute Mono-based .NET binaries with the help of BINFMT_MISC. namespaces/ - directory with various information about namespaces @@ -340,7 +338,7 @@ nommu-mmap.txt - documentation about no-mmu memory mapping support. numastat.txt - info on how to read Numa policy hit/miss statistics in sysfs. -oops-tracing.txt +admin-guide/oops-tracing.rst - how to decode those nasty internal kernel error dump messages. padata.txt - An introduction to the "padata" parallel execution API @@ -378,7 +376,7 @@ ptp/ - directory with info on support for IEEE 1588 PTP clocks in Linux. pwm.txt - info on the pulse width modulation driver subsystem -ramoops.txt +admin-guide/ramoops.rst - documentation of the ramoops oops/panic logging module. rapidio/ - directory with info on RapidIO packet-based fabric interconnect @@ -406,7 +404,7 @@ security/ - directory that contains security-related info serial/ - directory with info on the low level serial API. -serial-console.txt +admin-guide/serial-console.rst - how to set up Linux with a serial line console as the default. sgi-ioc4.txt - description of the SGI IOC4 PCI (multi function) device. @@ -420,9 +418,9 @@ sparse.txt - info on how to obtain and use the sparse tool for typechecking. spi/ - overview of Linux kernel Serial Peripheral Interface (SPI) support. -stable_api_nonsense.txt +process/stable-api-nonsense.rst - info on why the kernel does not have a stable in-kernel api or abi. -stable_kernel_rules.txt +process/stable-kernel-rules.rst - rules and procedures for the -stable kernel releases. static-keys.txt - info on how static keys allow debug code in hotpaths via patching @@ -444,7 +442,7 @@ trace/ - directory with info on tracing technologies within linux unaligned-memory-access.txt - info on how to avoid arch breaking unaligned memory access in code. -unicode.txt +admin-guide/unicode.rst - info on the Unicode character/font mapping used in Linux. unshare.txt - description of the Linux unshare system call. @@ -458,15 +456,13 @@ vgaarbiter.txt - info on enable/disable the legacy decoding on different VGA devices video-output.txt - sysfs class driver interface to enable/disable a video output device. -video4linux/ - - directory with info regarding video/TV/radio cards and linux. virtual/ - directory with information on the various linux virtualizations. vm/ - directory with info on the Linux vm code. vme_api.txt - file relating info on the VME bus API in linux -volatile-considered-harmful.txt +process/volatile-considered-harmful.rst - Why the "volatile" type class should not be used w1/ - directory with documents regarding the 1-wire (w1) subsystem. diff --git a/Documentation/ABI/README b/Documentation/ABI/README index 1fafc4b0..3121029 100644 --- a/Documentation/ABI/README +++ b/Documentation/ABI/README @@ -84,4 +84,4 @@ stable: - Kernel-internal symbols. Do not rely on the presence, absence, location, or type of any kernel symbol, either in System.map files or the kernel binary - itself. See Documentation/stable_api_nonsense.txt. + itself. See Documentation/process/stable-api-nonsense.rst. diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab index 91bd6ca..2cc0a72 100644 --- a/Documentation/ABI/testing/sysfs-kernel-slab +++ b/Documentation/ABI/testing/sysfs-kernel-slab @@ -347,7 +347,7 @@ Description: because of fragmentation, SLUB will retry with the minimum order possible depending on its characteristics. When debug_guardpage_minorder=N (N > 0) parameter is specified - (see Documentation/kernel-parameters.txt), the minimum possible + (see Documentation/admin-guide/kernel-parameters.rst), the minimum possible order is used and this sysfs entry can not be used to change the order at run time. diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index 9c61c03..320983c 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -1,1062 +1 @@ -.. _codingstyle: - -Linux kernel coding style -========================= - -This is a short document describing the preferred coding style for the -linux kernel. Coding style is very personal, and I won't **force** my -views on anybody, but this is what goes for anything that I have to be -able to maintain, and I'd prefer it for most other things too. Please -at least consider the points made here. - -First off, I'd suggest printing out a copy of the GNU coding standards, -and NOT read it. Burn them, it's a great symbolic gesture. - -Anyway, here goes: - - -1) Indentation --------------- - -Tabs are 8 characters, and thus indentations are also 8 characters. -There are heretic movements that try to make indentations 4 (or even 2!) -characters deep, and that is akin to trying to define the value of PI to -be 3. - -Rationale: The whole idea behind indentation is to clearly define where -a block of control starts and ends. Especially when you've been looking -at your screen for 20 straight hours, you'll find it a lot easier to see -how the indentation works if you have large indentations. - -Now, some people will claim that having 8-character indentations makes -the code move too far to the right, and makes it hard to read on a -80-character terminal screen. The answer to that is that if you need -more than 3 levels of indentation, you're screwed anyway, and should fix -your program. - -In short, 8-char indents make things easier to read, and have the added -benefit of warning you when you're nesting your functions too deep. -Heed that warning. - -The preferred way to ease multiple indentation levels in a switch statement is -to align the ``switch`` and its subordinate ``case`` labels in the same column -instead of ``double-indenting`` the ``case`` labels. E.g.: - -.. code-block:: c - - switch (suffix) { - case 'G': - case 'g': - mem <<= 30; - break; - case 'M': - case 'm': - mem <<= 20; - break; - case 'K': - case 'k': - mem <<= 10; - /* fall through */ - default: - break; - } - -Don't put multiple statements on a single line unless you have -something to hide: - -.. code-block:: c - - if (condition) do_this; - do_something_everytime; - -Don't put multiple assignments on a single line either. Kernel coding style -is super simple. Avoid tricky expressions. - -Outside of comments, documentation and except in Kconfig, spaces are never -used for indentation, and the above example is deliberately broken. - -Get a decent editor and don't leave whitespace at the end of lines. - - -2) Breaking long lines and strings ----------------------------------- - -Coding style is all about readability and maintainability using commonly -available tools. - -The limit on the length of lines is 80 columns and this is a strongly -preferred limit. - -Statements longer than 80 columns will be broken into sensible chunks, unless -exceeding 80 columns significantly increases readability and does not hide -information. Descendants are always substantially shorter than the parent and -are placed substantially to the right. The same applies to function headers -with a long argument list. However, never break user-visible strings such as -printk messages, because that breaks the ability to grep for them. - - -3) Placing Braces and Spaces ----------------------------- - -The other issue that always comes up in C styling is the placement of -braces. Unlike the indent size, there are few technical reasons to -choose one placement strategy over the other, but the preferred way, as -shown to us by the prophets Kernighan and Ritchie, is to put the opening -brace last on the line, and put the closing brace first, thusly: - -.. code-block:: c - - if (x is true) { - we do y - } - -This applies to all non-function statement blocks (if, switch, for, -while, do). E.g.: - -.. code-block:: c - - switch (action) { - case KOBJ_ADD: - return "add"; - case KOBJ_REMOVE: - return "remove"; - case KOBJ_CHANGE: - return "change"; - default: - return NULL; - } - -However, there is one special case, namely functions: they have the -opening brace at the beginning of the next line, thus: - -.. code-block:: c - - int function(int x) - { - body of function - } - -Heretic people all over the world have claimed that this inconsistency -is ... well ... inconsistent, but all right-thinking people know that -(a) K&R are **right** and (b) K&R are right. Besides, functions are -special anyway (you can't nest them in C). - -Note that the closing brace is empty on a line of its own, **except** in -the cases where it is followed by a continuation of the same statement, -ie a ``while`` in a do-statement or an ``else`` in an if-statement, like -this: - -.. code-block:: c - - do { - body of do-loop - } while (condition); - -and - -.. code-block:: c - - if (x == y) { - .. - } else if (x > y) { - ... - } else { - .... - } - -Rationale: K&R. - -Also, note that this brace-placement also minimizes the number of empty -(or almost empty) lines, without any loss of readability. Thus, as the -supply of new-lines on your screen is not a renewable resource (think -25-line terminal screens here), you have more empty lines to put -comments on. - -Do not unnecessarily use braces where a single statement will do. - -.. code-block:: c - - if (condition) - action(); - -and - -.. code-block:: none - - if (condition) - do_this(); - else - do_that(); - -This does not apply if only one branch of a conditional statement is a single -statement; in the latter case use braces in both branches: - -.. code-block:: c - - if (condition) { - do_this(); - do_that(); - } else { - otherwise(); - } - -3.1) Spaces -*********** - -Linux kernel style for use of spaces depends (mostly) on -function-versus-keyword usage. Use a space after (most) keywords. The -notable exceptions are sizeof, typeof, alignof, and __attribute__, which look -somewhat like functions (and are usually used with parentheses in Linux, -although they are not required in the language, as in: ``sizeof info`` after -``struct fileinfo info;`` is declared). - -So use a space after these keywords:: - - if, switch, case, for, do, while - -but not with sizeof, typeof, alignof, or __attribute__. E.g., - -.. code-block:: c - - - s = sizeof(struct file); - -Do not add spaces around (inside) parenthesized expressions. This example is -**bad**: - -.. code-block:: c - - - s = sizeof( struct file ); - -When declaring pointer data or a function that returns a pointer type, the -preferred use of ``*`` is adjacent to the data name or function name and not -adjacent to the type name. Examples: - -.. code-block:: c - - - char *linux_banner; - unsigned long long memparse(char *ptr, char **retptr); - char *match_strdup(substring_t *s); - -Use one space around (on each side of) most binary and ternary operators, -such as any of these:: - - = + - < > * / % | & ^ <= >= == != ? : - -but no space after unary operators:: - - & * + - ~ ! sizeof typeof alignof __attribute__ defined - -no space before the postfix increment & decrement unary operators:: - - ++ -- - -no space after the prefix increment & decrement unary operators:: - - ++ -- - -and no space around the ``.`` and ``->`` structure member operators. - -Do not leave trailing whitespace at the ends of lines. Some editors with -``smart`` indentation will insert whitespace at the beginning of new lines as -appropriate, so you can start typing the next line of code right away. -However, some such editors do not remove the whitespace if you end up not -putting a line of code there, such as if you leave a blank line. As a result, -you end up with lines containing trailing whitespace. - -Git will warn you about patches that introduce trailing whitespace, and can -optionally strip the trailing whitespace for you; however, if applying a series -of patches, this may make later patches in the series fail by changing their -context lines. - - -4) Naming ---------- - -C is a Spartan language, and so should your naming be. Unlike Modula-2 -and Pascal programmers, C programmers do not use cute names like -ThisVariableIsATemporaryCounter. A C programmer would call that -variable ``tmp``, which is much easier to write, and not the least more -difficult to understand. - -HOWEVER, while mixed-case names are frowned upon, descriptive names for -global variables are a must. To call a global function ``foo`` is a -shooting offense. - -GLOBAL variables (to be used only if you **really** need them) need to -have descriptive names, as do global functions. If you have a function -that counts the number of active users, you should call that -``count_active_users()`` or similar, you should **not** call it ``cntusr()``. - -Encoding the type of a function into the name (so-called Hungarian -notation) is brain damaged - the compiler knows the types anyway and can -check those, and it only confuses the programmer. No wonder MicroSoft -makes buggy programs. - -LOCAL variable names should be short, and to the point. If you have -some random integer loop counter, it should probably be called ``i``. -Calling it ``loop_counter`` is non-productive, if there is no chance of it -being mis-understood. Similarly, ``tmp`` can be just about any type of -variable that is used to hold a temporary value. - -If you are afraid to mix up your local variable names, you have another -problem, which is called the function-growth-hormone-imbalance syndrome. -See chapter 6 (Functions). - - -5) Typedefs ------------ - -Please don't use things like ``vps_t``. -It's a **mistake** to use typedef for structures and pointers. When you see a - -.. code-block:: c - - - vps_t a; - -in the source, what does it mean? -In contrast, if it says - -.. code-block:: c - - struct virtual_container *a; - -you can actually tell what ``a`` is. - -Lots of people think that typedefs ``help readability``. Not so. They are -useful only for: - - (a) totally opaque objects (where the typedef is actively used to **hide** - what the object is). - - Example: ``pte_t`` etc. opaque objects that you can only access using - the proper accessor functions. - - .. note:: - - Opaqueness and ``accessor functions`` are not good in themselves. - The reason we have them for things like pte_t etc. is that there - really is absolutely **zero** portably accessible information there. - - (b) Clear integer types, where the abstraction **helps** avoid confusion - whether it is ``int`` or ``long``. - - u8/u16/u32 are perfectly fine typedefs, although they fit into - category (d) better than here. - - .. note:: - - Again - there needs to be a **reason** for this. If something is - ``unsigned long``, then there's no reason to do - - typedef unsigned long myflags_t; - - but if there is a clear reason for why it under certain circumstances - might be an ``unsigned int`` and under other configurations might be - ``unsigned long``, then by all means go ahead and use a typedef. - - (c) when you use sparse to literally create a **new** type for - type-checking. - - (d) New types which are identical to standard C99 types, in certain - exceptional circumstances. - - Although it would only take a short amount of time for the eyes and - brain to become accustomed to the standard types like ``uint32_t``, - some people object to their use anyway. - - Therefore, the Linux-specific ``u8/u16/u32/u64`` types and their - signed equivalents which are identical to standard types are - permitted -- although they are not mandatory in new code of your - own. - - When editing existing code which already uses one or the other set - of types, you should conform to the existing choices in that code. - - (e) Types safe for use in userspace. - - In certain structures which are visible to userspace, we cannot - require C99 types and cannot use the ``u32`` form above. Thus, we - use __u32 and similar types in all structures which are shared - with userspace. - -Maybe there are other cases too, but the rule should basically be to NEVER -EVER use a typedef unless you can clearly match one of those rules. - -In general, a pointer, or a struct that has elements that can reasonably -be directly accessed should **never** be a typedef. - - -6) Functions ------------- - -Functions should be short and sweet, and do just one thing. They should -fit on one or two screenfuls of text (the ISO/ANSI screen size is 80x24, -as we all know), and do one thing and do that well. - -The maximum length of a function is inversely proportional to the -complexity and indentation level of that function. So, if you have a -conceptually simple function that is just one long (but simple) -case-statement, where you have to do lots of small things for a lot of -different cases, it's OK to have a longer function. - -However, if you have a complex function, and you suspect that a -less-than-gifted first-year high-school student might not even -understand what the function is all about, you should adhere to the -maximum limits all the more closely. Use helper functions with -descriptive names (you can ask the compiler to in-line them if you think -it's performance-critical, and it will probably do a better job of it -than you would have done). - -Another measure of the function is the number of local variables. They -shouldn't exceed 5-10, or you're doing something wrong. Re-think the -function, and split it into smaller pieces. A human brain can -generally easily keep track of about 7 different things, anything more -and it gets confused. You know you're brilliant, but maybe you'd like -to understand what you did 2 weeks from now. - -In source files, separate functions with one blank line. If the function is -exported, the **EXPORT** macro for it should follow immediately after the -closing function brace line. E.g.: - -.. code-block:: c - - int system_is_up(void) - { - return system_state == SYSTEM_RUNNING; - } - EXPORT_SYMBOL(system_is_up); - -In function prototypes, include parameter names with their data types. -Although this is not required by the C language, it is preferred in Linux -because it is a simple way to add valuable information for the reader. - - -7) Centralized exiting of functions ------------------------------------ - -Albeit deprecated by some people, the equivalent of the goto statement is -used frequently by compilers in form of the unconditional jump instruction. - -The goto statement comes in handy when a function exits from multiple -locations and some common work such as cleanup has to be done. If there is no -cleanup needed then just return directly. - -Choose label names which say what the goto does or why the goto exists. An -example of a good name could be ``out_free_buffer:`` if the goto frees ``buffer``. -Avoid using GW-BASIC names like ``err1:`` and ``err2:``, as you would have to -renumber them if you ever add or remove exit paths, and they make correctness -difficult to verify anyway. - -The rationale for using gotos is: - -- unconditional statements are easier to understand and follow -- nesting is reduced -- errors by not updating individual exit points when making - modifications are prevented -- saves the compiler work to optimize redundant code away ;) - -.. code-block:: c - - int fun(int a) - { - int result = 0; - char *buffer; - - buffer = kmalloc(SIZE, GFP_KERNEL); - if (!buffer) - return -ENOMEM; - - if (condition1) { - while (loop1) { - ... - } - result = 1; - goto out_buffer; - } - ... - out_free_buffer: - kfree(buffer); - return result; - } - -A common type of bug to be aware of is ``one err bugs`` which look like this: - -.. code-block:: c - - err: - kfree(foo->bar); - kfree(foo); - return ret; - -The bug in this code is that on some exit paths ``foo`` is NULL. Normally the -fix for this is to split it up into two error labels ``err_free_bar:`` and -``err_free_foo:``: - -.. code-block:: c - - err_free_bar: - kfree(foo->bar); - err_free_foo: - kfree(foo); - return ret; - -Ideally you should simulate errors to test all exit paths. - - -8) Commenting -------------- - -Comments are good, but there is also a danger of over-commenting. NEVER -try to explain HOW your code works in a comment: it's much better to -write the code so that the **working** is obvious, and it's a waste of -time to explain badly written code. - -Generally, you want your comments to tell WHAT your code does, not HOW. -Also, try to avoid putting comments inside a function body: if the -function is so complex that you need to separately comment parts of it, -you should probably go back to chapter 6 for a while. You can make -small comments to note or warn about something particularly clever (or -ugly), but try to avoid excess. Instead, put the comments at the head -of the function, telling people what it does, and possibly WHY it does -it. - -When commenting the kernel API functions, please use the kernel-doc format. -See the files Documentation/kernel-documentation.rst and scripts/kernel-doc -for details. - -The preferred style for long (multi-line) comments is: - -.. code-block:: c - - /* - * This is the preferred style for multi-line - * comments in the Linux kernel source code. - * Please use it consistently. - * - * Description: A column of asterisks on the left side, - * with beginning and ending almost-blank lines. - */ - -For files in net/ and drivers/net/ the preferred style for long (multi-line) -comments is a little different. - -.. code-block:: c - - /* The preferred comment style for files in net/ and drivers/net - * looks like this. - * - * It is nearly the same as the generally preferred comment style, - * but there is no initial almost-blank line. - */ - -It's also important to comment data, whether they are basic types or derived -types. To this end, use just one data declaration per line (no commas for -multiple data declarations). This leaves you room for a small comment on each -item, explaining its use. - - -9) You've made a mess of it ---------------------------- - -That's OK, we all do. You've probably been told by your long-time Unix -user helper that ``GNU emacs`` automatically formats the C sources for -you, and you've noticed that yes, it does do that, but the defaults it -uses are less than desirable (in fact, they are worse than random -typing - an infinite number of monkeys typing into GNU emacs would never -make a good program). - -So, you can either get rid of GNU emacs, or change it to use saner -values. To do the latter, you can stick the following in your .emacs file: - -.. code-block:: none - - (defun c-lineup-arglist-tabs-only (ignored) - "Line up argument lists by tabs, not spaces" - (let* ((anchor (c-langelem-pos c-syntactic-element)) - (column (c-langelem-2nd-pos c-syntactic-element)) - (offset (- (1+ column) anchor)) - (steps (floor offset c-basic-offset))) - (* (max steps 1) - c-basic-offset))) - - (add-hook 'c-mode-common-hook - (lambda () - ;; Add kernel style - (c-add-style - "linux-tabs-only" - '("linux" (c-offsets-alist - (arglist-cont-nonempty - c-lineup-gcc-asm-reg - c-lineup-arglist-tabs-only)))))) - - (add-hook 'c-mode-hook - (lambda () - (let ((filename (buffer-file-name))) - ;; Enable kernel mode for the appropriate files - (when (and filename - (string-match (expand-file-name "~/src/linux-trees") - filename)) - (setq indent-tabs-mode t) - (setq show-trailing-whitespace t) - (c-set-style "linux-tabs-only"))))) - -This will make emacs go better with the kernel coding style for C -files below ``~/src/linux-trees``. - -But even if you fail in getting emacs to do sane formatting, not -everything is lost: use ``indent``. - -Now, again, GNU indent has the same brain-dead settings that GNU emacs -has, which is why you need to give it a few command line options. -However, that's not too bad, because even the makers of GNU indent -recognize the authority of K&R (the GNU people aren't evil, they are -just severely misguided in this matter), so you just give indent the -options ``-kr -i8`` (stands for ``K&R, 8 character indents``), or use -``scripts/Lindent``, which indents in the latest style. - -``indent`` has a lot of options, and especially when it comes to comment -re-formatting you may want to take a look at the man page. But -remember: ``indent`` is not a fix for bad programming. - - -10) Kconfig configuration files -------------------------------- - -For all of the Kconfig* configuration files throughout the source tree, -the indentation is somewhat different. Lines under a ``config`` definition -are indented with one tab, while help text is indented an additional two -spaces. Example:: - - config AUDIT - bool "Auditing support" - depends on NET - help - Enable auditing infrastructure that can be used with another - kernel subsystem, such as SELinux (which requires this for - logging of avc messages output). Does not do system-call - auditing without CONFIG_AUDITSYSCALL. - -Seriously dangerous features (such as write support for certain -filesystems) should advertise this prominently in their prompt string:: - - config ADFS_FS_RW - bool "ADFS write support (DANGEROUS)" - depends on ADFS_FS - ... - -For full documentation on the configuration files, see the file -Documentation/kbuild/kconfig-language.txt. - - -11) Data structures -------------------- - -Data structures that have visibility outside the single-threaded -environment they are created and destroyed in should always have -reference counts. In the kernel, garbage collection doesn't exist (and -outside the kernel garbage collection is slow and inefficient), which -means that you absolutely **have** to reference count all your uses. - -Reference counting means that you can avoid locking, and allows multiple -users to have access to the data structure in parallel - and not having -to worry about the structure suddenly going away from under them just -because they slept or did something else for a while. - -Note that locking is **not** a replacement for reference counting. -Locking is used to keep data structures coherent, while reference -counting is a memory management technique. Usually both are needed, and -they are not to be confused with each other. - -Many data structures can indeed have two levels of reference counting, -when there are users of different ``classes``. The subclass count counts -the number of subclass users, and decrements the global count just once -when the subclass count goes to zero. - -Examples of this kind of ``multi-level-reference-counting`` can be found in -memory management (``struct mm_struct``: mm_users and mm_count), and in -filesystem code (``struct super_block``: s_count and s_active). - -Remember: if another thread can find your data structure, and you don't -have a reference count on it, you almost certainly have a bug. - - -12) Macros, Enums and RTL -------------------------- - -Names of macros defining constants and labels in enums are capitalized. - -.. code-block:: c - - #define CONSTANT 0x12345 - -Enums are preferred when defining several related constants. - -CAPITALIZED macro names are appreciated but macros resembling functions -may be named in lower case. - -Generally, inline functions are preferable to macros resembling functions. - -Macros with multiple statements should be enclosed in a do - while block: - -.. code-block:: c - - #define macrofun(a, b, c) \ - do { \ - if (a == 5) \ - do_this(b, c); \ - } while (0) - -Things to avoid when using macros: - -1) macros that affect control flow: - -.. code-block:: c - - #define FOO(x) \ - do { \ - if (blah(x) < 0) \ - return -EBUGGERED; \ - } while (0) - -is a **very** bad idea. It looks like a function call but exits the ``calling`` -function; don't break the internal parsers of those who will read the code. - -2) macros that depend on having a local variable with a magic name: - -.. code-block:: c - - #define FOO(val) bar(index, val) - -might look like a good thing, but it's confusing as hell when one reads the -code and it's prone to breakage from seemingly innocent changes. - -3) macros with arguments that are used as l-values: FOO(x) = y; will -bite you if somebody e.g. turns FOO into an inline function. - -4) forgetting about precedence: macros defining constants using expressions -must enclose the expression in parentheses. Beware of similar issues with -macros using parameters. - -.. code-block:: c - - #define CONSTANT 0x4000 - #define CONSTEXP (CONSTANT | 3) - -5) namespace collisions when defining local variables in macros resembling -functions: - -.. code-block:: c - - #define FOO(x) \ - ({ \ - typeof(x) ret; \ - ret = calc_ret(x); \ - (ret); \ - }) - -ret is a common name for a local variable - __foo_ret is less likely -to collide with an existing variable. - -The cpp manual deals with macros exhaustively. The gcc internals manual also -covers RTL which is used frequently with assembly language in the kernel. - - -13) Printing kernel messages ----------------------------- - -Kernel developers like to be seen as literate. Do mind the spelling -of kernel messages to make a good impression. Do not use crippled -words like ``dont``; use ``do not`` or ``don't`` instead. Make the messages -concise, clear, and unambiguous. - -Kernel messages do not have to be terminated with a period. - -Printing numbers in parentheses (%d) adds no value and should be avoided. - -There are a number of driver model diagnostic macros in <linux/device.h> -which you should use to make sure messages are matched to the right device -and driver, and are tagged with the right level: dev_err(), dev_warn(), -dev_info(), and so forth. For messages that aren't associated with a -particular device, <linux/printk.h> defines pr_notice(), pr_info(), -pr_warn(), pr_err(), etc. - -Coming up with good debugging messages can be quite a challenge; and once -you have them, they can be a huge help for remote troubleshooting. However -debug message printing is handled differently than printing other non-debug -messages. While the other pr_XXX() functions print unconditionally, -pr_debug() does not; it is compiled out by default, unless either DEBUG is -defined or CONFIG_DYNAMIC_DEBUG is set. That is true for dev_dbg() also, -and a related convention uses VERBOSE_DEBUG to add dev_vdbg() messages to -the ones already enabled by DEBUG. - -Many subsystems have Kconfig debug options to turn on -DDEBUG in the -corresponding Makefile; in other cases specific files #define DEBUG. And -when a debug message should be unconditionally printed, such as if it is -already inside a debug-related #ifdef section, printk(KERN_DEBUG ...) can be -used. - - -14) Allocating memory ---------------------- - -The kernel provides the following general purpose memory allocators: -kmalloc(), kzalloc(), kmalloc_array(), kcalloc(), vmalloc(), and -vzalloc(). Please refer to the API documentation for further information -about them. - -The preferred form for passing a size of a struct is the following: - -.. code-block:: c - - p = kmalloc(sizeof(*p), ...); - -The alternative form where struct name is spelled out hurts readability and -introduces an opportunity for a bug when the pointer variable type is changed -but the corresponding sizeof that is passed to a memory allocator is not. - -Casting the return value which is a void pointer is redundant. The conversion -from void pointer to any other pointer type is guaranteed by the C programming -language. - -The preferred form for allocating an array is the following: - -.. code-block:: c - - p = kmalloc_array(n, sizeof(...), ...); - -The preferred form for allocating a zeroed array is the following: - -.. code-block:: c - - p = kcalloc(n, sizeof(...), ...); - -Both forms check for overflow on the allocation size n * sizeof(...), -and return NULL if that occurred. - - -15) The inline disease ----------------------- - -There appears to be a common misperception that gcc has a magic "make me -faster" speedup option called ``inline``. While the use of inlines can be -appropriate (for example as a means of replacing macros, see Chapter 12), it -very often is not. Abundant use of the inline keyword leads to a much bigger -kernel, which in turn slows the system as a whole down, due to a bigger -icache footprint for the CPU and simply because there is less memory -available for the pagecache. Just think about it; a pagecache miss causes a -disk seek, which easily takes 5 milliseconds. There are a LOT of cpu cycles -that can go into these 5 milliseconds. - -A reasonable rule of thumb is to not put inline at functions that have more -than 3 lines of code in them. An exception to this rule are the cases where -a parameter is known to be a compiletime constant, and as a result of this -constantness you *know* the compiler will be able to optimize most of your -function away at compile time. For a good example of this later case, see -the kmalloc() inline function. - -Often people argue that adding inline to functions that are static and used -only once is always a win since there is no space tradeoff. While this is -technically correct, gcc is capable of inlining these automatically without -help, and the maintenance issue of removing the inline when a second user -appears outweighs the potential value of the hint that tells gcc to do -something it would have done anyway. - - -16) Function return values and names ------------------------------------- - -Functions can return values of many different kinds, and one of the -most common is a value indicating whether the function succeeded or -failed. Such a value can be represented as an error-code integer -(-Exxx = failure, 0 = success) or a ``succeeded`` boolean (0 = failure, -non-zero = success). - -Mixing up these two sorts of representations is a fertile source of -difficult-to-find bugs. If the C language included a strong distinction -between integers and booleans then the compiler would find these mistakes -for us... but it doesn't. To help prevent such bugs, always follow this -convention:: - - If the name of a function is an action or an imperative command, - the function should return an error-code integer. If the name - is a predicate, the function should return a "succeeded" boolean. - -For example, ``add work`` is a command, and the add_work() function returns 0 -for success or -EBUSY for failure. In the same way, ``PCI device present`` is -a predicate, and the pci_dev_present() function returns 1 if it succeeds in -finding a matching device or 0 if it doesn't. - -All EXPORTed functions must respect this convention, and so should all -public functions. Private (static) functions need not, but it is -recommended that they do. - -Functions whose return value is the actual result of a computation, rather -than an indication of whether the computation succeeded, are not subject to -this rule. Generally they indicate failure by returning some out-of-range -result. Typical examples would be functions that return pointers; they use -NULL or the ERR_PTR mechanism to report failure. - - -17) Don't re-invent the kernel macros -------------------------------------- - -The header file include/linux/kernel.h contains a number of macros that -you should use, rather than explicitly coding some variant of them yourself. -For example, if you need to calculate the length of an array, take advantage -of the macro - -.. code-block:: c - - #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) - -Similarly, if you need to calculate the size of some structure member, use - -.. code-block:: c - - #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) - -There are also min() and max() macros that do strict type checking if you -need them. Feel free to peruse that header file to see what else is already -defined that you shouldn't reproduce in your code. - - -18) Editor modelines and other cruft ------------------------------------- - -Some editors can interpret configuration information embedded in source files, -indicated with special markers. For example, emacs interprets lines marked -like this: - -.. code-block:: c - - -*- mode: c -*- - -Or like this: - -.. code-block:: c - - /* - Local Variables: - compile-command: "gcc -DMAGIC_DEBUG_FLAG foo.c" - End: - */ - -Vim interprets markers that look like this: - -.. code-block:: c - - /* vim:set sw=8 noet */ - -Do not include any of these in source files. People have their own personal -editor configurations, and your source files should not override them. This -includes markers for indentation and mode configuration. People may use their -own custom mode, or may have some other magic method for making indentation -work correctly. - - -19) Inline assembly -------------------- - -In architecture-specific code, you may need to use inline assembly to interface -with CPU or platform functionality. Don't hesitate to do so when necessary. -However, don't use inline assembly gratuitously when C can do the job. You can -and should poke hardware from C when possible. - -Consider writing simple helper functions that wrap common bits of inline -assembly, rather than repeatedly writing them with slight variations. Remember -that inline assembly can use C parameters. - -Large, non-trivial assembly functions should go in .S files, with corresponding -C prototypes defined in C header files. The C prototypes for assembly -functions should use ``asmlinkage``. - -You may need to mark your asm statement as volatile, to prevent GCC from -removing it if GCC doesn't notice any side effects. You don't always need to -do so, though, and doing so unnecessarily can limit optimization. - -When writing a single inline assembly statement containing multiple -instructions, put each instruction on a separate line in a separate quoted -string, and end each string except the last with \n\t to properly indent the -next instruction in the assembly output: - -.. code-block:: c - - asm ("magic %reg1, #42\n\t" - "more_magic %reg2, %reg3" - : /* outputs */ : /* inputs */ : /* clobbers */); - - -20) Conditional Compilation ---------------------------- - -Wherever possible, don't use preprocessor conditionals (#if, #ifdef) in .c -files; doing so makes code harder to read and logic harder to follow. Instead, -use such conditionals in a header file defining functions for use in those .c -files, providing no-op stub versions in the #else case, and then call those -functions unconditionally from .c files. The compiler will avoid generating -any code for the stub calls, producing identical results, but the logic will -remain easy to follow. - -Prefer to compile out entire functions, rather than portions of functions or -portions of expressions. Rather than putting an ifdef in an expression, factor -out part or all of the expression into a separate helper function and apply the -conditional to that function. - -If you have a function or variable which may potentially go unused in a -particular configuration, and the compiler would warn about its definition -going unused, mark the definition as __maybe_unused rather than wrapping it in -a preprocessor conditional. (However, if a function or variable *always* goes -unused, delete it.) - -Within code, where possible, use the IS_ENABLED macro to convert a Kconfig -symbol into a C boolean expression, and use it in a normal C conditional: - -.. code-block:: c - - if (IS_ENABLED(CONFIG_SOMETHING)) { - ... - } - -The compiler will constant-fold the conditional away, and include or exclude -the block of code just as with an #ifdef, so this will not add any runtime -overhead. However, this approach still allows the C compiler to see the code -inside the block, and check it for correctness (syntax, types, symbol -references, etc). Thus, you still have to use an #ifdef if the code inside the -block references symbols that will not exist if the condition is not met. - -At the end of any non-trivial #if or #ifdef block (more than a few lines), -place a comment after the #endif on the same line, noting the conditional -expression used. For instance: - -.. code-block:: c - - #ifdef CONFIG_SOMETHING - ... - #endif /* CONFIG_SOMETHING */ - - -Appendix I) References ----------------------- - -The C Programming Language, Second Edition -by Brian W. Kernighan and Dennis M. Ritchie. -Prentice Hall, Inc., 1988. -ISBN 0-13-110362-8 (paperback), 0-13-110370-9 (hardback). - -The Practice of Programming -by Brian W. Kernighan and Rob Pike. -Addison-Wesley, Inc., 1999. -ISBN 0-201-61586-X. - -GNU manuals - where in compliance with K&R and this text - for cpp, gcc, -gcc internals and indent, all available from http://www.gnu.org/manual/ - -WG14 is the international standardization working group for the programming -language C, URL: http://www.open-std.org/JTC1/SC22/WG14/ - -Kernel CodingStyle, by greg@kroah.com at OLS 2002: -http://www.kroah.com/linux/talks/ols_2002_kernel_codingstyle_talk/html/ +This file has moved to process/coding-style.rst diff --git a/Documentation/DocBook/kernel-hacking.tmpl b/Documentation/DocBook/kernel-hacking.tmpl index 2a27227..da5c087 100644 --- a/Documentation/DocBook/kernel-hacking.tmpl +++ b/Documentation/DocBook/kernel-hacking.tmpl @@ -1208,8 +1208,8 @@ static struct block_device_operations opt_fops = { <listitem> <para> - Finally, don't forget to read <filename>Documentation/SubmittingPatches</filename> - and possibly <filename>Documentation/SubmittingDrivers</filename>. + Finally, don't forget to read <filename>Documentation/process/submitting-patches.rst</filename> + and possibly <filename>Documentation/process/submitting-drivers.rst</filename>. </para> </listitem> </itemizedlist> diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches index 36f1ded..8145570 100644 --- a/Documentation/SubmittingPatches +++ b/Documentation/SubmittingPatches @@ -1,841 +1 @@ -.. _submittingpatches: - -How to Get Your Change Into the Linux Kernel or Care And Operation Of Your Linus Torvalds -========================================================================================= - -For a person or company who wishes to submit a change to the Linux -kernel, the process can sometimes be daunting if you're not familiar -with "the system." This text is a collection of suggestions which -can greatly increase the chances of your change being accepted. - -This document contains a large number of suggestions in a relatively terse -format. For detailed information on how the kernel development process -works, see :ref:`Documentation/development-process <development_process_main>`. -Also, read :ref:`Documentation/SubmitChecklist <submitchecklist>` -for a list of items to check before -submitting code. If you are submitting a driver, also read -:ref:`Documentation/SubmittingDrivers <submittingdrivers>`; -for device tree binding patches, read -Documentation/devicetree/bindings/submitting-patches.txt. - -Many of these steps describe the default behavior of the ``git`` version -control system; if you use ``git`` to prepare your patches, you'll find much -of the mechanical work done for you, though you'll still need to prepare -and document a sensible set of patches. In general, use of ``git`` will make -your life as a kernel developer easier. - -Creating and Sending your Change -******************************** - - -0) Obtain a current source tree -------------------------------- - -If you do not have a repository with the current kernel source handy, use -``git`` to obtain one. You'll want to start with the mainline repository, -which can be grabbed with:: - - git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git - -Note, however, that you may not want to develop against the mainline tree -directly. Most subsystem maintainers run their own trees and want to see -patches prepared against those trees. See the **T:** entry for the subsystem -in the MAINTAINERS file to find that tree, or simply ask the maintainer if -the tree is not listed there. - -It is still possible to download kernel releases via tarballs (as described -in the next section), but that is the hard way to do kernel development. - -1) ``diff -up`` ---------------- - -If you must generate your patches by hand, use ``diff -up`` or ``diff -uprN`` -to create patches. Git generates patches in this form by default; if -you're using ``git``, you can skip this section entirely. - -All changes to the Linux kernel occur in the form of patches, as -generated by :manpage:`diff(1)`. When creating your patch, make sure to -create it in "unified diff" format, as supplied by the ``-u`` argument -to :manpage:`diff(1)`. -Also, please use the ``-p`` argument which shows which C function each -change is in - that makes the resultant ``diff`` a lot easier to read. -Patches should be based in the root kernel source directory, -not in any lower subdirectory. - -To create a patch for a single file, it is often sufficient to do:: - - SRCTREE= linux - MYFILE= drivers/net/mydriver.c - - cd $SRCTREE - cp $MYFILE $MYFILE.orig - vi $MYFILE # make your change - cd .. - diff -up $SRCTREE/$MYFILE{.orig,} > /tmp/patch - -To create a patch for multiple files, you should unpack a "vanilla", -or unmodified kernel source tree, and generate a ``diff`` against your -own source tree. For example:: - - MYSRC= /devel/linux - - tar xvfz linux-3.19.tar.gz - mv linux-3.19 linux-3.19-vanilla - diff -uprN -X linux-3.19-vanilla/Documentation/dontdiff \ - linux-3.19-vanilla $MYSRC > /tmp/patch - -``dontdiff`` is a list of files which are generated by the kernel during -the build process, and should be ignored in any :manpage:`diff(1)`-generated -patch. - -Make sure your patch does not include any extra files which do not -belong in a patch submission. Make sure to review your patch -after- -generating it with :manpage:`diff(1)`, to ensure accuracy. - -If your changes produce a lot of deltas, you need to split them into -individual patches which modify things in logical stages; see -:ref:`split_changes`. This will facilitate review by other kernel developers, -very important if you want your patch accepted. - -If you're using ``git``, ``git rebase -i`` can help you with this process. If -you're not using ``git``, ``quilt`` <http://savannah.nongnu.org/projects/quilt> -is another popular alternative. - -.. _describe_changes: - -2) Describe your changes ------------------------- - -Describe your problem. Whether your patch is a one-line bug fix or -5000 lines of a new feature, there must be an underlying problem that -motivated you to do this work. Convince the reviewer that there is a -problem worth fixing and that it makes sense for them to read past the -first paragraph. - -Describe user-visible impact. Straight up crashes and lockups are -pretty convincing, but not all bugs are that blatant. Even if the -problem was spotted during code review, describe the impact you think -it can have on users. Keep in mind that the majority of Linux -installations run kernels from secondary stable trees or -vendor/product-specific trees that cherry-pick only specific patches -from upstream, so include anything that could help route your change -downstream: provoking circumstances, excerpts from dmesg, crash -descriptions, performance regressions, latency spikes, lockups, etc. - -Quantify optimizations and trade-offs. If you claim improvements in -performance, memory consumption, stack footprint, or binary size, -include numbers that back them up. But also describe non-obvious -costs. Optimizations usually aren't free but trade-offs between CPU, -memory, and readability; or, when it comes to heuristics, between -different workloads. Describe the expected downsides of your -optimization so that the reviewer can weigh costs against benefits. - -Once the problem is established, describe what you are actually doing -about it in technical detail. It's important to describe the change -in plain English for the reviewer to verify that the code is behaving -as you intend it to. - -The maintainer will thank you if you write your patch description in a -form which can be easily pulled into Linux's source code management -system, ``git``, as a "commit log". See :ref:`explicit_in_reply_to`. - -Solve only one problem per patch. If your description starts to get -long, that's a sign that you probably need to split up your patch. -See :ref:`split_changes`. - -When you submit or resubmit a patch or patch series, include the -complete patch description and justification for it. Don't just -say that this is version N of the patch (series). Don't expect the -subsystem maintainer to refer back to earlier patch versions or referenced -URLs to find the patch description and put that into the patch. -I.e., the patch (series) and its description should be self-contained. -This benefits both the maintainers and reviewers. Some reviewers -probably didn't even receive earlier versions of the patch. - -Describe your changes in imperative mood, e.g. "make xyzzy do frotz" -instead of "[This patch] makes xyzzy do frotz" or "[I] changed xyzzy -to do frotz", as if you are giving orders to the codebase to change -its behaviour. - -If the patch fixes a logged bug entry, refer to that bug entry by -number and URL. If the patch follows from a mailing list discussion, -give a URL to the mailing list archive; use the https://lkml.kernel.org/ -redirector with a ``Message-Id``, to ensure that the links cannot become -stale. - -However, try to make your explanation understandable without external -resources. In addition to giving a URL to a mailing list archive or -bug, summarize the relevant points of the discussion that led to the -patch as submitted. - -If you want to refer to a specific commit, don't just refer to the -SHA-1 ID of the commit. Please also include the oneline summary of -the commit, to make it easier for reviewers to know what it is about. -Example:: - - Commit e21d2170f36602ae2708 ("video: remove unnecessary - platform_set_drvdata()") removed the unnecessary - platform_set_drvdata(), but left the variable "dev" unused, - delete it. - -You should also be sure to use at least the first twelve characters of the -SHA-1 ID. The kernel repository holds a *lot* of objects, making -collisions with shorter IDs a real possibility. Bear in mind that, even if -there is no collision with your six-character ID now, that condition may -change five years from now. - -If your patch fixes a bug in a specific commit, e.g. you found an issue using -``git bisect``, please use the 'Fixes:' tag with the first 12 characters of -the SHA-1 ID, and the one line summary. For example:: - - Fixes: e21d2170f366 ("video: remove unnecessary platform_set_drvdata()") - -The following ``git config`` settings can be used to add a pretty format for -outputting the above style in the ``git log`` or ``git show`` commands:: - - [core] - abbrev = 12 - [pretty] - fixes = Fixes: %h (\"%s\") - -.. _split_changes: - -3) Separate your changes ------------------------- - -Separate each **logical change** into a separate patch. - -For example, if your changes include both bug fixes and performance -enhancements for a single driver, separate those changes into two -or more patches. If your changes include an API update, and a new -driver which uses that new API, separate those into two patches. - -On the other hand, if you make a single change to numerous files, -group those changes into a single patch. Thus a single logical change -is contained within a single patch. - -The point to remember is that each patch should make an easily understood -change that can be verified by reviewers. Each patch should be justifiable -on its own merits. - -If one patch depends on another patch in order for a change to be -complete, that is OK. Simply note **"this patch depends on patch X"** -in your patch description. - -When dividing your change into a series of patches, take special care to -ensure that the kernel builds and runs properly after each patch in the -series. Developers using ``git bisect`` to track down a problem can end up -splitting your patch series at any point; they will not thank you if you -introduce bugs in the middle. - -If you cannot condense your patch set into a smaller set of patches, -then only post say 15 or so at a time and wait for review and integration. - - - -4) Style-check your changes ---------------------------- - -Check your patch for basic style violations, details of which can be -found in -:ref:`Documentation/CodingStyle <codingstyle>`. -Failure to do so simply wastes -the reviewers time and will get your patch rejected, probably -without even being read. - -One significant exception is when moving code from one file to -another -- in this case you should not modify the moved code at all in -the same patch which moves it. This clearly delineates the act of -moving the code and your changes. This greatly aids review of the -actual differences and allows tools to better track the history of -the code itself. - -Check your patches with the patch style checker prior to submission -(scripts/checkpatch.pl). Note, though, that the style checker should be -viewed as a guide, not as a replacement for human judgment. If your code -looks better with a violation then its probably best left alone. - -The checker reports at three levels: - - ERROR: things that are very likely to be wrong - - WARNING: things requiring careful review - - CHECK: things requiring thought - -You should be able to justify all violations that remain in your -patch. - - -5) Select the recipients for your patch ---------------------------------------- - -You should always copy the appropriate subsystem maintainer(s) on any patch -to code that they maintain; look through the MAINTAINERS file and the -source code revision history to see who those maintainers are. The -script scripts/get_maintainer.pl can be very useful at this step. If you -cannot find a maintainer for the subsystem you are working on, Andrew -Morton (akpm@linux-foundation.org) serves as a maintainer of last resort. - -You should also normally choose at least one mailing list to receive a copy -of your patch set. linux-kernel@vger.kernel.org functions as a list of -last resort, but the volume on that list has caused a number of developers -to tune it out. Look in the MAINTAINERS file for a subsystem-specific -list; your patch will probably get more attention there. Please do not -spam unrelated lists, though. - -Many kernel-related lists are hosted on vger.kernel.org; you can find a -list of them at http://vger.kernel.org/vger-lists.html. There are -kernel-related lists hosted elsewhere as well, though. - -Do not send more than 15 patches at once to the vger mailing lists!!! - -Linus Torvalds is the final arbiter of all changes accepted into the -Linux kernel. His e-mail address is <torvalds@linux-foundation.org>. -He gets a lot of e-mail, and, at this point, very few patches go through -Linus directly, so typically you should do your best to -avoid- -sending him e-mail. - -If you have a patch that fixes an exploitable security bug, send that patch -to security@kernel.org. For severe bugs, a short embargo may be considered -to allow distributors to get the patch out to users; in such cases, -obviously, the patch should not be sent to any public lists. - -Patches that fix a severe bug in a released kernel should be directed -toward the stable maintainers by putting a line like this:: - - Cc: stable@vger.kernel.org - -into the sign-off area of your patch (note, NOT an email recipient). You -should also read -:ref:`Documentation/stable_kernel_rules.txt <stable_kernel_rules>` -in addition to this file. - -Note, however, that some subsystem maintainers want to come to their own -conclusions on which patches should go to the stable trees. The networking -maintainer, in particular, would rather not see individual developers -adding lines like the above to their patches. - -If changes affect userland-kernel interfaces, please send the MAN-PAGES -maintainer (as listed in the MAINTAINERS file) a man-pages patch, or at -least a notification of the change, so that some information makes its way -into the manual pages. User-space API changes should also be copied to -linux-api@vger.kernel.org. - -For small patches you may want to CC the Trivial Patch Monkey -trivial@kernel.org which collects "trivial" patches. Have a look -into the MAINTAINERS file for its current manager. - -Trivial patches must qualify for one of the following rules: - -- Spelling fixes in documentation -- Spelling fixes for errors which could break :manpage:`grep(1)` -- Warning fixes (cluttering with useless warnings is bad) -- Compilation fixes (only if they are actually correct) -- Runtime fixes (only if they actually fix things) -- Removing use of deprecated functions/macros -- Contact detail and documentation fixes -- Non-portable code replaced by portable code (even in arch-specific, - since people copy, as long as it's trivial) -- Any fix by the author/maintainer of the file (ie. patch monkey - in re-transmission mode) - - - -6) No MIME, no links, no compression, no attachments. Just plain text ----------------------------------------------------------------------- - -Linus and other kernel developers need to be able to read and comment -on the changes you are submitting. It is important for a kernel -developer to be able to "quote" your changes, using standard e-mail -tools, so that they may comment on specific portions of your code. - -For this reason, all patches should be submitted by e-mail "inline". - -.. warning:: - - Be wary of your editor's word-wrap corrupting your patch, - if you choose to cut-n-paste your patch. - -Do not attach the patch as a MIME attachment, compressed or not. -Many popular e-mail applications will not always transmit a MIME -attachment as plain text, making it impossible to comment on your -code. A MIME attachment also takes Linus a bit more time to process, -decreasing the likelihood of your MIME-attached change being accepted. - -Exception: If your mailer is mangling patches then someone may ask -you to re-send them using MIME. - -See :ref:`Documentation/email-clients.txt <email_clients>` -for hints about configuring your e-mail client so that it sends your patches -untouched. - -7) E-mail size --------------- - -Large changes are not appropriate for mailing lists, and some -maintainers. If your patch, uncompressed, exceeds 300 kB in size, -it is preferred that you store your patch on an Internet-accessible -server, and provide instead a URL (link) pointing to your patch. But note -that if your patch exceeds 300 kB, it almost certainly needs to be broken up -anyway. - -8) Respond to review comments ------------------------------ - -Your patch will almost certainly get comments from reviewers on ways in -which the patch can be improved. You must respond to those comments; -ignoring reviewers is a good way to get ignored in return. Review comments -or questions that do not lead to a code change should almost certainly -bring about a comment or changelog entry so that the next reviewer better -understands what is going on. - -Be sure to tell the reviewers what changes you are making and to thank them -for their time. Code review is a tiring and time-consuming process, and -reviewers sometimes get grumpy. Even in that case, though, respond -politely and address the problems they have pointed out. - - -9) Don't get discouraged - or impatient ---------------------------------------- - -After you have submitted your change, be patient and wait. Reviewers are -busy people and may not get to your patch right away. - -Once upon a time, patches used to disappear into the void without comment, -but the development process works more smoothly than that now. You should -receive comments within a week or so; if that does not happen, make sure -that you have sent your patches to the right place. Wait for a minimum of -one week before resubmitting or pinging reviewers - possibly longer during -busy times like merge windows. - - -10) Include PATCH in the subject --------------------------------- - -Due to high e-mail traffic to Linus, and to linux-kernel, it is common -convention to prefix your subject line with [PATCH]. This lets Linus -and other kernel developers more easily distinguish patches from other -e-mail discussions. - - - -11) Sign your work ------------------- - -To improve tracking of who did what, especially with patches that can -percolate to their final resting place in the kernel through several -layers of maintainers, we've introduced a "sign-off" procedure on -patches that are being emailed around. - -The sign-off is a simple line at the end of the explanation for the -patch, which certifies that you wrote it or otherwise have the right to -pass it on as an open-source patch. The rules are pretty simple: if you -can certify the below: - -Developer's Certificate of Origin 1.1 -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - -By making a contribution to this project, I certify that: - - (a) The contribution was created in whole or in part by me and I - have the right to submit it under the open source license - indicated in the file; or - - (b) The contribution is based upon previous work that, to the best - of my knowledge, is covered under an appropriate open source - license and I have the right under that license to submit that - work with modifications, whether created in whole or in part - by me, under the same open source license (unless I am - permitted to submit under a different license), as indicated - in the file; or - - (c) The contribution was provided directly to me by some other - person who certified (a), (b) or (c) and I have not modified - it. - - (d) I understand and agree that this project and the contribution - are public and that a record of the contribution (including all - personal information I submit with it, including my sign-off) is - maintained indefinitely and may be redistributed consistent with - this project or the open source license(s) involved. - -then you just add a line saying:: - - Signed-off-by: Random J Developer <random@developer.example.org> - -using your real name (sorry, no pseudonyms or anonymous contributions.) - -Some people also put extra tags at the end. They'll just be ignored for -now, but you can do this to mark internal company procedures or just -point out some special detail about the sign-off. - -If you are a subsystem or branch maintainer, sometimes you need to slightly -modify patches you receive in order to merge them, because the code is not -exactly the same in your tree and the submitters'. If you stick strictly to -rule (c), you should ask the submitter to rediff, but this is a totally -counter-productive waste of time and energy. Rule (b) allows you to adjust -the code, but then it is very impolite to change one submitter's code and -make him endorse your bugs. To solve this problem, it is recommended that -you add a line between the last Signed-off-by header and yours, indicating -the nature of your changes. While there is nothing mandatory about this, it -seems like prepending the description with your mail and/or name, all -enclosed in square brackets, is noticeable enough to make it obvious that -you are responsible for last-minute changes. Example:: - - Signed-off-by: Random J Developer <random@developer.example.org> - [lucky@maintainer.example.org: struct foo moved from foo.c to foo.h] - Signed-off-by: Lucky K Maintainer <lucky@maintainer.example.org> - -This practice is particularly helpful if you maintain a stable branch and -want at the same time to credit the author, track changes, merge the fix, -and protect the submitter from complaints. Note that under no circumstances -can you change the author's identity (the From header), as it is the one -which appears in the changelog. - -Special note to back-porters: It seems to be a common and useful practice -to insert an indication of the origin of a patch at the top of the commit -message (just after the subject line) to facilitate tracking. For instance, -here's what we see in a 3.x-stable release:: - - Date: Tue Oct 7 07:26:38 2014 -0400 - - libata: Un-break ATA blacklist - - commit 1c40279960bcd7d52dbdf1d466b20d24b99176c8 upstream. - -And here's what might appear in an older kernel once a patch is backported:: - - Date: Tue May 13 22:12:27 2008 +0200 - - wireless, airo: waitbusy() won't delay - - [backport of 2.6 commit b7acbdfbd1f277c1eb23f344f899cfa4cd0bf36a] - -Whatever the format, this information provides a valuable help to people -tracking your trees, and to people trying to troubleshoot bugs in your -tree. - - -12) When to use Acked-by: and Cc: ---------------------------------- - -The Signed-off-by: tag indicates that the signer was involved in the -development of the patch, or that he/she was in the patch's delivery path. - -If a person was not directly involved in the preparation or handling of a -patch but wishes to signify and record their approval of it then they can -ask to have an Acked-by: line added to the patch's changelog. - -Acked-by: is often used by the maintainer of the affected code when that -maintainer neither contributed to nor forwarded the patch. - -Acked-by: is not as formal as Signed-off-by:. It is a record that the acker -has at least reviewed the patch and has indicated acceptance. Hence patch -mergers will sometimes manually convert an acker's "yep, looks good to me" -into an Acked-by: (but note that it is usually better to ask for an -explicit ack). - -Acked-by: does not necessarily indicate acknowledgement of the entire patch. -For example, if a patch affects multiple subsystems and has an Acked-by: from -one subsystem maintainer then this usually indicates acknowledgement of just -the part which affects that maintainer's code. Judgement should be used here. -When in doubt people should refer to the original discussion in the mailing -list archives. - -If a person has had the opportunity to comment on a patch, but has not -provided such comments, you may optionally add a ``Cc:`` tag to the patch. -This is the only tag which might be added without an explicit action by the -person it names - but it should indicate that this person was copied on the -patch. This tag documents that potentially interested parties -have been included in the discussion. - - -13) Using Reported-by:, Tested-by:, Reviewed-by:, Suggested-by: and Fixes: --------------------------------------------------------------------------- - -The Reported-by tag gives credit to people who find bugs and report them and it -hopefully inspires them to help us again in the future. Please note that if -the bug was reported in private, then ask for permission first before using the -Reported-by tag. - -A Tested-by: tag indicates that the patch has been successfully tested (in -some environment) by the person named. This tag informs maintainers that -some testing has been performed, provides a means to locate testers for -future patches, and ensures credit for the testers. - -Reviewed-by:, instead, indicates that the patch has been reviewed and found -acceptable according to the Reviewer's Statement: - -Reviewer's statement of oversight -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - -By offering my Reviewed-by: tag, I state that: - - (a) I have carried out a technical review of this patch to - evaluate its appropriateness and readiness for inclusion into - the mainline kernel. - - (b) Any problems, concerns, or questions relating to the patch - have been communicated back to the submitter. I am satisfied - with the submitter's response to my comments. - - (c) While there may be things that could be improved with this - submission, I believe that it is, at this time, (1) a - worthwhile modification to the kernel, and (2) free of known - issues which would argue against its inclusion. - - (d) While I have reviewed the patch and believe it to be sound, I - do not (unless explicitly stated elsewhere) make any - warranties or guarantees that it will achieve its stated - purpose or function properly in any given situation. - -A Reviewed-by tag is a statement of opinion that the patch is an -appropriate modification of the kernel without any remaining serious -technical issues. Any interested reviewer (who has done the work) can -offer a Reviewed-by tag for a patch. This tag serves to give credit to -reviewers and to inform maintainers of the degree of review which has been -done on the patch. Reviewed-by: tags, when supplied by reviewers known to -understand the subject area and to perform thorough reviews, will normally -increase the likelihood of your patch getting into the kernel. - -A Suggested-by: tag indicates that the patch idea is suggested by the person -named and ensures credit to the person for the idea. Please note that this -tag should not be added without the reporter's permission, especially if the -idea was not posted in a public forum. That said, if we diligently credit our -idea reporters, they will, hopefully, be inspired to help us again in the -future. - -A Fixes: tag indicates that the patch fixes an issue in a previous commit. It -is used to make it easy to determine where a bug originated, which can help -review a bug fix. This tag also assists the stable kernel team in determining -which stable kernel versions should receive your fix. This is the preferred -method for indicating a bug fixed by the patch. See :ref:`describe_changes` -for more details. - - -14) The canonical patch format ------------------------------- - -This section describes how the patch itself should be formatted. Note -that, if you have your patches stored in a ``git`` repository, proper patch -formatting can be had with ``git format-patch``. The tools cannot create -the necessary text, though, so read the instructions below anyway. - -The canonical patch subject line is:: - - Subject: [PATCH 001/123] subsystem: summary phrase - -The canonical patch message body contains the following: - - - A ``from`` line specifying the patch author (only needed if the person - sending the patch is not the author). - - - An empty line. - - - The body of the explanation, line wrapped at 75 columns, which will - be copied to the permanent changelog to describe this patch. - - - The ``Signed-off-by:`` lines, described above, which will - also go in the changelog. - - - A marker line containing simply ``---``. - - - Any additional comments not suitable for the changelog. - - - The actual patch (``diff`` output). - -The Subject line format makes it very easy to sort the emails -alphabetically by subject line - pretty much any email reader will -support that - since because the sequence number is zero-padded, -the numerical and alphabetic sort is the same. - -The ``subsystem`` in the email's Subject should identify which -area or subsystem of the kernel is being patched. - -The ``summary phrase`` in the email's Subject should concisely -describe the patch which that email contains. The ``summary -phrase`` should not be a filename. Do not use the same ``summary -phrase`` for every patch in a whole patch series (where a ``patch -series`` is an ordered sequence of multiple, related patches). - -Bear in mind that the ``summary phrase`` of your email becomes a -globally-unique identifier for that patch. It propagates all the way -into the ``git`` changelog. The ``summary phrase`` may later be used in -developer discussions which refer to the patch. People will want to -google for the ``summary phrase`` to read discussion regarding that -patch. It will also be the only thing that people may quickly see -when, two or three months later, they are going through perhaps -thousands of patches using tools such as ``gitk`` or ``git log ---oneline``. - -For these reasons, the ``summary`` must be no more than 70-75 -characters, and it must describe both what the patch changes, as well -as why the patch might be necessary. It is challenging to be both -succinct and descriptive, but that is what a well-written summary -should do. - -The ``summary phrase`` may be prefixed by tags enclosed in square -brackets: "Subject: [PATCH <tag>...] <summary phrase>". The tags are -not considered part of the summary phrase, but describe how the patch -should be treated. Common tags might include a version descriptor if -the multiple versions of the patch have been sent out in response to -comments (i.e., "v1, v2, v3"), or "RFC" to indicate a request for -comments. If there are four patches in a patch series the individual -patches may be numbered like this: 1/4, 2/4, 3/4, 4/4. This assures -that developers understand the order in which the patches should be -applied and that they have reviewed or applied all of the patches in -the patch series. - -A couple of example Subjects:: - - Subject: [PATCH 2/5] ext2: improve scalability of bitmap searching - Subject: [PATCH v2 01/27] x86: fix eflags tracking - -The ``from`` line must be the very first line in the message body, -and has the form: - - From: Original Author <author@example.com> - -The ``from`` line specifies who will be credited as the author of the -patch in the permanent changelog. If the ``from`` line is missing, -then the ``From:`` line from the email header will be used to determine -the patch author in the changelog. - -The explanation body will be committed to the permanent source -changelog, so should make sense to a competent reader who has long -since forgotten the immediate details of the discussion that might -have led to this patch. Including symptoms of the failure which the -patch addresses (kernel log messages, oops messages, etc.) is -especially useful for people who might be searching the commit logs -looking for the applicable patch. If a patch fixes a compile failure, -it may not be necessary to include _all_ of the compile failures; just -enough that it is likely that someone searching for the patch can find -it. As in the ``summary phrase``, it is important to be both succinct as -well as descriptive. - -The ``---`` marker line serves the essential purpose of marking for patch -handling tools where the changelog message ends. - -One good use for the additional comments after the ``---`` marker is for -a ``diffstat``, to show what files have changed, and the number of -inserted and deleted lines per file. A ``diffstat`` is especially useful -on bigger patches. Other comments relevant only to the moment or the -maintainer, not suitable for the permanent changelog, should also go -here. A good example of such comments might be ``patch changelogs`` -which describe what has changed between the v1 and v2 version of the -patch. - -If you are going to include a ``diffstat`` after the ``---`` marker, please -use ``diffstat`` options ``-p 1 -w 70`` so that filenames are listed from -the top of the kernel source tree and don't use too much horizontal -space (easily fit in 80 columns, maybe with some indentation). (``git`` -generates appropriate diffstats by default.) - -See more details on the proper patch format in the following -references. - -.. _explicit_in_reply_to: - -15) Explicit In-Reply-To headers --------------------------------- - -It can be helpful to manually add In-Reply-To: headers to a patch -(e.g., when using ``git send-email``) to associate the patch with -previous relevant discussion, e.g. to link a bug fix to the email with -the bug report. However, for a multi-patch series, it is generally -best to avoid using In-Reply-To: to link to older versions of the -series. This way multiple versions of the patch don't become an -unmanageable forest of references in email clients. If a link is -helpful, you can use the https://lkml.kernel.org/ redirector (e.g., in -the cover email text) to link to an earlier version of the patch series. - - -16) Sending ``git pull`` requests ---------------------------------- - -If you have a series of patches, it may be most convenient to have the -maintainer pull them directly into the subsystem repository with a -``git pull`` operation. Note, however, that pulling patches from a developer -requires a higher degree of trust than taking patches from a mailing list. -As a result, many subsystem maintainers are reluctant to take pull -requests, especially from new, unknown developers. If in doubt you can use -the pull request as the cover letter for a normal posting of the patch -series, giving the maintainer the option of using either. - -A pull request should have [GIT] or [PULL] in the subject line. The -request itself should include the repository name and the branch of -interest on a single line; it should look something like:: - - Please pull from - - git://jdelvare.pck.nerim.net/jdelvare-2.6 i2c-for-linus - - to get these changes: - -A pull request should also include an overall message saying what will be -included in the request, a ``git shortlog`` listing of the patches -themselves, and a ``diffstat`` showing the overall effect of the patch series. -The easiest way to get all this information together is, of course, to let -``git`` do it for you with the ``git request-pull`` command. - -Some maintainers (including Linus) want to see pull requests from signed -commits; that increases their confidence that the request actually came -from you. Linus, in particular, will not pull from public hosting sites -like GitHub in the absence of a signed tag. - -The first step toward creating such tags is to make a GNUPG key and get it -signed by one or more core kernel developers. This step can be hard for -new developers, but there is no way around it. Attending conferences can -be a good way to find developers who can sign your key. - -Once you have prepared a patch series in ``git`` that you wish to have somebody -pull, create a signed tag with ``git tag -s``. This will create a new tag -identifying the last commit in the series and containing a signature -created with your private key. You will also have the opportunity to add a -changelog-style message to the tag; this is an ideal place to describe the -effects of the pull request as a whole. - -If the tree the maintainer will be pulling from is not the repository you -are working from, don't forget to push the signed tag explicitly to the -public tree. - -When generating your pull request, use the signed tag as the target. A -command like this will do the trick:: - - git request-pull master git://my.public.tree/linux.git my-signed-tag - - -REFERENCES -********** - -Andrew Morton, "The perfect patch" (tpp). - <http://www.ozlabs.org/~akpm/stuff/tpp.txt> - -Jeff Garzik, "Linux kernel patch submission format". - <http://linux.yyz.us/patch-format.html> - -Greg Kroah-Hartman, "How to piss off a kernel subsystem maintainer". - <http://www.kroah.com/log/linux/maintainer.html> - - <http://www.kroah.com/log/linux/maintainer-02.html> - - <http://www.kroah.com/log/linux/maintainer-03.html> - - <http://www.kroah.com/log/linux/maintainer-04.html> - - <http://www.kroah.com/log/linux/maintainer-05.html> - - <http://www.kroah.com/log/linux/maintainer-06.html> - -NO!!!! No more huge patch bombs to linux-kernel@vger.kernel.org people! - <https://lkml.org/lkml/2005/7/11/336> - -Kernel Documentation/CodingStyle: - :ref:`Documentation/CodingStyle <codingstyle>` - -Linus Torvalds's mail on the canonical patch format: - <http://lkml.org/lkml/2005/4/7/183> - -Andi Kleen, "On submitting kernel patches" - Some strategies to get difficult or controversial changes in. - - http://halobates.de/on-submitting-patches.pdf - +This file has moved to process/submitting-patches.rst diff --git a/Documentation/VGA-softcursor.txt b/Documentation/VGA-softcursor.txt deleted file mode 100644 index 70acfbf..0000000 --- a/Documentation/VGA-softcursor.txt +++ /dev/null @@ -1,39 +0,0 @@ -Software cursor for VGA by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz> -======================= and Martin Mares <mj@atrey.karlin.mff.cuni.cz> - - Linux now has some ability to manipulate cursor appearance. Normally, you -can set the size of hardware cursor (and also work around some ugly bugs in -those miserable Trident cards--see #define TRIDENT_GLITCH in drivers/video/ -vgacon.c). You can now play a few new tricks: you can make your cursor look -like a non-blinking red block, make it inverse background of the character it's -over or to highlight that character and still choose whether the original -hardware cursor should remain visible or not. There may be other things I have -never thought of. - - The cursor appearance is controlled by a "<ESC>[?1;2;3c" escape sequence -where 1, 2 and 3 are parameters described below. If you omit any of them, -they will default to zeroes. - - Parameter 1 specifies cursor size (0=default, 1=invisible, 2=underline, ..., -8=full block) + 16 if you want the software cursor to be applied + 32 if you -want to always change the background color + 64 if you dislike having the -background the same as the foreground. Highlights are ignored for the last two -flags. - - The second parameter selects character attribute bits you want to change -(by simply XORing them with the value of this parameter). On standard VGA, -the high four bits specify background and the low four the foreground. In both -groups, low three bits set color (as in normal color codes used by the console) -and the most significant one turns on highlight (or sometimes blinking--it -depends on the configuration of your VGA). - - The third parameter consists of character attribute bits you want to set. -Bit setting takes place before bit toggling, so you can simply clear a bit by -including it in both the set mask and the toggle mask. - -Examples: -========= - -To get normal blinking underline, use: echo -e '\033[?2c' -To get blinking block, use: echo -e '\033[?6c' -To get red non-blinking block, use: echo -e '\033[?17;0;64c' diff --git a/Documentation/acpi/video_extension.txt b/Documentation/acpi/video_extension.txt index 78b32ac..79bf6a4 100644 --- a/Documentation/acpi/video_extension.txt +++ b/Documentation/acpi/video_extension.txt @@ -101,6 +101,6 @@ received a notification, it will set the backlight level accordingly. This does not affect the sending of event to user space, they are always sent to user space regardless of whether or not the video module controls the backlight level directly. This behaviour can be controlled through the brightness_switch_enabled -module parameter as documented in kernel-parameters.txt. It is recommended to +module parameter as documented in admin-guide/kernel-parameters.rst. It is recommended to disable this behaviour once a GUI environment starts up and wants to have full control of the backlight level. diff --git a/Documentation/admin-guide/README.rst b/Documentation/admin-guide/README.rst new file mode 100644 index 0000000..1b6dfb2 --- /dev/null +++ b/Documentation/admin-guide/README.rst @@ -0,0 +1,411 @@ +Linux kernel release 4.x <http://kernel.org/> +============================================= + +These are the release notes for Linux version 4. Read them carefully, +as they tell you what this is all about, explain how to install the +kernel, and what to do if something goes wrong. + +What is Linux? +-------------- + + Linux is a clone of the operating system Unix, written from scratch by + Linus Torvalds with assistance from a loosely-knit team of hackers across + the Net. It aims towards POSIX and Single UNIX Specification compliance. + + It has all the features you would expect in a modern fully-fledged Unix, + including true multitasking, virtual memory, shared libraries, demand + loading, shared copy-on-write executables, proper memory management, + and multistack networking including IPv4 and IPv6. + + It is distributed under the GNU General Public License - see the + accompanying COPYING file for more details. + +On what hardware does it run? +----------------------------- + + Although originally developed first for 32-bit x86-based PCs (386 or higher), + today Linux also runs on (at least) the Compaq Alpha AXP, Sun SPARC and + UltraSPARC, Motorola 68000, PowerPC, PowerPC64, ARM, Hitachi SuperH, Cell, + IBM S/390, MIPS, HP PA-RISC, Intel IA-64, DEC VAX, AMD x86-64, AXIS CRIS, + Xtensa, Tilera TILE, AVR32, ARC and Renesas M32R architectures. + + Linux is easily portable to most general-purpose 32- or 64-bit architectures + as long as they have a paged memory management unit (PMMU) and a port of the + GNU C compiler (gcc) (part of The GNU Compiler Collection, GCC). Linux has + also been ported to a number of architectures without a PMMU, although + functionality is then obviously somewhat limited. + Linux has also been ported to itself. You can now run the kernel as a + userspace application - this is called UserMode Linux (UML). + +Documentation +------------- + + - There is a lot of documentation available both in electronic form on + the Internet and in books, both Linux-specific and pertaining to + general UNIX questions. I'd recommend looking into the documentation + subdirectories on any Linux FTP site for the LDP (Linux Documentation + Project) books. This README is not meant to be documentation on the + system: there are much better sources available. + + - There are various README files in the Documentation/ subdirectory: + these typically contain kernel-specific installation notes for some + drivers for example. See Documentation/00-INDEX for a list of what + is contained in each file. Please read the + :ref:`Documentation/process/changes.rst <changes>` file, as it + contains information about the problems, which may result by upgrading + your kernel. + + - The Documentation/DocBook/ subdirectory contains several guides for + kernel developers and users. These guides can be rendered in a + number of formats: PostScript (.ps), PDF, HTML, & man-pages, among others. + After installation, ``make psdocs``, ``make pdfdocs``, ``make htmldocs``, + or ``make mandocs`` will render the documentation in the requested format. + +Installing the kernel source +---------------------------- + + - If you install the full sources, put the kernel tarball in a + directory where you have permissions (e.g. your home directory) and + unpack it:: + + xz -cd linux-4.X.tar.xz | tar xvf - + + Replace "X" with the version number of the latest kernel. + + Do NOT use the /usr/src/linux area! This area has a (usually + incomplete) set of kernel headers that are used by the library header + files. They should match the library, and not get messed up by + whatever the kernel-du-jour happens to be. + + - You can also upgrade between 4.x releases by patching. Patches are + distributed in the xz format. To install by patching, get all the + newer patch files, enter the top level directory of the kernel source + (linux-4.X) and execute:: + + xz -cd ../patch-4.x.xz | patch -p1 + + Replace "x" for all versions bigger than the version "X" of your current + source tree, **in_order**, and you should be ok. You may want to remove + the backup files (some-file-name~ or some-file-name.orig), and make sure + that there are no failed patches (some-file-name# or some-file-name.rej). + If there are, either you or I have made a mistake. + + Unlike patches for the 4.x kernels, patches for the 4.x.y kernels + (also known as the -stable kernels) are not incremental but instead apply + directly to the base 4.x kernel. For example, if your base kernel is 4.0 + and you want to apply the 4.0.3 patch, you must not first apply the 4.0.1 + and 4.0.2 patches. Similarly, if you are running kernel version 4.0.2 and + want to jump to 4.0.3, you must first reverse the 4.0.2 patch (that is, + patch -R) **before** applying the 4.0.3 patch. You can read more on this in + :ref:`Documentation/process/applying-patches.rst <applying_patches>`. + + Alternatively, the script patch-kernel can be used to automate this + process. It determines the current kernel version and applies any + patches found:: + + linux/scripts/patch-kernel linux + + The first argument in the command above is the location of the + kernel source. Patches are applied from the current directory, but + an alternative directory can be specified as the second argument. + + - Make sure you have no stale .o files and dependencies lying around:: + + cd linux + make mrproper + + You should now have the sources correctly installed. + +Software requirements +--------------------- + + Compiling and running the 4.x kernels requires up-to-date + versions of various software packages. Consult + :ref:`Documentation/process/changes.rst <changes>` for the minimum version numbers + required and how to get updates for these packages. Beware that using + excessively old versions of these packages can cause indirect + errors that are very difficult to track down, so don't assume that + you can just update packages when obvious problems arise during + build or operation. + +Build directory for the kernel +------------------------------ + + When compiling the kernel, all output files will per default be + stored together with the kernel source code. + Using the option ``make O=output/dir`` allows you to specify an alternate + place for the output files (including .config). + Example:: + + kernel source code: /usr/src/linux-4.X + build directory: /home/name/build/kernel + + To configure and build the kernel, use:: + + cd /usr/src/linux-4.X + make O=/home/name/build/kernel menuconfig + make O=/home/name/build/kernel + sudo make O=/home/name/build/kernel modules_install install + + Please note: If the ``O=output/dir`` option is used, then it must be + used for all invocations of make. + +Configuring the kernel +---------------------- + + Do not skip this step even if you are only upgrading one minor + version. New configuration options are added in each release, and + odd problems will turn up if the configuration files are not set up + as expected. If you want to carry your existing configuration to a + new version with minimal work, use ``make oldconfig``, which will + only ask you for the answers to new questions. + + - Alternative configuration commands are:: + + "make config" Plain text interface. + + "make menuconfig" Text based color menus, radiolists & dialogs. + + "make nconfig" Enhanced text based color menus. + + "make xconfig" Qt based configuration tool. + + "make gconfig" GTK+ based configuration tool. + + "make oldconfig" Default all questions based on the contents of + your existing ./.config file and asking about + new config symbols. + + "make silentoldconfig" + Like above, but avoids cluttering the screen + with questions already answered. + Additionally updates the dependencies. + + "make olddefconfig" + Like above, but sets new symbols to their default + values without prompting. + + "make defconfig" Create a ./.config file by using the default + symbol values from either arch/$ARCH/defconfig + or arch/$ARCH/configs/${PLATFORM}_defconfig, + depending on the architecture. + + "make ${PLATFORM}_defconfig" + Create a ./.config file by using the default + symbol values from + arch/$ARCH/configs/${PLATFORM}_defconfig. + Use "make help" to get a list of all available + platforms of your architecture. + + "make allyesconfig" + Create a ./.config file by setting symbol + values to 'y' as much as possible. + + "make allmodconfig" + Create a ./.config file by setting symbol + values to 'm' as much as possible. + + "make allnoconfig" Create a ./.config file by setting symbol + values to 'n' as much as possible. + + "make randconfig" Create a ./.config file by setting symbol + values to random values. + + "make localmodconfig" Create a config based on current config and + loaded modules (lsmod). Disables any module + option that is not needed for the loaded modules. + + To create a localmodconfig for another machine, + store the lsmod of that machine into a file + and pass it in as a LSMOD parameter. + + target$ lsmod > /tmp/mylsmod + target$ scp /tmp/mylsmod host:/tmp + + host$ make LSMOD=/tmp/mylsmod localmodconfig + + The above also works when cross compiling. + + "make localyesconfig" Similar to localmodconfig, except it will convert + all module options to built in (=y) options. + + You can find more information on using the Linux kernel config tools + in Documentation/kbuild/kconfig.txt. + + - NOTES on ``make config``: + + - Having unnecessary drivers will make the kernel bigger, and can + under some circumstances lead to problems: probing for a + nonexistent controller card may confuse your other controllers + + - A kernel with math-emulation compiled in will still use the + coprocessor if one is present: the math emulation will just + never get used in that case. The kernel will be slightly larger, + but will work on different machines regardless of whether they + have a math coprocessor or not. + + - The "kernel hacking" configuration details usually result in a + bigger or slower kernel (or both), and can even make the kernel + less stable by configuring some routines to actively try to + break bad code to find kernel problems (kmalloc()). Thus you + should probably answer 'n' to the questions for "development", + "experimental", or "debugging" features. + +Compiling the kernel +-------------------- + + - Make sure you have at least gcc 3.2 available. + For more information, refer to :ref:`Documentation/process/changes.rst <changes>`. + + Please note that you can still run a.out user programs with this kernel. + + - Do a ``make`` to create a compressed kernel image. It is also + possible to do ``make install`` if you have lilo installed to suit the + kernel makefiles, but you may want to check your particular lilo setup first. + + To do the actual install, you have to be root, but none of the normal + build should require that. Don't take the name of root in vain. + + - If you configured any of the parts of the kernel as ``modules``, you + will also have to do ``make modules_install``. + + - Verbose kernel compile/build output: + + Normally, the kernel build system runs in a fairly quiet mode (but not + totally silent). However, sometimes you or other kernel developers need + to see compile, link, or other commands exactly as they are executed. + For this, use "verbose" build mode. This is done by passing + ``V=1`` to the ``make`` command, e.g.:: + + make V=1 all + + To have the build system also tell the reason for the rebuild of each + target, use ``V=2``. The default is ``V=0``. + + - Keep a backup kernel handy in case something goes wrong. This is + especially true for the development releases, since each new release + contains new code which has not been debugged. Make sure you keep a + backup of the modules corresponding to that kernel, as well. If you + are installing a new kernel with the same version number as your + working kernel, make a backup of your modules directory before you + do a ``make modules_install``. + + Alternatively, before compiling, use the kernel config option + "LOCALVERSION" to append a unique suffix to the regular kernel version. + LOCALVERSION can be set in the "General Setup" menu. + + - In order to boot your new kernel, you'll need to copy the kernel + image (e.g. .../linux/arch/x86/boot/bzImage after compilation) + to the place where your regular bootable kernel is found. + + - Booting a kernel directly from a floppy without the assistance of a + bootloader such as LILO, is no longer supported. + + If you boot Linux from the hard drive, chances are you use LILO, which + uses the kernel image as specified in the file /etc/lilo.conf. The + kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or + /boot/bzImage. To use the new kernel, save a copy of the old image + and copy the new image over the old one. Then, you MUST RERUN LILO + to update the loading map! If you don't, you won't be able to boot + the new kernel image. + + Reinstalling LILO is usually a matter of running /sbin/lilo. + You may wish to edit /etc/lilo.conf to specify an entry for your + old kernel image (say, /vmlinux.old) in case the new one does not + work. See the LILO docs for more information. + + After reinstalling LILO, you should be all set. Shutdown the system, + reboot, and enjoy! + + If you ever need to change the default root device, video mode, + ramdisk size, etc. in the kernel image, use the ``rdev`` program (or + alternatively the LILO boot options when appropriate). No need to + recompile the kernel to change these parameters. + + - Reboot with the new kernel and enjoy. + +If something goes wrong +----------------------- + + - If you have problems that seem to be due to kernel bugs, please check + the file MAINTAINERS to see if there is a particular person associated + with the part of the kernel that you are having trouble with. If there + isn't anyone listed there, then the second best thing is to mail + them to me (torvalds@linux-foundation.org), and possibly to any other + relevant mailing-list or to the newsgroup. + + - In all bug-reports, *please* tell what kernel you are talking about, + how to duplicate the problem, and what your setup is (use your common + sense). If the problem is new, tell me so, and if the problem is + old, please try to tell me when you first noticed it. + + - If the bug results in a message like:: + + unable to handle kernel paging request at address C0000010 + Oops: 0002 + EIP: 0010:XXXXXXXX + eax: xxxxxxxx ebx: xxxxxxxx ecx: xxxxxxxx edx: xxxxxxxx + esi: xxxxxxxx edi: xxxxxxxx ebp: xxxxxxxx + ds: xxxx es: xxxx fs: xxxx gs: xxxx + Pid: xx, process nr: xx + xx xx xx xx xx xx xx xx xx xx + + or similar kernel debugging information on your screen or in your + system log, please duplicate it *exactly*. The dump may look + incomprehensible to you, but it does contain information that may + help debugging the problem. The text above the dump is also + important: it tells something about why the kernel dumped code (in + the above example, it's due to a bad kernel pointer). More information + on making sense of the dump is in Documentation/admin-guide/oops-tracing.rst + + - If you compiled the kernel with CONFIG_KALLSYMS you can send the dump + as is, otherwise you will have to use the ``ksymoops`` program to make + sense of the dump (but compiling with CONFIG_KALLSYMS is usually preferred). + This utility can be downloaded from + ftp://ftp.<country>.kernel.org/pub/linux/utils/kernel/ksymoops/ . + Alternatively, you can do the dump lookup by hand: + + - In debugging dumps like the above, it helps enormously if you can + look up what the EIP value means. The hex value as such doesn't help + me or anybody else very much: it will depend on your particular + kernel setup. What you should do is take the hex value from the EIP + line (ignore the ``0010:``), and look it up in the kernel namelist to + see which kernel function contains the offending address. + + To find out the kernel function name, you'll need to find the system + binary associated with the kernel that exhibited the symptom. This is + the file 'linux/vmlinux'. To extract the namelist and match it against + the EIP from the kernel crash, do:: + + nm vmlinux | sort | less + + This will give you a list of kernel addresses sorted in ascending + order, from which it is simple to find the function that contains the + offending address. Note that the address given by the kernel + debugging messages will not necessarily match exactly with the + function addresses (in fact, that is very unlikely), so you can't + just 'grep' the list: the list will, however, give you the starting + point of each kernel function, so by looking for the function that + has a starting address lower than the one you are searching for but + is followed by a function with a higher address you will find the one + you want. In fact, it may be a good idea to include a bit of + "context" in your problem report, giving a few lines around the + interesting one. + + If you for some reason cannot do the above (you have a pre-compiled + kernel image or similar), telling me as much about your setup as + possible will help. Please read the :ref:`admin-guide/reporting-bugs.rst <reportingbugs>` + document for details. + + - Alternatively, you can use gdb on a running kernel. (read-only; i.e. you + cannot change values or set break points.) To do this, first compile the + kernel with -g; edit arch/x86/Makefile appropriately, then do a ``make + clean``. You'll also need to enable CONFIG_PROC_FS (via ``make config``). + + After you've rebooted with the new kernel, do ``gdb vmlinux /proc/kcore``. + You can now use all the usual gdb commands. The command to look up the + point where your system crashed is ``l *0xXXXXXXXX``. (Replace the XXXes + with the EIP value.) + + gdb'ing a non-running kernel currently fails because ``gdb`` (wrongly) + disregards the starting offset for which the kernel is compiled. diff --git a/Documentation/bad_memory.txt b/Documentation/admin-guide/bad-memory.rst index df84162..a5c0e25 100644 --- a/Documentation/bad_memory.txt +++ b/Documentation/admin-guide/bad-memory.rst @@ -1,9 +1,10 @@ +How to deal with bad memory e.g. reported by memtest86+ ? +========================================================= + March 2008 Jan-Simon Moeller, dl9pf@gmx.de -How to deal with bad memory e.g. reported by memtest86+ ? -######################################################### There are three possibilities I know of: @@ -19,6 +20,7 @@ This Howto is about number 3) . BadRAM ###### + BadRAM is the actively developed and available as kernel-patch here: http://rick.vanrein.org/linux/badram/ @@ -31,15 +33,18 @@ memmap is already in the kernel and usable as kernel-parameter at boot-time. Its syntax is slightly strange and you may need to calculate the values by yourself! -Syntax to exclude a memory area (see kernel-parameters.txt for details): -memmap=<size>$<address> +Syntax to exclude a memory area (see admin-guide/kernel-parameters.rst for details):: + + memmap=<size>$<address> Example: memtest86+ reported here errors at address 0x18691458, 0x18698424 and - some others. All had 0x1869xxxx in common, so I chose a pattern of - 0x18690000,0xffff0000. +some others. All had 0x1869xxxx in common, so I chose a pattern of +0x18690000,0xffff0000. + +With the numbers of the example above:: + + memmap=64K$0x18690000 -With the numbers of the example above: -memmap=64K$0x18690000 - or -memmap=0x10000$0x18690000 +or:: + memmap=0x10000$0x18690000 diff --git a/Documentation/admin-guide/basic-profiling.rst b/Documentation/admin-guide/basic-profiling.rst new file mode 100644 index 0000000..72babc7 --- /dev/null +++ b/Documentation/admin-guide/basic-profiling.rst @@ -0,0 +1,68 @@ +Basic kernel profiling +====================== + + +These instructions are deliberately very basic. If you want something clever, +go read the real docs ;-) + +Please don't add more stuff, but feel free to +correct my mistakes ;-) (mbligh@aracnet.com) + +Thanks to John Levon, Dave Hansen, et al. for help writing this. + +``<test>`` is the thing you're trying to measure. +Make sure you have the correct ``System.map`` / ``vmlinux`` referenced! + +It is probably easiest to use ``make install`` for linux and hack +``/sbin/installkernel`` to copy ``vmlinux`` to ``/boot``, in addition to +``vmlinuz``, ``config``, ``System.map``, which are usually installed by default. + +Readprofile +----------- + +A recent ``readprofile`` command is needed for 2.6, such as found in util-linux +2.12a, which can be downloaded from: + + http://www.kernel.org/pub/linux/utils/util-linux/ + +Most distributions will ship it already. + +Add ``profile=2`` to the kernel command line. + +Some ``readprofile`` commands:: + + clear readprofile -r + <test> + dump output readprofile -m /boot/System.map > captured_profile + +Oprofile +-------- + +Get the source (see Changes for required version) from +http://oprofile.sourceforge.net/ and add ``idle=poll`` to the kernel command +line. + +Configure with ``CONFIG_PROFILING=y`` and ``CONFIG_OPROFILE=y`` & reboot on new kernel:: + + ./configure --with-kernel-support + make install + +For superior results, be sure to enable the local APIC. If opreport sees +a 0Hz CPU, APIC was not on. Be aware that idle=poll may mean a performance +penalty. + +One time setup:: + + opcontrol --setup --vmlinux=/boot/vmlinux + +Some ``opcontrol`` commands:: + + clear opcontrol --reset + start opcontrol --start + <test> + stop opcontrol --stop + dump output opreport > output_file + +To only report on the kernel, run ``opreport -l /boot/vmlinux > output_file`` + +A reset is needed to clear old statistics, which survive a reboot. diff --git a/Documentation/admin-guide/binfmt-misc.rst b/Documentation/admin-guide/binfmt-misc.rst new file mode 100644 index 0000000..97b0d79 --- /dev/null +++ b/Documentation/admin-guide/binfmt-misc.rst @@ -0,0 +1,151 @@ +Kernel Support for miscellaneous (your favourite) Binary Formats v1.1 +===================================================================== + +This Kernel feature allows you to invoke almost (for restrictions see below) +every program by simply typing its name in the shell. +This includes for example compiled Java(TM), Python or Emacs programs. + +To achieve this you must tell binfmt_misc which interpreter has to be invoked +with which binary. Binfmt_misc recognises the binary-type by matching some bytes +at the beginning of the file with a magic byte sequence (masking out specified +bits) you have supplied. Binfmt_misc can also recognise a filename extension +aka ``.com`` or ``.exe``. + +First you must mount binfmt_misc:: + + mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc + +To actually register a new binary type, you have to set up a string looking like +``:name:type:offset:magic:mask:interpreter:flags`` (where you can choose the +``:`` upon your needs) and echo it to ``/proc/sys/fs/binfmt_misc/register``. + +Here is what the fields mean: + +- ``name`` + is an identifier string. A new /proc file will be created with this + ``name below /proc/sys/fs/binfmt_misc``; cannot contain slashes ``/`` for + obvious reasons. +- ``type`` + is the type of recognition. Give ``M`` for magic and ``E`` for extension. +- ``offset`` + is the offset of the magic/mask in the file, counted in bytes. This + defaults to 0 if you omit it (i.e. you write ``:name:type::magic...``). + Ignored when using filename extension matching. +- ``magic`` + is the byte sequence binfmt_misc is matching for. The magic string + may contain hex-encoded characters like ``\x0a`` or ``\xA4``. Note that you + must escape any NUL bytes; parsing halts at the first one. In a shell + environment you might have to write ``\\x0a`` to prevent the shell from + eating your ``\``. + If you chose filename extension matching, this is the extension to be + recognised (without the ``.``, the ``\x0a`` specials are not allowed). + Extension matching is case sensitive, and slashes ``/`` are not allowed! +- ``mask`` + is an (optional, defaults to all 0xff) mask. You can mask out some + bits from matching by supplying a string like magic and as long as magic. + The mask is anded with the byte sequence of the file. Note that you must + escape any NUL bytes; parsing halts at the first one. Ignored when using + filename extension matching. +- ``interpreter`` + is the program that should be invoked with the binary as first + argument (specify the full path) +- ``flags`` + is an optional field that controls several aspects of the invocation + of the interpreter. It is a string of capital letters, each controls a + certain aspect. The following flags are supported: + + ``P`` - preserve-argv[0] + Legacy behavior of binfmt_misc is to overwrite + the original argv[0] with the full path to the binary. When this + flag is included, binfmt_misc will add an argument to the argument + vector for this purpose, thus preserving the original ``argv[0]``. + e.g. If your interp is set to ``/bin/foo`` and you run ``blah`` + (which is in ``/usr/local/bin``), then the kernel will execute + ``/bin/foo`` with ``argv[]`` set to ``["/bin/foo", "/usr/local/bin/blah", "blah"]``. The interp has to be aware of this so it can + execute ``/usr/local/bin/blah`` + with ``argv[]`` set to ``["blah"]``. + ``O`` - open-binary + Legacy behavior of binfmt_misc is to pass the full path + of the binary to the interpreter as an argument. When this flag is + included, binfmt_misc will open the file for reading and pass its + descriptor as an argument, instead of the full path, thus allowing + the interpreter to execute non-readable binaries. This feature + should be used with care - the interpreter has to be trusted not to + emit the contents of the non-readable binary. + ``C`` - credentials + Currently, the behavior of binfmt_misc is to calculate + the credentials and security token of the new process according to + the interpreter. When this flag is included, these attributes are + calculated according to the binary. It also implies the ``O`` flag. + This feature should be used with care as the interpreter + will run with root permissions when a setuid binary owned by root + is run with binfmt_misc. + ``F`` - fix binary + The usual behaviour of binfmt_misc is to spawn the + binary lazily when the misc format file is invoked. However, + this doesn``t work very well in the face of mount namespaces and + changeroots, so the ``F`` mode opens the binary as soon as the + emulation is installed and uses the opened image to spawn the + emulator, meaning it is always available once installed, + regardless of how the environment changes. + + +There are some restrictions: + + - the whole register string may not exceed 1920 characters + - the magic must reside in the first 128 bytes of the file, i.e. + offset+size(magic) has to be less than 128 + - the interpreter string may not exceed 127 characters + +To use binfmt_misc you have to mount it first. You can mount it with +``mount -t binfmt_misc none /proc/sys/fs/binfmt_misc`` command, or you can add +a line ``none /proc/sys/fs/binfmt_misc binfmt_misc defaults 0 0`` to your +``/etc/fstab`` so it auto mounts on boot. + +You may want to add the binary formats in one of your ``/etc/rc`` scripts during +boot-up. Read the manual of your init program to figure out how to do this +right. + +Think about the order of adding entries! Later added entries are matched first! + + +A few examples (assumed you are in ``/proc/sys/fs/binfmt_misc``): + +- enable support for em86 (like binfmt_em86, for Alpha AXP only):: + + echo ':i386:M::\x7fELF\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x03:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfb\xff\xff:/bin/em86:' > register + echo ':i486:M::\x7fELF\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x06:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfb\xff\xff:/bin/em86:' > register + +- enable support for packed DOS applications (pre-configured dosemu hdimages):: + + echo ':DEXE:M::\x0eDEX::/usr/bin/dosexec:' > register + +- enable support for Windows executables using wine:: + + echo ':DOSWin:M::MZ::/usr/local/bin/wine:' > register + +For java support see Documentation/admin-guide/java.rst + + +You can enable/disable binfmt_misc or one binary type by echoing 0 (to disable) +or 1 (to enable) to ``/proc/sys/fs/binfmt_misc/status`` or +``/proc/.../the_name``. +Catting the file tells you the current status of ``binfmt_misc/the_entry``. + +You can remove one entry or all entries by echoing -1 to ``/proc/.../the_name`` +or ``/proc/sys/fs/binfmt_misc/status``. + + +Hints +----- + +If you want to pass special arguments to your interpreter, you can +write a wrapper script for it. See Documentation/admin-guide/java.rst for an +example. + +Your interpreter should NOT look in the PATH for the filename; the kernel +passes it the full filename (or the file descriptor) to use. Using ``$PATH`` can +cause unexpected behaviour and can be a security hazard. + + +Richard Günther <rguenth@tat.physik.uni-tuebingen.de> diff --git a/Documentation/admin-guide/braille-console.rst b/Documentation/admin-guide/braille-console.rst new file mode 100644 index 0000000..18e7933 --- /dev/null +++ b/Documentation/admin-guide/braille-console.rst @@ -0,0 +1,38 @@ +Linux Braille Console +===================== + +To get early boot messages on a braille device (before userspace screen +readers can start), you first need to compile the support for the usual serial +console (see :ref:`Documentation/admin-guide/serial-console.rst <serial_console>`), and +for braille device +(in :menuselection:`Device Drivers --> Accessibility support --> Console on braille device`). + +Then you need to specify a ``console=brl``, option on the kernel command line, the +format is:: + + console=brl,serial_options... + +where ``serial_options...`` are the same as described in +:ref:`Documentation/admin-guide/serial-console.rst <serial_console>`. + +So for instance you can use ``console=brl,ttyS0`` if the braille device is connected to the first serial port, and ``console=brl,ttyS0,115200`` to +override the baud rate to 115200, etc. + +By default, the braille device will just show the last kernel message (console +mode). To review previous messages, press the Insert key to switch to the VT +review mode. In review mode, the arrow keys permit to browse in the VT content, +:kbd:`PAGE-UP`/:kbd:`PAGE-DOWN` keys go at the top/bottom of the screen, and +the :kbd:`HOME` key goes back +to the cursor, hence providing very basic screen reviewing facility. + +Sound feedback can be obtained by adding the ``braille_console.sound=1`` kernel +parameter. + +For simplicity, only one braille console can be enabled, other uses of +``console=brl,...`` will be discarded. Also note that it does not interfere with +the console selection mechanism described in +:ref:`Documentation/admin-guide/serial-console.rst <serial_console>`. + +For now, only the VisioBraille device is supported. + +Samuel Thibault <samuel.thibault@ens-lyon.org> diff --git a/Documentation/BUG-HUNTING b/Documentation/admin-guide/bug-hunting.rst index 65022a8..d35dd9f 100644 --- a/Documentation/BUG-HUNTING +++ b/Documentation/admin-guide/bug-hunting.rst @@ -1,18 +1,8 @@ -Table of contents -================= +Bug hunting ++++++++++++ Last updated: 20 December 2005 -Contents -======== - -- Introduction -- Devices not appearing -- Finding patch that caused a bug --- Finding using git-bisect --- Finding it the old way -- Fixing the bug - Introduction ============ @@ -24,7 +14,8 @@ Finding bugs is not always easy. Have a go though. If you can't find it don't give up. Report as much as you have found to the relevant maintainer. See MAINTAINERS for who that is for the subsystem you have worked on. -Before you submit a bug report read REPORTING-BUGS. +Before you submit a bug report read +:ref:`Documentation/admin-guide/reporting-bugs.rst <reportingbugs>`. Devices not appearing ===================== @@ -37,15 +28,16 @@ Finding patch that caused a bug -Finding using git-bisect ------------------------- +Finding using ``git-bisect`` +---------------------------- -Using the provided tools with git makes finding bugs easy provided the bug is -reproducible. +Using the provided tools with ``git`` makes finding bugs easy provided the bug +is reproducible. Steps to do it: + - start using git for the kernel source -- read the man page for git-bisect +- read the man page for ``git-bisect`` - have fun Finding it the old way @@ -58,22 +50,22 @@ It's a brute force approach but it works pretty well. You need: - . A reproducible bug - it has to happen predictably (sorry) - . All the kernel tar files from a revision that worked to the + - A reproducible bug - it has to happen predictably (sorry) + - All the kernel tar files from a revision that worked to the revision that doesn't You will then do: - . Rebuild a revision that you believe works, install, and verify that. - . Do a binary search over the kernels to figure out which one + - Rebuild a revision that you believe works, install, and verify that. + - Do a binary search over the kernels to figure out which one introduced the bug. I.e., suppose 1.3.28 didn't have the bug, but you know that 1.3.69 does. Pick a kernel in the middle and build that, like 1.3.50. Build & test; if it works, pick the mid point between .50 and .69, else the mid point between .28 and .50. - . You'll narrow it down to the kernel that introduced the bug. You + - You'll narrow it down to the kernel that introduced the bug. You can probably do better than this but it gets tricky. - . Narrow it down to a subdirectory + - Narrow it down to a subdirectory - Copy kernel that works into "test". Let's say that 3.62 works, but 3.63 doesn't. So you diff -r those two kernels and come @@ -83,7 +75,7 @@ You will then do: Copy the non-working directory next to the working directory as "dir.63". One directory at time, try moving the working directory to - "dir.62" and mv dir.63 dir"time, try + "dir.62" and mv dir.63 dir"time, try:: mv dir dir.62 mv dir.63 dir @@ -97,15 +89,15 @@ You will then do: found in my case that they were self explanatory - you may or may not want to give up when that happens. - . Narrow it down to a file + - Narrow it down to a file - You can apply the same technique to each file in the directory, hoping that the changes in that file are self contained. - . Narrow it down to a routine + - Narrow it down to a routine - You can take the old file and the new file and manually create - a merged file that has + a merged file that has:: #ifdef VER62 routine() @@ -120,7 +112,7 @@ You will then do: #endif And then walk through that file, one routine at a time and - prefix it with + prefix it with:: #define VER62 /* both routines here */ @@ -153,94 +145,105 @@ To debug a kernel, use objdump and look for the hex offset from the crash output to find the valid line of code/assembler. Without debug symbols, you will see the assembler code for the routine shown, but if your kernel has debug symbols the C code will also be available. (Debug symbols can be enabled -in the kernel hacking menu of the menu configuration.) For example: +in the kernel hacking menu of the menu configuration.) For example:: objdump -r -S -l --disassemble net/dccp/ipv4.o -NB.: you need to be at the top level of the kernel tree for this to pick up -your C files. +.. note:: + + You need to be at the top level of the kernel tree for this to pick up + your C files. If you don't have access to the code you can also debug on some crash dumps -e.g. crash dump output as shown by Dave Miller. - -> EIP is at ip_queue_xmit+0x14/0x4c0 -> ... -> Code: 44 24 04 e8 6f 05 00 00 e9 e8 fe ff ff 8d 76 00 8d bc 27 00 00 -> 00 00 55 57 56 53 81 ec bc 00 00 00 8b ac 24 d0 00 00 00 8b 5d 08 -> <8b> 83 3c 01 00 00 89 44 24 14 8b 45 28 85 c0 89 44 24 18 0f 85 -> -> Put the bytes into a "foo.s" file like this: -> -> .text -> .globl foo -> foo: -> .byte .... /* bytes from Code: part of OOPS dump */ -> -> Compile it with "gcc -c -o foo.o foo.s" then look at the output of -> "objdump --disassemble foo.o". -> -> Output: -> -> ip_queue_xmit: -> push %ebp -> push %edi -> push %esi -> push %ebx -> sub $0xbc, %esp -> mov 0xd0(%esp), %ebp ! %ebp = arg0 (skb) -> mov 0x8(%ebp), %ebx ! %ebx = skb->sk -> mov 0x13c(%ebx), %eax ! %eax = inet_sk(sk)->opt +e.g. crash dump output as shown by Dave Miller:: + + EIP is at ip_queue_xmit+0x14/0x4c0 + ... + Code: 44 24 04 e8 6f 05 00 00 e9 e8 fe ff ff 8d 76 00 8d bc 27 00 00 + 00 00 55 57 56 53 81 ec bc 00 00 00 8b ac 24 d0 00 00 00 8b 5d 08 + <8b> 83 3c 01 00 00 89 44 24 14 8b 45 28 85 c0 89 44 24 18 0f 85 + + Put the bytes into a "foo.s" file like this: + + .text + .globl foo + foo: + .byte .... /* bytes from Code: part of OOPS dump */ + + Compile it with "gcc -c -o foo.o foo.s" then look at the output of + "objdump --disassemble foo.o". + + Output: + + ip_queue_xmit: + push %ebp + push %edi + push %esi + push %ebx + sub $0xbc, %esp + mov 0xd0(%esp), %ebp ! %ebp = arg0 (skb) + mov 0x8(%ebp), %ebx ! %ebx = skb->sk + mov 0x13c(%ebx), %eax ! %eax = inet_sk(sk)->opt In addition, you can use GDB to figure out the exact file and line -number of the OOPS from the vmlinux file. If you have -CONFIG_DEBUG_INFO enabled, you can simply copy the EIP value from the -OOPS: +number of the OOPS from the ``vmlinux`` file. If you have +``CONFIG_DEBUG_INFO`` enabled, you can simply copy the EIP value from the +OOPS:: EIP: 0060:[<c021e50e>] Not tainted VLI -And use GDB to translate that to human-readable form: +And use GDB to translate that to human-readable form:: gdb vmlinux (gdb) l *0xc021e50e -If you don't have CONFIG_DEBUG_INFO enabled, you use the function -offset from the OOPS: +If you don't have ``CONFIG_DEBUG_INFO`` enabled, you use the function +offset from the OOPS:: EIP is at vt_ioctl+0xda8/0x1482 -And recompile the kernel with CONFIG_DEBUG_INFO enabled: +And recompile the kernel with ``CONFIG_DEBUG_INFO`` enabled:: make vmlinux gdb vmlinux (gdb) p vt_ioctl (gdb) l *(0x<address of vt_ioctl> + 0xda8) -or, as one command + +or, as one command:: + (gdb) l *(vt_ioctl + 0xda8) -If you have a call trace, such as :- ->Call Trace: -> [<ffffffff8802c8e9>] :jbd:log_wait_commit+0xa3/0xf5 -> [<ffffffff810482d9>] autoremove_wake_function+0x0/0x2e -> [<ffffffff8802770b>] :jbd:journal_stop+0x1be/0x1ee -> ... +If you have a call trace, such as:: + + Call Trace: + [<ffffffff8802c8e9>] :jbd:log_wait_commit+0xa3/0xf5 + [<ffffffff810482d9>] autoremove_wake_function+0x0/0x2e + [<ffffffff8802770b>] :jbd:journal_stop+0x1be/0x1ee + ... + this shows the problem in the :jbd: module. You can load that module in gdb -and list the relevant code. +and list the relevant code:: + gdb fs/jbd/jbd.ko (gdb) p log_wait_commit (gdb) l *(0x<address> + 0xa3) -or + +or:: + (gdb) l *(log_wait_commit + 0xa3) Another very useful option of the Kernel Hacking section in menuconfig is Debug memory allocations. This will help you see whether data has been initialised and not set before use etc. To see the values that get assigned -with this look at mm/slab.c and search for POISON_INUSE. When using this an -Oops will often show the poisoned data instead of zero which is the default. +with this look at ``mm/slab.c`` and search for ``POISON_INUSE``. When using +this an Oops will often show the poisoned data instead of zero which is the +default. Once you have worked out a fix please submit it upstream. After all open source is about sharing what you do and don't you want to be recognised for your genius? -Please do read Documentation/SubmittingPatches though to help your code get -accepted. +Please do read +ref:`Documentation/process/submitting-patches.rst <submittingpatches>` though +to help your code get accepted. diff --git a/Documentation/admin-guide/conf.py b/Documentation/admin-guide/conf.py new file mode 100644 index 0000000..86f7389 --- /dev/null +++ b/Documentation/admin-guide/conf.py @@ -0,0 +1,10 @@ +# -*- coding: utf-8; mode: python -*- + +project = 'Linux Kernel User Documentation' + +tags.add("subproject") + +latex_documents = [ + ('index', 'linux-user.tex', 'Linux Kernel User Documentation', + 'The kernel development community', 'manual'), +] diff --git a/Documentation/devices.txt b/Documentation/admin-guide/devices.rst index 4035eca..89db341 100644 --- a/Documentation/devices.txt +++ b/Documentation/admin-guide/devices.rst @@ -1,14 +1,16 @@ - LINUX ALLOCATED DEVICES (4.x+ version) +Linux allocated devices (4.x+ version) +====================================== This list is the Linux Device List, the official registry of allocated -device numbers and /dev directory nodes for the Linux operating +device numbers and ``/dev`` directory nodes for the Linux operating system. The LaTeX version of this document is no longer maintained, nor is the document that used to reside at lanana.org. This version in the mainline Linux kernel is the master document. Updates shall be sent -as patches to the kernel maintainers (see the SubmittingPatches document). +as patches to the kernel maintainers (see the +:ref:`Documentation/process/submitting-patches.rst <submittingpatches>` document). Specifically explore the sections titled "CHAR and MISC DRIVERS", and "BLOCK LAYER" in the MAINTAINERS file to find the right maintainers to involve for character and block devices. @@ -26,38 +28,41 @@ permission of the authors, assuming the authors can be contacted without an unreasonable effort. - **** DEVICE DRIVERS AUTHORS PLEASE READ THIS **** +.. attention:: -Linux now has extensive support for dynamic allocation of device numbering -and can use sysfs and udev (systemd) to handle the naming needs. There are -still some exceptions in the serial and boot device area. Before asking -for a device number make sure you actually need one. + DEVICE DRIVERS AUTHORS PLEASE READ THIS -To have a major number allocated, or a minor number in situations -where that applies (e.g. busmice), please submit a patch and send to -the authors as indicated above. + Linux now has extensive support for dynamic allocation of device numbering + and can use ``sysfs`` and ``udev`` (``systemd``) to handle the naming needs. + There are still some exceptions in the serial and boot device area. Before + asking for a device number make sure you actually need one. -Keep the description of the device *in the same format -as this list*. The reason for this is that it is the only way we have -found to ensure we have all the requisite information to publish your -device and avoid conflicts. + To have a major number allocated, or a minor number in situations + where that applies (e.g. busmice), please submit a patch and send to + the authors as indicated above. -Finally, sometimes we have to play "namespace police." Please don't be -offended. We often get submissions for /dev names that would be bound -to cause conflicts down the road. We are trying to avoid getting in a -situation where we would have to suffer an incompatible forward -change. Therefore, please consult with us *before* you make your -device names and numbers in any way public, at least to the point -where it would be at all difficult to get them changed. + Keep the description of the device *in the same format + as this list*. The reason for this is that it is the only way we have + found to ensure we have all the requisite information to publish your + device and avoid conflicts. -Your cooperation is appreciated. + Finally, sometimes we have to play "namespace police." Please don't be + offended. We often get submissions for ``/dev`` names that would be bound + to cause conflicts down the road. We are trying to avoid getting in a + situation where we would have to suffer an incompatible forward + change. Therefore, please consult with us **before** you make your + device names and numbers in any way public, at least to the point + where it would be at all difficult to get them changed. + Your cooperation is appreciated. - 0 Unnamed devices (e.g. non-device mounts) +:: + + 0 Unnamed devices (e.g. non-device mounts) 0 = reserved as null device number See block major 144, 145, 146 for expansion areas. - 1 char Memory devices + 1 char Memory devices 1 = /dev/mem Physical memory access 2 = /dev/kmem Kernel virtual memory access 3 = /dev/null Null device @@ -72,7 +77,7 @@ Your cooperation is appreciated. export the buffered printk records. 12 = /dev/oldmem OBSOLETE - replaced by /proc/vmcore - 1 block RAM disk + 1 block RAM disk 0 = /dev/ram0 First RAM disk 1 = /dev/ram1 Second RAM disk ... @@ -83,7 +88,7 @@ Your cooperation is appreciated. by the boot loader; newer kernels use /dev/ram0 for the initrd. - 2 char Pseudo-TTY masters + 2 char Pseudo-TTY masters 0 = /dev/ptyp0 First PTY master 1 = /dev/ptyp1 Second PTY master ... @@ -101,7 +106,7 @@ Your cooperation is appreciated. master multiplex (/dev/ptmx) to acquire a PTY on demand. - 2 block Floppy disks + 2 block Floppy disks 0 = /dev/fd0 Controller 0, drive 0, autodetect 1 = /dev/fd1 Controller 0, drive 1, autodetect 2 = /dev/fd2 Controller 0, drive 2, autodetect @@ -158,7 +163,7 @@ Your cooperation is appreciated. and E for the 3.5" models have been deprecated, since the drive type is insignificant for these devices. - 3 char Pseudo-TTY slaves + 3 char Pseudo-TTY slaves 0 = /dev/ttyp0 First PTY slave 1 = /dev/ttyp1 Second PTY slave ... @@ -167,7 +172,7 @@ Your cooperation is appreciated. These are the old-style (BSD) PTY devices; Unix98 devices are on major 136 and above. - 3 block First MFM, RLL and IDE hard disk/CD-ROM interface + 3 block First MFM, RLL and IDE hard disk/CD-ROM interface 0 = /dev/hda Master: whole disk (or CD-ROM) 64 = /dev/hdb Slave: whole disk (or CD-ROM) @@ -183,7 +188,7 @@ Your cooperation is appreciated. Other versions of Linux use partitioning schemes appropriate to their respective architectures. - 4 char TTY devices + 4 char TTY devices 0 = /dev/tty0 Current virtual console 1 = /dev/tty1 First virtual console @@ -199,13 +204,13 @@ Your cooperation is appreciated. number for BSD PTY devices. As of Linux 2.1.115, this is no longer supported. Use major numbers 2 and 3. - 4 block Aliases for dynamically allocated major devices to be used + 4 block Aliases for dynamically allocated major devices to be used when its not possible to create the real device nodes because the root filesystem is mounted read-only. - 0 = /dev/root + 0 = /dev/root - 5 char Alternate TTY devices + 5 char Alternate TTY devices 0 = /dev/tty Current TTY device 1 = /dev/console System console 2 = /dev/ptmx PTY master multiplex @@ -218,7 +223,7 @@ Your cooperation is appreciated. the section on terminal devices for more information on /dev/console. - 6 char Parallel printer devices + 6 char Parallel printer devices 0 = /dev/lp0 Parallel printer on parport0 1 = /dev/lp1 Parallel printer on parport1 ... @@ -227,7 +232,7 @@ Your cooperation is appreciated. between parallel ports and I/O addresses. Instead, they are redirected through the parport multiplex layer. - 7 char Virtual console capture devices + 7 char Virtual console capture devices 0 = /dev/vcs Current vc text contents 1 = /dev/vcs1 tty1 text contents ... @@ -239,7 +244,7 @@ Your cooperation is appreciated. NOTE: These devices permit both read and write access. - 7 block Loopback devices + 7 block Loopback devices 0 = /dev/loop0 First loop device 1 = /dev/loop1 Second loop device ... @@ -248,7 +253,7 @@ Your cooperation is appreciated. associated with block devices. The binding to the loop devices is handled by mount(8) or losetup(8). - 8 block SCSI disk devices (0-15) + 8 block SCSI disk devices (0-15) 0 = /dev/sda First SCSI disk whole disk 16 = /dev/sdb Second SCSI disk whole disk 32 = /dev/sdc Third SCSI disk whole disk @@ -259,7 +264,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 9 char SCSI tape devices + 9 char SCSI tape devices 0 = /dev/st0 First SCSI tape, mode 0 1 = /dev/st1 Second SCSI tape, mode 0 ... @@ -290,7 +295,7 @@ Your cooperation is appreciated. ioctl()'s can be used to rewind the tape regardless of the device used to access it. - 9 block Metadisk (RAID) devices + 9 block Metadisk (RAID) devices 0 = /dev/md0 First metadisk group 1 = /dev/md1 Second metadisk group ... @@ -298,7 +303,7 @@ Your cooperation is appreciated. The metadisk driver is used to span a filesystem across multiple physical disks. - 10 char Non-serial mice, misc features + 10 char Non-serial mice, misc features 0 = /dev/logibm Logitech bus mouse 1 = /dev/psaux PS/2-style mouse port 2 = /dev/inportbm Microsoft Inport bus mouse @@ -428,22 +433,22 @@ Your cooperation is appreciated. 240-254 Reserved for local use 255 Reserved for MISC_DYNAMIC_MINOR - 11 char Raw keyboard device (Linux/SPARC only) + 11 char Raw keyboard device (Linux/SPARC only) 0 = /dev/kbd Raw keyboard device - 11 char Serial Mux device (Linux/PA-RISC only) + 11 char Serial Mux device (Linux/PA-RISC only) 0 = /dev/ttyB0 First mux port 1 = /dev/ttyB1 Second mux port ... - 11 block SCSI CD-ROM devices + 11 block SCSI CD-ROM devices 0 = /dev/scd0 First SCSI CD-ROM 1 = /dev/scd1 Second SCSI CD-ROM ... The prefix /dev/sr (instead of /dev/scd) has been deprecated. - 12 char QIC-02 tape + 12 char QIC-02 tape 2 = /dev/ntpqic11 QIC-11, no rewind-on-close 3 = /dev/tpqic11 QIC-11, rewind-on-close 4 = /dev/ntpqic24 QIC-24, no rewind-on-close @@ -456,9 +461,9 @@ Your cooperation is appreciated. The device names specified are proposed -- if there are "standard" names for these devices, please let me know. - 12 block + 12 block - 13 char Input core + 13 char Input core 0 = /dev/input/js0 First joystick 1 = /dev/input/js1 Second joystick ... @@ -472,10 +477,10 @@ Your cooperation is appreciated. Each device type has 5 bits (32 minors). - 13 block Previously used for the XT disk (/dev/xdN) + 13 block Previously used for the XT disk (/dev/xdN) Deleted in kernel v3.9. - 14 char Open Sound System (OSS) + 14 char Open Sound System (OSS) 0 = /dev/mixer Mixer control 1 = /dev/sequencer Audio sequencer 2 = /dev/midi00 First MIDI port @@ -493,44 +498,44 @@ Your cooperation is appreciated. 34 = /dev/midi02 Third MIDI port 50 = /dev/midi03 Fourth MIDI port - 14 block + 14 block - 15 char Joystick + 15 char Joystick 0 = /dev/js0 First analog joystick 1 = /dev/js1 Second analog joystick ... 128 = /dev/djs0 First digital joystick 129 = /dev/djs1 Second digital joystick ... - 15 block Sony CDU-31A/CDU-33A CD-ROM + 15 block Sony CDU-31A/CDU-33A CD-ROM 0 = /dev/sonycd Sony CDU-31a CD-ROM - 16 char Non-SCSI scanners + 16 char Non-SCSI scanners 0 = /dev/gs4500 Genius 4500 handheld scanner - 16 block GoldStar CD-ROM + 16 block GoldStar CD-ROM 0 = /dev/gscd GoldStar CD-ROM - 17 char OBSOLETE (was Chase serial card) + 17 char OBSOLETE (was Chase serial card) 0 = /dev/ttyH0 First Chase port 1 = /dev/ttyH1 Second Chase port ... - 17 block Optics Storage CD-ROM + 17 block Optics Storage CD-ROM 0 = /dev/optcd Optics Storage CD-ROM - 18 char OBSOLETE (was Chase serial card - alternate devices) + 18 char OBSOLETE (was Chase serial card - alternate devices) 0 = /dev/cuh0 Callout device for ttyH0 1 = /dev/cuh1 Callout device for ttyH1 ... - 18 block Sanyo CD-ROM + 18 block Sanyo CD-ROM 0 = /dev/sjcd Sanyo CD-ROM - 19 char Cyclades serial card + 19 char Cyclades serial card 0 = /dev/ttyC0 First Cyclades port ... 31 = /dev/ttyC31 32nd Cyclades port - 19 block "Double" compressed disk + 19 block "Double" compressed disk 0 = /dev/double0 First compressed disk ... 7 = /dev/double7 Eighth compressed disk @@ -541,15 +546,15 @@ Your cooperation is appreciated. See the Double documentation for the meaning of the mirror devices. - 20 char Cyclades serial card - alternate devices + 20 char Cyclades serial card - alternate devices 0 = /dev/cub0 Callout device for ttyC0 ... 31 = /dev/cub31 Callout device for ttyC31 - 20 block Hitachi CD-ROM (under development) + 20 block Hitachi CD-ROM (under development) 0 = /dev/hitcd Hitachi CD-ROM - 21 char Generic SCSI access + 21 char Generic SCSI access 0 = /dev/sg0 First generic SCSI device 1 = /dev/sg1 Second generic SCSI device ... @@ -559,7 +564,7 @@ Your cooperation is appreciated. the system and is counter to standard Linux device-naming practice. - 21 block Acorn MFM hard drive interface + 21 block Acorn MFM hard drive interface 0 = /dev/mfma First MFM drive whole disk 64 = /dev/mfmb Second MFM drive whole disk @@ -567,25 +572,25 @@ Your cooperation is appreciated. Partitions are handled the same way as for IDE disks (see major number 3). - 22 char Digiboard serial card + 22 char Digiboard serial card 0 = /dev/ttyD0 First Digiboard port 1 = /dev/ttyD1 Second Digiboard port ... - 22 block Second IDE hard disk/CD-ROM interface + 22 block Second IDE hard disk/CD-ROM interface 0 = /dev/hdc Master: whole disk (or CD-ROM) 64 = /dev/hdd Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 23 char Digiboard serial card - alternate devices + 23 char Digiboard serial card - alternate devices 0 = /dev/cud0 Callout device for ttyD0 1 = /dev/cud1 Callout device for ttyD1 ... - 23 block Mitsumi proprietary CD-ROM + 23 block Mitsumi proprietary CD-ROM 0 = /dev/mcd Mitsumi CD-ROM - 24 char Stallion serial card + 24 char Stallion serial card 0 = /dev/ttyE0 Stallion port 0 card 0 1 = /dev/ttyE1 Stallion port 1 card 0 ... @@ -598,10 +603,10 @@ Your cooperation is appreciated. 192 = /dev/ttyE192 Stallion port 0 card 3 193 = /dev/ttyE193 Stallion port 1 card 3 ... - 24 block Sony CDU-535 CD-ROM + 24 block Sony CDU-535 CD-ROM 0 = /dev/cdu535 Sony CDU-535 CD-ROM - 25 char Stallion serial card - alternate devices + 25 char Stallion serial card - alternate devices 0 = /dev/cue0 Callout device for ttyE0 1 = /dev/cue1 Callout device for ttyE1 ... @@ -614,21 +619,21 @@ Your cooperation is appreciated. 192 = /dev/cue192 Callout device for ttyE192 193 = /dev/cue193 Callout device for ttyE193 ... - 25 block First Matsushita (Panasonic/SoundBlaster) CD-ROM + 25 block First Matsushita (Panasonic/SoundBlaster) CD-ROM 0 = /dev/sbpcd0 Panasonic CD-ROM controller 0 unit 0 1 = /dev/sbpcd1 Panasonic CD-ROM controller 0 unit 1 2 = /dev/sbpcd2 Panasonic CD-ROM controller 0 unit 2 3 = /dev/sbpcd3 Panasonic CD-ROM controller 0 unit 3 - 26 char + 26 char - 26 block Second Matsushita (Panasonic/SoundBlaster) CD-ROM + 26 block Second Matsushita (Panasonic/SoundBlaster) CD-ROM 0 = /dev/sbpcd4 Panasonic CD-ROM controller 1 unit 0 1 = /dev/sbpcd5 Panasonic CD-ROM controller 1 unit 1 2 = /dev/sbpcd6 Panasonic CD-ROM controller 1 unit 2 3 = /dev/sbpcd7 Panasonic CD-ROM controller 1 unit 3 - 27 char QIC-117 tape + 27 char QIC-117 tape 0 = /dev/qft0 Unit 0, rewind-on-close 1 = /dev/qft1 Unit 1, rewind-on-close 2 = /dev/qft2 Unit 2, rewind-on-close @@ -654,29 +659,29 @@ Your cooperation is appreciated. 38 = /dev/nrawqft2 Unit 2, no rewind-on-close, no file marks 39 = /dev/nrawqft3 Unit 3, no rewind-on-close, no file marks - 27 block Third Matsushita (Panasonic/SoundBlaster) CD-ROM + 27 block Third Matsushita (Panasonic/SoundBlaster) CD-ROM 0 = /dev/sbpcd8 Panasonic CD-ROM controller 2 unit 0 1 = /dev/sbpcd9 Panasonic CD-ROM controller 2 unit 1 2 = /dev/sbpcd10 Panasonic CD-ROM controller 2 unit 2 3 = /dev/sbpcd11 Panasonic CD-ROM controller 2 unit 3 - 28 char Stallion serial card - card programming + 28 char Stallion serial card - card programming 0 = /dev/staliomem0 First Stallion card I/O memory 1 = /dev/staliomem1 Second Stallion card I/O memory 2 = /dev/staliomem2 Third Stallion card I/O memory 3 = /dev/staliomem3 Fourth Stallion card I/O memory - 28 char Atari SLM ACSI laser printer (68k/Atari) + 28 char Atari SLM ACSI laser printer (68k/Atari) 0 = /dev/slm0 First SLM laser printer 1 = /dev/slm1 Second SLM laser printer ... - 28 block Fourth Matsushita (Panasonic/SoundBlaster) CD-ROM + 28 block Fourth Matsushita (Panasonic/SoundBlaster) CD-ROM 0 = /dev/sbpcd12 Panasonic CD-ROM controller 3 unit 0 1 = /dev/sbpcd13 Panasonic CD-ROM controller 3 unit 1 2 = /dev/sbpcd14 Panasonic CD-ROM controller 3 unit 2 3 = /dev/sbpcd15 Panasonic CD-ROM controller 3 unit 3 - 28 block ACSI disk (68k/Atari) + 28 block ACSI disk (68k/Atari) 0 = /dev/ada First ACSI disk whole disk 16 = /dev/adb Second ACSI disk whole disk 32 = /dev/adc Third ACSI disk whole disk @@ -687,16 +692,16 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15, like SCSI. - 29 char Universal frame buffer + 29 char Universal frame buffer 0 = /dev/fb0 First frame buffer 1 = /dev/fb1 Second frame buffer ... 31 = /dev/fb31 32nd frame buffer - 29 block Aztech/Orchid/Okano/Wearnes CD-ROM + 29 block Aztech/Orchid/Okano/Wearnes CD-ROM 0 = /dev/aztcd Aztech CD-ROM - 30 char iBCS-2 compatibility devices + 30 char iBCS-2 compatibility devices 0 = /dev/socksys Socket access 1 = /dev/spx SVR3 local X interface 32 = /dev/inet/ip Network access @@ -727,17 +732,17 @@ Your cooperation is appreciated. /dev/nfsd -> /dev/socksys /dev/X0R -> /dev/null (? apparently not required ?) - 30 block Philips LMS CM-205 CD-ROM + 30 block Philips LMS CM-205 CD-ROM 0 = /dev/cm205cd Philips LMS CM-205 CD-ROM /dev/lmscd is an older name for this device. This driver does not work with the CM-205MS CD-ROM. - 31 char MPU-401 MIDI + 31 char MPU-401 MIDI 0 = /dev/mpu401data MPU-401 data port 1 = /dev/mpu401stat MPU-401 status port - 31 block ROM/flash memory card + 31 block ROM/flash memory card 0 = /dev/rom0 First ROM card (rw) ... 7 = /dev/rom7 Eighth ROM card (rw) @@ -756,25 +761,25 @@ Your cooperation is appreciated. devices. The read-only devices (ro) support reading only. - 32 char Specialix serial card + 32 char Specialix serial card 0 = /dev/ttyX0 First Specialix port 1 = /dev/ttyX1 Second Specialix port ... - 32 block Philips LMS CM-206 CD-ROM + 32 block Philips LMS CM-206 CD-ROM 0 = /dev/cm206cd Philips LMS CM-206 CD-ROM - 33 char Specialix serial card - alternate devices + 33 char Specialix serial card - alternate devices 0 = /dev/cux0 Callout device for ttyX0 1 = /dev/cux1 Callout device for ttyX1 ... - 33 block Third IDE hard disk/CD-ROM interface + 33 block Third IDE hard disk/CD-ROM interface 0 = /dev/hde Master: whole disk (or CD-ROM) 64 = /dev/hdf Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 34 char Z8530 HDLC driver + 34 char Z8530 HDLC driver 0 = /dev/scc0 First Z8530, first port 1 = /dev/scc1 First Z8530, second port 2 = /dev/scc2 Second Z8530, first port @@ -785,14 +790,14 @@ Your cooperation is appreciated. /dev/sc1 for /dev/scc0, /dev/sc2 for /dev/scc1, and so on. - 34 block Fourth IDE hard disk/CD-ROM interface + 34 block Fourth IDE hard disk/CD-ROM interface 0 = /dev/hdg Master: whole disk (or CD-ROM) 64 = /dev/hdh Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 35 char tclmidi MIDI driver + 35 char tclmidi MIDI driver 0 = /dev/midi0 First MIDI port, kernel timed 1 = /dev/midi1 Second MIDI port, kernel timed 2 = /dev/midi2 Third MIDI port, kernel timed @@ -806,10 +811,10 @@ Your cooperation is appreciated. 130 = /dev/smpte2 Third MIDI port, SMPTE timed 131 = /dev/smpte3 Fourth MIDI port, SMPTE timed - 35 block Slow memory ramdisk + 35 block Slow memory ramdisk 0 = /dev/slram Slow memory ramdisk - 36 char Netlink support + 36 char Netlink support 0 = /dev/route Routing, device updates, kernel to user 1 = /dev/skip enSKIP security cache control 3 = /dev/fwmonitor Firewall packet copies @@ -817,9 +822,9 @@ Your cooperation is appreciated. ... 31 = /dev/tap15 16th Ethertap device - 36 block OBSOLETE (was MCA ESDI hard disk) + 36 block OBSOLETE (was MCA ESDI hard disk) - 37 char IDE tape + 37 char IDE tape 0 = /dev/ht0 First IDE tape 1 = /dev/ht1 Second IDE tape ... @@ -829,10 +834,10 @@ Your cooperation is appreciated. Currently, only one IDE tape drive is supported. - 37 block Zorro II ramdisk + 37 block Zorro II ramdisk 0 = /dev/z2ram Zorro II ramdisk - 38 char Myricom PCI Myrinet board + 38 char Myricom PCI Myrinet board 0 = /dev/mlanai0 First Myrinet board 1 = /dev/mlanai1 Second Myrinet board ... @@ -841,9 +846,9 @@ Your cooperation is appreciated. and "user level packet I/O." This board is also accessible as a standard networking "eth" device. - 38 block OBSOLETE (was Linux/AP+) + 38 block OBSOLETE (was Linux/AP+) - 39 char ML-16P experimental I/O board + 39 char ML-16P experimental I/O board 0 = /dev/ml16pa-a0 First card, first analog channel 1 = /dev/ml16pa-a1 First card, second analog channel ... @@ -861,20 +866,20 @@ Your cooperation is appreciated. 50 = /dev/ml16pb-c1 Second card, second counter/timer 51 = /dev/ml16pb-c2 Second card, third counter/timer ... - 39 block + 39 block - 40 char + 40 char - 40 block + 40 block - 41 char Yet Another Micro Monitor + 41 char Yet Another Micro Monitor 0 = /dev/yamm Yet Another Micro Monitor - 41 block + 41 block - 42 char Demo/sample use + 42 char Demo/sample use - 42 block Demo/sample use + 42 block Demo/sample use This number is intended for use in sample code, as well as a general "example" device number. It @@ -887,12 +892,12 @@ Your cooperation is appreciated. IN PARTICULAR, ANY DISTRIBUTION WHICH CONTAINS A DEVICE DRIVER USING MAJOR NUMBER 42 IS NONCOMPLIANT. - 43 char isdn4linux virtual modem + 43 char isdn4linux virtual modem 0 = /dev/ttyI0 First virtual modem ... 63 = /dev/ttyI63 64th virtual modem - 43 block Network block devices + 43 block Network block devices 0 = /dev/nb0 First network block device 1 = /dev/nb1 Second network block device ... @@ -904,12 +909,12 @@ Your cooperation is appreciated. to mounting filesystems over the net, swapping over the net, implementing block device in userland etc. - 44 char isdn4linux virtual modem - alternate devices + 44 char isdn4linux virtual modem - alternate devices 0 = /dev/cui0 Callout device for ttyI0 ... 63 = /dev/cui63 Callout device for ttyI63 - 44 block Flash Translation Layer (FTL) filesystems + 44 block Flash Translation Layer (FTL) filesystems 0 = /dev/ftla FTL on first Memory Technology Device 16 = /dev/ftlb FTL on second Memory Technology Device 32 = /dev/ftlc FTL on third Memory Technology Device @@ -920,7 +925,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the partition limit is 15 rather than 63 per disk (same as SCSI.) - 45 char isdn4linux ISDN BRI driver + 45 char isdn4linux ISDN BRI driver 0 = /dev/isdn0 First virtual B channel raw data ... 63 = /dev/isdn63 64th virtual B channel raw data @@ -934,7 +939,7 @@ Your cooperation is appreciated. 255 = /dev/isdninfo ISDN monitor interface - 45 block Parallel port IDE disk devices + 45 block Parallel port IDE disk devices 0 = /dev/pda First parallel port IDE disk 16 = /dev/pdb Second parallel port IDE disk 32 = /dev/pdc Third parallel port IDE disk @@ -944,21 +949,21 @@ Your cooperation is appreciated. disks (see major number 3) except that the partition limit is 15 rather than 63 per disk. - 46 char Comtrol Rocketport serial card + 46 char Comtrol Rocketport serial card 0 = /dev/ttyR0 First Rocketport port 1 = /dev/ttyR1 Second Rocketport port ... - 46 block Parallel port ATAPI CD-ROM devices + 46 block Parallel port ATAPI CD-ROM devices 0 = /dev/pcd0 First parallel port ATAPI CD-ROM 1 = /dev/pcd1 Second parallel port ATAPI CD-ROM 2 = /dev/pcd2 Third parallel port ATAPI CD-ROM 3 = /dev/pcd3 Fourth parallel port ATAPI CD-ROM - 47 char Comtrol Rocketport serial card - alternate devices + 47 char Comtrol Rocketport serial card - alternate devices 0 = /dev/cur0 Callout device for ttyR0 1 = /dev/cur1 Callout device for ttyR1 ... - 47 block Parallel port ATAPI disk devices + 47 block Parallel port ATAPI disk devices 0 = /dev/pf0 First parallel port ATAPI disk 1 = /dev/pf1 Second parallel port ATAPI disk 2 = /dev/pf2 Third parallel port ATAPI disk @@ -967,11 +972,11 @@ Your cooperation is appreciated. This driver is intended for floppy disks and similar devices and hence does not support partitioning. - 48 char SDL RISCom serial card + 48 char SDL RISCom serial card 0 = /dev/ttyL0 First RISCom port 1 = /dev/ttyL1 Second RISCom port ... - 48 block Mylex DAC960 PCI RAID controller; first controller + 48 block Mylex DAC960 PCI RAID controller; first controller 0 = /dev/rd/c0d0 First disk, whole disk 8 = /dev/rd/c0d1 Second disk, whole disk ... @@ -983,11 +988,11 @@ Your cooperation is appreciated. ... 7 = /dev/rd/c?d?p7 Seventh partition - 49 char SDL RISCom serial card - alternate devices + 49 char SDL RISCom serial card - alternate devices 0 = /dev/cul0 Callout device for ttyL0 1 = /dev/cul1 Callout device for ttyL1 ... - 49 block Mylex DAC960 PCI RAID controller; second controller + 49 block Mylex DAC960 PCI RAID controller; second controller 0 = /dev/rd/c1d0 First disk, whole disk 8 = /dev/rd/c1d1 Second disk, whole disk ... @@ -995,19 +1000,19 @@ Your cooperation is appreciated. Partitions are handled as for major 48. - 50 char Reserved for GLINT + 50 char Reserved for GLINT - 50 block Mylex DAC960 PCI RAID controller; third controller + 50 block Mylex DAC960 PCI RAID controller; third controller 0 = /dev/rd/c2d0 First disk, whole disk 8 = /dev/rd/c2d1 Second disk, whole disk ... 248 = /dev/rd/c2d31 32nd disk, whole disk - 51 char Baycom radio modem OR Radio Tech BIM-XXX-RS232 radio modem + 51 char Baycom radio modem OR Radio Tech BIM-XXX-RS232 radio modem 0 = /dev/bc0 First Baycom radio modem 1 = /dev/bc1 Second Baycom radio modem ... - 51 block Mylex DAC960 PCI RAID controller; fourth controller + 51 block Mylex DAC960 PCI RAID controller; fourth controller 0 = /dev/rd/c3d0 First disk, whole disk 8 = /dev/rd/c3d1 Second disk, whole disk ... @@ -1015,13 +1020,13 @@ Your cooperation is appreciated. Partitions are handled as for major 48. - 52 char Spellcaster DataComm/BRI ISDN card + 52 char Spellcaster DataComm/BRI ISDN card 0 = /dev/dcbri0 First DataComm card 1 = /dev/dcbri1 Second DataComm card 2 = /dev/dcbri2 Third DataComm card 3 = /dev/dcbri3 Fourth DataComm card - 52 block Mylex DAC960 PCI RAID controller; fifth controller + 52 block Mylex DAC960 PCI RAID controller; fifth controller 0 = /dev/rd/c4d0 First disk, whole disk 8 = /dev/rd/c4d1 Second disk, whole disk ... @@ -1029,7 +1034,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. - 53 char BDM interface for remote debugging MC683xx microcontrollers + 53 char BDM interface for remote debugging MC683xx microcontrollers 0 = /dev/pd_bdm0 PD BDM interface on lp0 1 = /dev/pd_bdm1 PD BDM interface on lp1 2 = /dev/pd_bdm2 PD BDM interface on lp2 @@ -1043,7 +1048,7 @@ Your cooperation is appreciated. Domain Interface and ICD is the commercial interface by P&E. - 53 block Mylex DAC960 PCI RAID controller; sixth controller + 53 block Mylex DAC960 PCI RAID controller; sixth controller 0 = /dev/rd/c5d0 First disk, whole disk 8 = /dev/rd/c5d1 Second disk, whole disk ... @@ -1051,7 +1056,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. - 54 char Electrocardiognosis Holter serial card + 54 char Electrocardiognosis Holter serial card 0 = /dev/holter0 First Holter port 1 = /dev/holter1 Second Holter port 2 = /dev/holter2 Third Holter port @@ -1060,7 +1065,7 @@ Your cooperation is appreciated. <mseritan@ottonel.pub.ro> to transfer data from Holter 24-hour heart monitoring equipment. - 54 block Mylex DAC960 PCI RAID controller; seventh controller + 54 block Mylex DAC960 PCI RAID controller; seventh controller 0 = /dev/rd/c6d0 First disk, whole disk 8 = /dev/rd/c6d1 Second disk, whole disk ... @@ -1068,10 +1073,10 @@ Your cooperation is appreciated. Partitions are handled as for major 48. - 55 char DSP56001 digital signal processor + 55 char DSP56001 digital signal processor 0 = /dev/dsp56k First DSP56001 - 55 block Mylex DAC960 PCI RAID controller; eighth controller + 55 block Mylex DAC960 PCI RAID controller; eighth controller 0 = /dev/rd/c7d0 First disk, whole disk 8 = /dev/rd/c7d1 Second disk, whole disk ... @@ -1079,42 +1084,42 @@ Your cooperation is appreciated. Partitions are handled as for major 48. - 56 char Apple Desktop Bus + 56 char Apple Desktop Bus 0 = /dev/adb ADB bus control Additional devices will be added to this number, all starting with /dev/adb. - 56 block Fifth IDE hard disk/CD-ROM interface + 56 block Fifth IDE hard disk/CD-ROM interface 0 = /dev/hdi Master: whole disk (or CD-ROM) 64 = /dev/hdj Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 57 char Hayes ESP serial card + 57 char Hayes ESP serial card 0 = /dev/ttyP0 First ESP port 1 = /dev/ttyP1 Second ESP port ... - 57 block Sixth IDE hard disk/CD-ROM interface + 57 block Sixth IDE hard disk/CD-ROM interface 0 = /dev/hdk Master: whole disk (or CD-ROM) 64 = /dev/hdl Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 58 char Hayes ESP serial card - alternate devices + 58 char Hayes ESP serial card - alternate devices 0 = /dev/cup0 Callout device for ttyP0 1 = /dev/cup1 Callout device for ttyP1 ... - 58 block Reserved for logical volume manager + 58 block Reserved for logical volume manager - 59 char sf firewall package + 59 char sf firewall package 0 = /dev/firewall Communication with sf kernel module - 59 block Generic PDA filesystem device + 59 block Generic PDA filesystem device 0 = /dev/pda0 First PDA device 1 = /dev/pda1 Second PDA device ... @@ -1127,17 +1132,17 @@ Your cooperation is appreciated. NAMING CONFLICT -- PROPOSED REVISED NAME /dev/rpda0 etc - 60-63 char LOCAL/EXPERIMENTAL USE + 60-63 char LOCAL/EXPERIMENTAL USE - 60-63 block LOCAL/EXPERIMENTAL USE + 60-63 block LOCAL/EXPERIMENTAL USE Allocated for local/experimental use. For devices not assigned official numbers, these ranges should be used in order to avoid conflicting with future assignments. - 64 char ENskip kernel encryption package + 64 char ENskip kernel encryption package 0 = /dev/enskip Communication with ENskip kernel module - 64 block Scramdisk/DriveCrypt encrypted devices + 64 block Scramdisk/DriveCrypt encrypted devices 0 = /dev/scramdisk/master Master node for ioctls 1 = /dev/scramdisk/1 First encrypted device 2 = /dev/scramdisk/2 Second encrypted device @@ -1152,7 +1157,7 @@ Your cooperation is appreciated. Requested by: andy@scramdisklinux.org - 65 char Sundance "plink" Transputer boards (obsolete, unused) + 65 char Sundance "plink" Transputer boards (obsolete, unused) 0 = /dev/plink0 First plink device 1 = /dev/plink1 Second plink device 2 = /dev/plink2 Third plink device @@ -1173,7 +1178,7 @@ Your cooperation is appreciated. This is a commercial driver; contact James Howes <jth@prosig.demon.co.uk> for information. - 65 block SCSI disk devices (16-31) + 65 block SCSI disk devices (16-31) 0 = /dev/sdq 17th SCSI disk whole disk 16 = /dev/sdr 18th SCSI disk whole disk 32 = /dev/sds 19th SCSI disk whole disk @@ -1184,12 +1189,12 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 66 char YARC PowerPC PCI coprocessor card + 66 char YARC PowerPC PCI coprocessor card 0 = /dev/yppcpci0 First YARC card 1 = /dev/yppcpci1 Second YARC card ... - 66 block SCSI disk devices (32-47) + 66 block SCSI disk devices (32-47) 0 = /dev/sdag 33th SCSI disk whole disk 16 = /dev/sdah 34th SCSI disk whole disk 32 = /dev/sdai 35th SCSI disk whole disk @@ -1200,12 +1205,12 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 67 char Coda network file system + 67 char Coda network file system 0 = /dev/cfs0 Coda cache manager See http://www.coda.cs.cmu.edu for information about Coda. - 67 block SCSI disk devices (48-63) + 67 block SCSI disk devices (48-63) 0 = /dev/sdaw 49th SCSI disk whole disk 16 = /dev/sdax 50th SCSI disk whole disk 32 = /dev/sday 51st SCSI disk whole disk @@ -1216,7 +1221,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 68 char CAPI 2.0 interface + 68 char CAPI 2.0 interface 0 = /dev/capi20 Control device 1 = /dev/capi20.00 First CAPI 2.0 application 2 = /dev/capi20.01 Second CAPI 2.0 application @@ -1226,7 +1231,7 @@ Your cooperation is appreciated. ISDN CAPI 2.0 driver for use with CAPI 2.0 applications; currently supports the AVM B1 card. - 68 block SCSI disk devices (64-79) + 68 block SCSI disk devices (64-79) 0 = /dev/sdbm 65th SCSI disk whole disk 16 = /dev/sdbn 66th SCSI disk whole disk 32 = /dev/sdbo 67th SCSI disk whole disk @@ -1237,10 +1242,10 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 69 char MA16 numeric accelerator card + 69 char MA16 numeric accelerator card 0 = /dev/ma16 Board memory access - 69 block SCSI disk devices (80-95) + 69 block SCSI disk devices (80-95) 0 = /dev/sdcc 81st SCSI disk whole disk 16 = /dev/sdcd 82nd SCSI disk whole disk 32 = /dev/sdce 83th SCSI disk whole disk @@ -1251,7 +1256,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 70 char SpellCaster Protocol Services Interface + 70 char SpellCaster Protocol Services Interface 0 = /dev/apscfg Configuration interface 1 = /dev/apsauth Authentication interface 2 = /dev/apslog Logging interface @@ -1260,7 +1265,7 @@ Your cooperation is appreciated. 65 = /dev/apsasync Async command interface 128 = /dev/apsmon Monitor interface - 70 block SCSI disk devices (96-111) + 70 block SCSI disk devices (96-111) 0 = /dev/sdcs 97th SCSI disk whole disk 16 = /dev/sdct 98th SCSI disk whole disk 32 = /dev/sdcu 99th SCSI disk whole disk @@ -1271,7 +1276,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 71 char Computone IntelliPort II serial card + 71 char Computone IntelliPort II serial card 0 = /dev/ttyF0 IntelliPort II board 0, port 0 1 = /dev/ttyF1 IntelliPort II board 0, port 1 ... @@ -1289,7 +1294,7 @@ Your cooperation is appreciated. ... 255 = /dev/ttyF255 IntelliPort II board 3, port 63 - 71 block SCSI disk devices (112-127) + 71 block SCSI disk devices (112-127) 0 = /dev/sddi 113th SCSI disk whole disk 16 = /dev/sddj 114th SCSI disk whole disk 32 = /dev/sddk 115th SCSI disk whole disk @@ -1300,7 +1305,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 72 char Computone IntelliPort II serial card - alternate devices + 72 char Computone IntelliPort II serial card - alternate devices 0 = /dev/cuf0 Callout device for ttyF0 1 = /dev/cuf1 Callout device for ttyF1 ... @@ -1318,7 +1323,7 @@ Your cooperation is appreciated. ... 255 = /dev/cuf255 Callout device for ttyF255 - 72 block Compaq Intelligent Drive Array, first controller + 72 block Compaq Intelligent Drive Array, first controller 0 = /dev/ida/c0d0 First logical drive whole disk 16 = /dev/ida/c0d1 Second logical drive whole disk ... @@ -1328,7 +1333,7 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. - 73 char Computone IntelliPort II serial card - control devices + 73 char Computone IntelliPort II serial card - control devices 0 = /dev/ip2ipl0 Loadware device for board 0 1 = /dev/ip2stat0 Status device for board 0 4 = /dev/ip2ipl1 Loadware device for board 1 @@ -1338,7 +1343,7 @@ Your cooperation is appreciated. 12 = /dev/ip2ipl3 Loadware device for board 3 13 = /dev/ip2stat3 Status device for board 3 - 73 block Compaq Intelligent Drive Array, second controller + 73 block Compaq Intelligent Drive Array, second controller 0 = /dev/ida/c1d0 First logical drive whole disk 16 = /dev/ida/c1d1 Second logical drive whole disk ... @@ -1348,7 +1353,7 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. - 74 char SCI bridge + 74 char SCI bridge 0 = /dev/SCI/0 SCI device 0 1 = /dev/SCI/1 SCI device 1 ... @@ -1356,7 +1361,7 @@ Your cooperation is appreciated. Currently for Dolphin Interconnect Solutions' PCI-SCI bridge. - 74 block Compaq Intelligent Drive Array, third controller + 74 block Compaq Intelligent Drive Array, third controller 0 = /dev/ida/c2d0 First logical drive whole disk 16 = /dev/ida/c2d1 Second logical drive whole disk ... @@ -1366,14 +1371,14 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. - 75 char Specialix IO8+ serial card + 75 char Specialix IO8+ serial card 0 = /dev/ttyW0 First IO8+ port, first card 1 = /dev/ttyW1 Second IO8+ port, first card ... 8 = /dev/ttyW8 First IO8+ port, second card ... - 75 block Compaq Intelligent Drive Array, fourth controller + 75 block Compaq Intelligent Drive Array, fourth controller 0 = /dev/ida/c3d0 First logical drive whole disk 16 = /dev/ida/c3d1 Second logical drive whole disk ... @@ -1383,14 +1388,14 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. - 76 char Specialix IO8+ serial card - alternate devices + 76 char Specialix IO8+ serial card - alternate devices 0 = /dev/cuw0 Callout device for ttyW0 1 = /dev/cuw1 Callout device for ttyW1 ... 8 = /dev/cuw8 Callout device for ttyW8 ... - 76 block Compaq Intelligent Drive Array, fifth controller + 76 block Compaq Intelligent Drive Array, fifth controller 0 = /dev/ida/c4d0 First logical drive whole disk 16 = /dev/ida/c4d1 Second logical drive whole disk ... @@ -1401,10 +1406,10 @@ Your cooperation is appreciated. partitions is 15. - 77 char ComScire Quantum Noise Generator + 77 char ComScire Quantum Noise Generator 0 = /dev/qng ComScire Quantum Noise Generator - 77 block Compaq Intelligent Drive Array, sixth controller + 77 block Compaq Intelligent Drive Array, sixth controller 0 = /dev/ida/c5d0 First logical drive whole disk 16 = /dev/ida/c5d1 Second logical drive whole disk ... @@ -1414,12 +1419,12 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. - 78 char PAM Software's multimodem boards + 78 char PAM Software's multimodem boards 0 = /dev/ttyM0 First PAM modem 1 = /dev/ttyM1 Second PAM modem ... - 78 block Compaq Intelligent Drive Array, seventh controller + 78 block Compaq Intelligent Drive Array, seventh controller 0 = /dev/ida/c6d0 First logical drive whole disk 16 = /dev/ida/c6d1 Second logical drive whole disk ... @@ -1429,12 +1434,12 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. - 79 char PAM Software's multimodem boards - alternate devices + 79 char PAM Software's multimodem boards - alternate devices 0 = /dev/cum0 Callout device for ttyM0 1 = /dev/cum1 Callout device for ttyM1 ... - 79 block Compaq Intelligent Drive Array, eighth controller + 79 block Compaq Intelligent Drive Array, eighth controller 0 = /dev/ida/c7d0 First logical drive whole disk 16 = /dev/ida/c7d1 Second logical drive whole disk ... @@ -1444,10 +1449,10 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. - 80 char Photometrics AT200 CCD camera + 80 char Photometrics AT200 CCD camera 0 = /dev/at200 Photometrics AT200 CCD camera - 80 block I2O hard disk + 80 block I2O hard disk 0 = /dev/i2o/hda First I2O hard disk, whole disk 16 = /dev/i2o/hdb Second I2O hard disk, whole disk ... @@ -1457,7 +1462,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 81 char video4linux + 81 char video4linux 0 = /dev/video0 Video capture/overlay device ... 63 = /dev/video63 Video capture/overlay device @@ -1475,7 +1480,7 @@ Your cooperation is appreciated. CONFIG_VIDEO_FIXED_MINOR_RANGES (default n) configuration option is set. - 81 block I2O hard disk + 81 block I2O hard disk 0 = /dev/i2o/hdq 17th I2O hard disk, whole disk 16 = /dev/i2o/hdr 18th I2O hard disk, whole disk ... @@ -1485,7 +1490,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 82 char WiNRADiO communications receiver card + 82 char WiNRADiO communications receiver card 0 = /dev/winradio0 First WiNRADiO card 1 = /dev/winradio1 Second WiNRADiO card ... @@ -1493,7 +1498,7 @@ Your cooperation is appreciated. The driver and documentation may be obtained from http://www.winradio.com/ - 82 block I2O hard disk + 82 block I2O hard disk 0 = /dev/i2o/hdag 33rd I2O hard disk, whole disk 16 = /dev/i2o/hdah 34th I2O hard disk, whole disk ... @@ -1503,14 +1508,14 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 83 char Matrox mga_vid video driver - 0 = /dev/mga_vid0 1st video card + 83 char Matrox mga_vid video driver + 0 = /dev/mga_vid0 1st video card 1 = /dev/mga_vid1 2nd video card 2 = /dev/mga_vid2 3rd video card ... - 15 = /dev/mga_vid15 16th video card + 15 = /dev/mga_vid15 16th video card - 83 block I2O hard disk + 83 block I2O hard disk 0 = /dev/i2o/hdaw 49th I2O hard disk, whole disk 16 = /dev/i2o/hdax 50th I2O hard disk, whole disk ... @@ -1520,11 +1525,11 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 84 char Ikon 1011[57] Versatec Greensheet Interface + 84 char Ikon 1011[57] Versatec Greensheet Interface 0 = /dev/ihcp0 First Greensheet port 1 = /dev/ihcp1 Second Greensheet port - 84 block I2O hard disk + 84 block I2O hard disk 0 = /dev/i2o/hdbm 65th I2O hard disk, whole disk 16 = /dev/i2o/hdbn 66th I2O hard disk, whole disk ... @@ -1534,13 +1539,13 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 85 char Linux/SGI shared memory input queue + 85 char Linux/SGI shared memory input queue 0 = /dev/shmiq Master shared input queue 1 = /dev/qcntl0 First device pushed 2 = /dev/qcntl1 Second device pushed ... - 85 block I2O hard disk + 85 block I2O hard disk 0 = /dev/i2o/hdcc 81st I2O hard disk, whole disk 16 = /dev/i2o/hdcd 82nd I2O hard disk, whole disk ... @@ -1550,12 +1555,12 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 86 char SCSI media changer + 86 char SCSI media changer 0 = /dev/sch0 First SCSI media changer 1 = /dev/sch1 Second SCSI media changer ... - 86 block I2O hard disk + 86 block I2O hard disk 0 = /dev/i2o/hdcs 97th I2O hard disk, whole disk 16 = /dev/i2o/hdct 98th I2O hard disk, whole disk ... @@ -1565,12 +1570,12 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 87 char Sony Control-A1 stereo control bus + 87 char Sony Control-A1 stereo control bus 0 = /dev/controla0 First device on chain 1 = /dev/controla1 Second device on chain ... - 87 block I2O hard disk + 87 block I2O hard disk 0 = /dev/i2o/hddi 113rd I2O hard disk, whole disk 16 = /dev/i2o/hddj 114th I2O hard disk, whole disk ... @@ -1580,59 +1585,59 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 88 char COMX synchronous serial card + 88 char COMX synchronous serial card 0 = /dev/comx0 COMX channel 0 1 = /dev/comx1 COMX channel 1 ... - 88 block Seventh IDE hard disk/CD-ROM interface + 88 block Seventh IDE hard disk/CD-ROM interface 0 = /dev/hdm Master: whole disk (or CD-ROM) 64 = /dev/hdn Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 89 char I2C bus interface + 89 char I2C bus interface 0 = /dev/i2c-0 First I2C adapter 1 = /dev/i2c-1 Second I2C adapter ... - 89 block Eighth IDE hard disk/CD-ROM interface + 89 block Eighth IDE hard disk/CD-ROM interface 0 = /dev/hdo Master: whole disk (or CD-ROM) 64 = /dev/hdp Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 90 char Memory Technology Device (RAM, ROM, Flash) + 90 char Memory Technology Device (RAM, ROM, Flash) 0 = /dev/mtd0 First MTD (rw) 1 = /dev/mtdr0 First MTD (ro) ... 30 = /dev/mtd15 16th MTD (rw) 31 = /dev/mtdr15 16th MTD (ro) - 90 block Ninth IDE hard disk/CD-ROM interface + 90 block Ninth IDE hard disk/CD-ROM interface 0 = /dev/hdq Master: whole disk (or CD-ROM) 64 = /dev/hdr Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 91 char CAN-Bus devices + 91 char CAN-Bus devices 0 = /dev/can0 First CAN-Bus controller 1 = /dev/can1 Second CAN-Bus controller ... - 91 block Tenth IDE hard disk/CD-ROM interface + 91 block Tenth IDE hard disk/CD-ROM interface 0 = /dev/hds Master: whole disk (or CD-ROM) 64 = /dev/hdt Slave: whole disk (or CD-ROM) Partitions are handled the same way as for the first interface (see major number 3). - 92 char Reserved for ith Kommunikationstechnik MIC ISDN card + 92 char Reserved for ith Kommunikationstechnik MIC ISDN card - 92 block PPDD encrypted disk driver + 92 block PPDD encrypted disk driver 0 = /dev/ppdd0 First encrypted disk 1 = /dev/ppdd1 Second encrypted disk ... @@ -1641,35 +1646,35 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 93 char + 93 char - 93 block NAND Flash Translation Layer filesystem + 93 block NAND Flash Translation Layer filesystem 0 = /dev/nftla First NFTL layer 16 = /dev/nftlb Second NFTL layer ... 240 = /dev/nftlp 16th NTFL layer - 94 char + 94 char - 94 block IBM S/390 DASD block storage - 0 = /dev/dasda First DASD device, major - 1 = /dev/dasda1 First DASD device, block 1 - 2 = /dev/dasda2 First DASD device, block 2 - 3 = /dev/dasda3 First DASD device, block 3 - 4 = /dev/dasdb Second DASD device, major - 5 = /dev/dasdb1 Second DASD device, block 1 - 6 = /dev/dasdb2 Second DASD device, block 2 - 7 = /dev/dasdb3 Second DASD device, block 3 + 94 block IBM S/390 DASD block storage + 0 = /dev/dasda First DASD device, major + 1 = /dev/dasda1 First DASD device, block 1 + 2 = /dev/dasda2 First DASD device, block 2 + 3 = /dev/dasda3 First DASD device, block 3 + 4 = /dev/dasdb Second DASD device, major + 5 = /dev/dasdb1 Second DASD device, block 1 + 6 = /dev/dasdb2 Second DASD device, block 2 + 7 = /dev/dasdb3 Second DASD device, block 3 ... - 95 char IP filter + 95 char IP filter 0 = /dev/ipl Filter control device/log file 1 = /dev/ipnat NAT control device/log file 2 = /dev/ipstate State information log file 3 = /dev/ipauth Authentication control device/log file ... - 96 char Parallel port ATAPI tape devices + 96 char Parallel port ATAPI tape devices 0 = /dev/pt0 First parallel port ATAPI tape 1 = /dev/pt1 Second parallel port ATAPI tape ... @@ -1677,13 +1682,13 @@ Your cooperation is appreciated. 129 = /dev/npt1 Second p.p. ATAPI tape, no rewind ... - 96 block Inverse NAND Flash Translation Layer + 96 block Inverse NAND Flash Translation Layer 0 = /dev/inftla First INFTL layer 16 = /dev/inftlb Second INFTL layer ... 240 = /dev/inftlp 16th INTFL layer - 97 char Parallel port generic ATAPI interface + 97 char Parallel port generic ATAPI interface 0 = /dev/pg0 First parallel port ATAPI device 1 = /dev/pg1 Second parallel port ATAPI device 2 = /dev/pg2 Third parallel port ATAPI device @@ -1692,14 +1697,14 @@ Your cooperation is appreciated. These devices support the same API as the generic SCSI devices. - 98 char Control and Measurement Device (comedi) + 98 char Control and Measurement Device (comedi) 0 = /dev/comedi0 First comedi device 1 = /dev/comedi1 Second comedi device ... See http://stm.lbl.gov/comedi. - 98 block User-mode virtual block device + 98 block User-mode virtual block device 0 = /dev/ubda First user-mode block device 16 = /dev/udbb Second user-mode block device ... @@ -1710,26 +1715,26 @@ Your cooperation is appreciated. This device is used by the user-mode virtual kernel port. - 99 char Raw parallel ports + 99 char Raw parallel ports 0 = /dev/parport0 First parallel port 1 = /dev/parport1 Second parallel port ... - 99 block JavaStation flash disk + 99 block JavaStation flash disk 0 = /dev/jsfd JavaStation flash disk -100 char Telephony for Linux + 100 char Telephony for Linux 0 = /dev/phone0 First telephony device 1 = /dev/phone1 Second telephony device ... -101 char Motorola DSP 56xxx board + 101 char Motorola DSP 56xxx board 0 = /dev/mdspstat Status information 1 = /dev/mdsp1 First DSP board I/O controls ... 16 = /dev/mdsp16 16th DSP board I/O controls -101 block AMI HyperDisk RAID controller + 101 block AMI HyperDisk RAID controller 0 = /dev/amiraid/ar0 First array whole disk 16 = /dev/amiraid/ar1 Second array whole disk ... @@ -1742,9 +1747,9 @@ Your cooperation is appreciated. ... 15 = /dev/amiraid/ar?p15 15th partition -102 char + 102 char -102 block Compressed block device + 102 block Compressed block device 0 = /dev/cbd/a First compressed block device, whole device 16 = /dev/cbd/b Second compressed block device, whole device ... @@ -1754,7 +1759,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. -103 char Arla network file system + 103 char Arla network file system 0 = /dev/nnpfs0 First NNPFS device 1 = /dev/nnpfs1 Second NNPFS device @@ -1765,12 +1770,12 @@ Your cooperation is appreciated. write to <arla-drinkers@stacken.kth.se> or see http://www.stacken.kth.se/project/arla/ -103 block Audit device + 103 block Audit device 0 = /dev/audit Audit device -104 char Flash BIOS support + 104 char Flash BIOS support -104 block Compaq Next Generation Drive Array, first controller + 104 block Compaq Next Generation Drive Array, first controller 0 = /dev/cciss/c0d0 First logical drive, whole disk 16 = /dev/cciss/c0d1 Second logical drive, whole disk ... @@ -1780,12 +1785,12 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -105 char Comtrol VS-1000 serial controller + 105 char Comtrol VS-1000 serial controller 0 = /dev/ttyV0 First VS-1000 port 1 = /dev/ttyV1 Second VS-1000 port ... -105 block Compaq Next Generation Drive Array, second controller + 105 block Compaq Next Generation Drive Array, second controller 0 = /dev/cciss/c1d0 First logical drive, whole disk 16 = /dev/cciss/c1d1 Second logical drive, whole disk ... @@ -1795,12 +1800,12 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -106 char Comtrol VS-1000 serial controller - alternate devices + 106 char Comtrol VS-1000 serial controller - alternate devices 0 = /dev/cuv0 First VS-1000 port 1 = /dev/cuv1 Second VS-1000 port ... -106 block Compaq Next Generation Drive Array, third controller + 106 block Compaq Next Generation Drive Array, third controller 0 = /dev/cciss/c2d0 First logical drive, whole disk 16 = /dev/cciss/c2d1 Second logical drive, whole disk ... @@ -1810,10 +1815,10 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -107 char 3Dfx Voodoo Graphics device + 107 char 3Dfx Voodoo Graphics device 0 = /dev/3dfx Primary 3Dfx graphics device -107 block Compaq Next Generation Drive Array, fourth controller + 107 block Compaq Next Generation Drive Array, fourth controller 0 = /dev/cciss/c3d0 First logical drive, whole disk 16 = /dev/cciss/c3d1 Second logical drive, whole disk ... @@ -1823,10 +1828,10 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -108 char Device independent PPP interface + 108 char Device independent PPP interface 0 = /dev/ppp Device independent PPP interface -108 block Compaq Next Generation Drive Array, fifth controller + 108 block Compaq Next Generation Drive Array, fifth controller 0 = /dev/cciss/c4d0 First logical drive, whole disk 16 = /dev/cciss/c4d1 Second logical drive, whole disk ... @@ -1836,9 +1841,9 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -109 char Reserved for logical volume manager + 109 char Reserved for logical volume manager -109 block Compaq Next Generation Drive Array, sixth controller + 109 block Compaq Next Generation Drive Array, sixth controller 0 = /dev/cciss/c5d0 First logical drive, whole disk 16 = /dev/cciss/c5d1 Second logical drive, whole disk ... @@ -1848,12 +1853,12 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -110 char miroMEDIA Surround board + 110 char miroMEDIA Surround board 0 = /dev/srnd0 First miroMEDIA Surround board 1 = /dev/srnd1 Second miroMEDIA Surround board ... -110 block Compaq Next Generation Drive Array, seventh controller + 110 block Compaq Next Generation Drive Array, seventh controller 0 = /dev/cciss/c6d0 First logical drive, whole disk 16 = /dev/cciss/c6d1 Second logical drive, whole disk ... @@ -1863,9 +1868,9 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -111 char + 111 char -111 block Compaq Next Generation Drive Array, eighth controller + 111 block Compaq Next Generation Drive Array, eighth controller 0 = /dev/cciss/c7d0 First logical drive, whole disk 16 = /dev/cciss/c7d1 Second logical drive, whole disk ... @@ -1875,7 +1880,7 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -112 char ISI serial card + 112 char ISI serial card 0 = /dev/ttyM0 First ISI port 1 = /dev/ttyM1 Second ISI port ... @@ -1883,7 +1888,7 @@ Your cooperation is appreciated. There is currently a device-naming conflict between these and PAM multimodems (major 78). -112 block IBM iSeries virtual disk + 112 block IBM iSeries virtual disk 0 = /dev/iseries/vda First virtual disk, whole disk 8 = /dev/iseries/vdb Second virtual disk, whole disk ... @@ -1896,17 +1901,17 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 7. -113 char ISI serial card - alternate devices + 113 char ISI serial card - alternate devices 0 = /dev/cum0 Callout device for ttyM0 1 = /dev/cum1 Callout device for ttyM1 ... -113 block IBM iSeries virtual CD-ROM + 113 block IBM iSeries virtual CD-ROM 0 = /dev/iseries/vcda First virtual CD-ROM 1 = /dev/iseries/vcdb Second virtual CD-ROM ... -114 char Picture Elements ISE board + 114 char Picture Elements ISE board 0 = /dev/ise0 First ISE board 1 = /dev/ise1 Second ISE board ... @@ -1919,24 +1924,24 @@ Your cooperation is appreciated. I/O access to the board, the /dev/isex0 nodes command nodes used to control the board. -114 block IDE BIOS powered software RAID interfaces such as the - Promise Fastrak + 114 block IDE BIOS powered software RAID interfaces such as the + Promise Fastrak - 0 = /dev/ataraid/d0 - 1 = /dev/ataraid/d0p1 - 2 = /dev/ataraid/d0p2 - ... - 16 = /dev/ataraid/d1 - 17 = /dev/ataraid/d1p1 - 18 = /dev/ataraid/d1p2 - ... - 255 = /dev/ataraid/d15p15 + 0 = /dev/ataraid/d0 + 1 = /dev/ataraid/d0p1 + 2 = /dev/ataraid/d0p2 + ... + 16 = /dev/ataraid/d1 + 17 = /dev/ataraid/d1p1 + 18 = /dev/ataraid/d1p2 + ... + 255 = /dev/ataraid/d15p15 Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -115 char TI link cable devices (115 was formerly the console driver speaker) + 115 char TI link cable devices (115 was formerly the console driver speaker) 0 = /dev/tipar0 Parallel cable on first parallel port ... 7 = /dev/tipar7 Parallel cable on seventh parallel port @@ -1949,28 +1954,28 @@ Your cooperation is appreciated. ... 47 = /dev/tiusb31 32nd USB cable -115 block NetWare (NWFS) Devices (0-255) + 115 block NetWare (NWFS) Devices (0-255) - The NWFS (NetWare) devices are used to present a - collection of NetWare Mirror Groups or NetWare - Partitions as a logical storage segment for - use in mounting NetWare volumes. A maximum of - 256 NetWare volumes can be supported in a single - machine. + The NWFS (NetWare) devices are used to present a + collection of NetWare Mirror Groups or NetWare + Partitions as a logical storage segment for + use in mounting NetWare volumes. A maximum of + 256 NetWare volumes can be supported in a single + machine. - http://cgfa.telepac.pt/ftp2/kernel.org/linux/kernel/people/jmerkey/nwfs/ + http://cgfa.telepac.pt/ftp2/kernel.org/linux/kernel/people/jmerkey/nwfs/ - 0 = /dev/nwfs/v0 First NetWare (NWFS) Logical Volume - 1 = /dev/nwfs/v1 Second NetWare (NWFS) Logical Volume - 2 = /dev/nwfs/v2 Third NetWare (NWFS) Logical Volume - ... - 255 = /dev/nwfs/v255 Last NetWare (NWFS) Logical Volume + 0 = /dev/nwfs/v0 First NetWare (NWFS) Logical Volume + 1 = /dev/nwfs/v1 Second NetWare (NWFS) Logical Volume + 2 = /dev/nwfs/v2 Third NetWare (NWFS) Logical Volume + ... + 255 = /dev/nwfs/v255 Last NetWare (NWFS) Logical Volume -116 char Advanced Linux Sound Driver (ALSA) + 116 char Advanced Linux Sound Driver (ALSA) -116 block MicroMemory battery backed RAM adapter (NVRAM) - Supports 16 boards, 15 partitions each. - Requested by neilb at cse.unsw.edu.au. + 116 block MicroMemory battery backed RAM adapter (NVRAM) + Supports 16 boards, 15 partitions each. + Requested by neilb at cse.unsw.edu.au. 0 = /dev/umem/d0 Whole of first board 1 = /dev/umem/d0p1 First partition of first board @@ -1982,7 +1987,7 @@ Your cooperation is appreciated. ... 255= /dev/umem/d15p15 15th partition of 16th board. -117 char COSA/SRP synchronous serial card + 117 char COSA/SRP synchronous serial card 0 = /dev/cosa0c0 1st board, 1st channel 1 = /dev/cosa0c1 1st board, 2nd channel ... @@ -1990,147 +1995,147 @@ Your cooperation is appreciated. 17 = /dev/cosa1c1 2nd board, 2nd channel ... -117 block Enterprise Volume Management System (EVMS) + 117 block Enterprise Volume Management System (EVMS) - The EVMS driver uses a layered, plug-in model to provide - unparalleled flexibility and extensibility in managing - storage. This allows for easy expansion or customization - of various levels of volume management. Requested by - Mark Peloquin (peloquin at us.ibm.com). + The EVMS driver uses a layered, plug-in model to provide + unparalleled flexibility and extensibility in managing + storage. This allows for easy expansion or customization + of various levels of volume management. Requested by + Mark Peloquin (peloquin at us.ibm.com). - Note: EVMS populates and manages all the devnodes in - /dev/evms. + Note: EVMS populates and manages all the devnodes in + /dev/evms. - http://sf.net/projects/evms + http://sf.net/projects/evms - 0 = /dev/evms/block_device EVMS block device - 1 = /dev/evms/legacyname1 First EVMS legacy device - 2 = /dev/evms/legacyname2 Second EVMS legacy device - ... - Both ranges can grow (down or up) until they meet. - ... - 254 = /dev/evms/EVMSname2 Second EVMS native device - 255 = /dev/evms/EVMSname1 First EVMS native device + 0 = /dev/evms/block_device EVMS block device + 1 = /dev/evms/legacyname1 First EVMS legacy device + 2 = /dev/evms/legacyname2 Second EVMS legacy device + ... + Both ranges can grow (down or up) until they meet. + ... + 254 = /dev/evms/EVMSname2 Second EVMS native device + 255 = /dev/evms/EVMSname1 First EVMS native device - Note: legacyname(s) are derived from the normal legacy - device names. For example, /dev/hda5 would become - /dev/evms/hda5. + Note: legacyname(s) are derived from the normal legacy + device names. For example, /dev/hda5 would become + /dev/evms/hda5. -118 char IBM Cryptographic Accelerator + 118 char IBM Cryptographic Accelerator 0 = /dev/ica Virtual interface to all IBM Crypto Accelerators 1 = /dev/ica0 IBMCA Device 0 2 = /dev/ica1 IBMCA Device 1 ... -119 char VMware virtual network control + 119 char VMware virtual network control 0 = /dev/vnet0 1st virtual network 1 = /dev/vnet1 2nd virtual network ... -120-127 char LOCAL/EXPERIMENTAL USE + 120-127 char LOCAL/EXPERIMENTAL USE -120-127 block LOCAL/EXPERIMENTAL USE + 120-127 block LOCAL/EXPERIMENTAL USE Allocated for local/experimental use. For devices not assigned official numbers, these ranges should be used in order to avoid conflicting with future assignments. -128-135 char Unix98 PTY masters + 128-135 char Unix98 PTY masters These devices should not have corresponding device nodes; instead they should be accessed through the /dev/ptmx cloning interface. -128 block SCSI disk devices (128-143) - 0 = /dev/sddy 129th SCSI disk whole disk - 16 = /dev/sddz 130th SCSI disk whole disk - 32 = /dev/sdea 131th SCSI disk whole disk - ... - 240 = /dev/sden 144th SCSI disk whole disk + 128 block SCSI disk devices (128-143) + 0 = /dev/sddy 129th SCSI disk whole disk + 16 = /dev/sddz 130th SCSI disk whole disk + 32 = /dev/sdea 131th SCSI disk whole disk + ... + 240 = /dev/sden 144th SCSI disk whole disk Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -129 block SCSI disk devices (144-159) - 0 = /dev/sdeo 145th SCSI disk whole disk - 16 = /dev/sdep 146th SCSI disk whole disk - 32 = /dev/sdeq 147th SCSI disk whole disk - ... - 240 = /dev/sdfd 160th SCSI disk whole disk + 129 block SCSI disk devices (144-159) + 0 = /dev/sdeo 145th SCSI disk whole disk + 16 = /dev/sdep 146th SCSI disk whole disk + 32 = /dev/sdeq 147th SCSI disk whole disk + ... + 240 = /dev/sdfd 160th SCSI disk whole disk Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -130 char (Misc devices) + 130 char (Misc devices) -130 block SCSI disk devices (160-175) - 0 = /dev/sdfe 161st SCSI disk whole disk - 16 = /dev/sdff 162nd SCSI disk whole disk - 32 = /dev/sdfg 163rd SCSI disk whole disk - ... - 240 = /dev/sdft 176th SCSI disk whole disk + 130 block SCSI disk devices (160-175) + 0 = /dev/sdfe 161st SCSI disk whole disk + 16 = /dev/sdff 162nd SCSI disk whole disk + 32 = /dev/sdfg 163rd SCSI disk whole disk + ... + 240 = /dev/sdft 176th SCSI disk whole disk Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -131 block SCSI disk devices (176-191) - 0 = /dev/sdfu 177th SCSI disk whole disk - 16 = /dev/sdfv 178th SCSI disk whole disk - 32 = /dev/sdfw 179th SCSI disk whole disk - ... - 240 = /dev/sdgj 192nd SCSI disk whole disk + 131 block SCSI disk devices (176-191) + 0 = /dev/sdfu 177th SCSI disk whole disk + 16 = /dev/sdfv 178th SCSI disk whole disk + 32 = /dev/sdfw 179th SCSI disk whole disk + ... + 240 = /dev/sdgj 192nd SCSI disk whole disk Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -132 block SCSI disk devices (192-207) - 0 = /dev/sdgk 193rd SCSI disk whole disk - 16 = /dev/sdgl 194th SCSI disk whole disk - 32 = /dev/sdgm 195th SCSI disk whole disk - ... - 240 = /dev/sdgz 208th SCSI disk whole disk + 132 block SCSI disk devices (192-207) + 0 = /dev/sdgk 193rd SCSI disk whole disk + 16 = /dev/sdgl 194th SCSI disk whole disk + 32 = /dev/sdgm 195th SCSI disk whole disk + ... + 240 = /dev/sdgz 208th SCSI disk whole disk Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -133 block SCSI disk devices (208-223) - 0 = /dev/sdha 209th SCSI disk whole disk - 16 = /dev/sdhb 210th SCSI disk whole disk - 32 = /dev/sdhc 211th SCSI disk whole disk - ... - 240 = /dev/sdhp 224th SCSI disk whole disk + 133 block SCSI disk devices (208-223) + 0 = /dev/sdha 209th SCSI disk whole disk + 16 = /dev/sdhb 210th SCSI disk whole disk + 32 = /dev/sdhc 211th SCSI disk whole disk + ... + 240 = /dev/sdhp 224th SCSI disk whole disk Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -134 block SCSI disk devices (224-239) - 0 = /dev/sdhq 225th SCSI disk whole disk - 16 = /dev/sdhr 226th SCSI disk whole disk - 32 = /dev/sdhs 227th SCSI disk whole disk - ... - 240 = /dev/sdif 240th SCSI disk whole disk + 134 block SCSI disk devices (224-239) + 0 = /dev/sdhq 225th SCSI disk whole disk + 16 = /dev/sdhr 226th SCSI disk whole disk + 32 = /dev/sdhs 227th SCSI disk whole disk + ... + 240 = /dev/sdif 240th SCSI disk whole disk Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -135 block SCSI disk devices (240-255) - 0 = /dev/sdig 241st SCSI disk whole disk - 16 = /dev/sdih 242nd SCSI disk whole disk - 32 = /dev/sdih 243rd SCSI disk whole disk - ... - 240 = /dev/sdiv 256th SCSI disk whole disk + 135 block SCSI disk devices (240-255) + 0 = /dev/sdig 241st SCSI disk whole disk + 16 = /dev/sdih 242nd SCSI disk whole disk + 32 = /dev/sdih 243rd SCSI disk whole disk + ... + 240 = /dev/sdiv 256th SCSI disk whole disk Partitions are handled in the same way as for IDE disks (see major number 3) except that the limit on partitions is 15. -136-143 char Unix98 PTY slaves + 136-143 char Unix98 PTY slaves 0 = /dev/pts/0 First Unix98 pseudo-TTY 1 = /dev/pts/1 Second Unix98 pseudo-TTY ... @@ -2142,7 +2147,7 @@ Your cooperation is appreciated. *most* distributions the appropriate options are "mode=0620,gid=<gid of the "tty" group>".) -136 block Mylex DAC960 PCI RAID controller; ninth controller + 136 block Mylex DAC960 PCI RAID controller; ninth controller 0 = /dev/rd/c8d0 First disk, whole disk 8 = /dev/rd/c8d1 Second disk, whole disk ... @@ -2150,7 +2155,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. -137 block Mylex DAC960 PCI RAID controller; tenth controller + 137 block Mylex DAC960 PCI RAID controller; tenth controller 0 = /dev/rd/c9d0 First disk, whole disk 8 = /dev/rd/c9d1 Second disk, whole disk ... @@ -2158,7 +2163,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. -138 block Mylex DAC960 PCI RAID controller; eleventh controller + 138 block Mylex DAC960 PCI RAID controller; eleventh controller 0 = /dev/rd/c10d0 First disk, whole disk 8 = /dev/rd/c10d1 Second disk, whole disk ... @@ -2166,7 +2171,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. -139 block Mylex DAC960 PCI RAID controller; twelfth controller + 139 block Mylex DAC960 PCI RAID controller; twelfth controller 0 = /dev/rd/c11d0 First disk, whole disk 8 = /dev/rd/c11d1 Second disk, whole disk ... @@ -2174,7 +2179,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. -140 block Mylex DAC960 PCI RAID controller; thirteenth controller + 140 block Mylex DAC960 PCI RAID controller; thirteenth controller 0 = /dev/rd/c12d0 First disk, whole disk 8 = /dev/rd/c12d1 Second disk, whole disk ... @@ -2182,7 +2187,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. -141 block Mylex DAC960 PCI RAID controller; fourteenth controller + 141 block Mylex DAC960 PCI RAID controller; fourteenth controller 0 = /dev/rd/c13d0 First disk, whole disk 8 = /dev/rd/c13d1 Second disk, whole disk ... @@ -2190,7 +2195,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. -142 block Mylex DAC960 PCI RAID controller; fifteenth controller + 142 block Mylex DAC960 PCI RAID controller; fifteenth controller 0 = /dev/rd/c14d0 First disk, whole disk 8 = /dev/rd/c14d1 Second disk, whole disk ... @@ -2198,7 +2203,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. -143 block Mylex DAC960 PCI RAID controller; sixteenth controller + 143 block Mylex DAC960 PCI RAID controller; sixteenth controller 0 = /dev/rd/c15d0 First disk, whole disk 8 = /dev/rd/c15d1 Second disk, whole disk ... @@ -2206,7 +2211,7 @@ Your cooperation is appreciated. Partitions are handled as for major 48. -144 char Encapsulated PPP + 144 char Encapsulated PPP 0 = /dev/pppox0 First PPP over Ethernet ... 63 = /dev/pppox63 64th PPP over Ethernet @@ -2216,11 +2221,11 @@ Your cooperation is appreciated. The SST 5136-DN DeviceNet interface driver has been relocated to major 183 due to an unfortunate conflict. -144 block Expansion Area #1 for more non-device (e.g. NFS) mounts + 144 block Expansion Area #1 for more non-device (e.g. NFS) mounts 0 = mounted device 256 255 = mounted device 511 -145 char SAM9407-based soundcard + 145 char SAM9407-based soundcard 0 = /dev/sam0_mixer 1 = /dev/sam0_sequencer 2 = /dev/sam0_midi00 @@ -2241,66 +2246,66 @@ Your cooperation is appreciated. addons, which are sam9407 specific. OSS can be operated simultaneously, taking care of the codec. -145 block Expansion Area #2 for more non-device (e.g. NFS) mounts + 145 block Expansion Area #2 for more non-device (e.g. NFS) mounts 0 = mounted device 512 255 = mounted device 767 -146 char SYSTRAM SCRAMNet mirrored-memory network + 146 char SYSTRAM SCRAMNet mirrored-memory network 0 = /dev/scramnet0 First SCRAMNet device 1 = /dev/scramnet1 Second SCRAMNet device ... -146 block Expansion Area #3 for more non-device (e.g. NFS) mounts + 146 block Expansion Area #3 for more non-device (e.g. NFS) mounts 0 = mounted device 768 255 = mounted device 1023 -147 char Aureal Semiconductor Vortex Audio device + 147 char Aureal Semiconductor Vortex Audio device 0 = /dev/aureal0 First Aureal Vortex 1 = /dev/aureal1 Second Aureal Vortex ... -147 block Distributed Replicated Block Device (DRBD) + 147 block Distributed Replicated Block Device (DRBD) 0 = /dev/drbd0 First DRBD device 1 = /dev/drbd1 Second DRBD device ... -148 char Technology Concepts serial card + 148 char Technology Concepts serial card 0 = /dev/ttyT0 First TCL port 1 = /dev/ttyT1 Second TCL port ... -149 char Technology Concepts serial card - alternate devices + 149 char Technology Concepts serial card - alternate devices 0 = /dev/cut0 Callout device for ttyT0 1 = /dev/cut0 Callout device for ttyT1 ... -150 char Real-Time Linux FIFOs + 150 char Real-Time Linux FIFOs 0 = /dev/rtf0 First RTLinux FIFO 1 = /dev/rtf1 Second RTLinux FIFO ... -151 char DPT I2O SmartRaid V controller + 151 char DPT I2O SmartRaid V controller 0 = /dev/dpti0 First DPT I2O adapter 1 = /dev/dpti1 Second DPT I2O adapter ... -152 char EtherDrive Control Device + 152 char EtherDrive Control Device 0 = /dev/etherd/ctl Connect/Disconnect an EtherDrive 1 = /dev/etherd/err Monitor errors 2 = /dev/etherd/raw Raw AoE packet monitor -152 block EtherDrive Block Devices + 152 block EtherDrive Block Devices 0 = /dev/etherd/0 EtherDrive 0 ... 255 = /dev/etherd/255 EtherDrive 255 -153 char SPI Bus Interface (sometimes referred to as MicroWire) + 153 char SPI Bus Interface (sometimes referred to as MicroWire) 0 = /dev/spi0 First SPI device on the bus 1 = /dev/spi1 Second SPI device on the bus ... 15 = /dev/spi15 Sixteenth SPI device on the bus -153 block Enhanced Metadisk RAID (EMD) storage units + 153 block Enhanced Metadisk RAID (EMD) storage units 0 = /dev/emd/0 First unit 1 = /dev/emd/0p1 Partition 1 on First unit 2 = /dev/emd/0p2 Partition 2 on First unit @@ -2316,41 +2321,41 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. -154 char Specialix RIO serial card + 154 char Specialix RIO serial card 0 = /dev/ttySR0 First RIO port ... 255 = /dev/ttySR255 256th RIO port -155 char Specialix RIO serial card - alternate devices + 155 char Specialix RIO serial card - alternate devices 0 = /dev/cusr0 Callout device for ttySR0 ... 255 = /dev/cusr255 Callout device for ttySR255 -156 char Specialix RIO serial card + 156 char Specialix RIO serial card 0 = /dev/ttySR256 257th RIO port ... 255 = /dev/ttySR511 512th RIO port -157 char Specialix RIO serial card - alternate devices + 157 char Specialix RIO serial card - alternate devices 0 = /dev/cusr256 Callout device for ttySR256 ... 255 = /dev/cusr511 Callout device for ttySR511 -158 char Dialogic GammaLink fax driver + 158 char Dialogic GammaLink fax driver 0 = /dev/gfax0 GammaLink channel 0 1 = /dev/gfax1 GammaLink channel 1 ... -159 char RESERVED + 159 char RESERVED -159 block RESERVED + 159 block RESERVED -160 char General Purpose Instrument Bus (GPIB) + 160 char General Purpose Instrument Bus (GPIB) 0 = /dev/gpib0 First GPIB bus 1 = /dev/gpib1 Second GPIB bus ... -160 block Carmel 8-port SATA Disks on First Controller + 160 block Carmel 8-port SATA Disks on First Controller 0 = /dev/carmel/0 SATA disk 0 whole disk 1 = /dev/carmel/0p1 SATA disk 0 partition 1 ... @@ -2365,7 +2370,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 31. -161 char IrCOMM devices (IrDA serial/parallel emulation) + 161 char IrCOMM devices (IrDA serial/parallel emulation) 0 = /dev/ircomm0 First IrCOMM device 1 = /dev/ircomm1 Second IrCOMM device ... @@ -2373,7 +2378,7 @@ Your cooperation is appreciated. 17 = /dev/irlpt1 Second IrLPT device ... -161 block Carmel 8-port SATA Disks on Second Controller + 161 block Carmel 8-port SATA Disks on Second Controller 0 = /dev/carmel/8 SATA disk 8 whole disk 1 = /dev/carmel/8p1 SATA disk 8 partition 1 ... @@ -2388,17 +2393,17 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 31. -162 char Raw block device interface + 162 char Raw block device interface 0 = /dev/rawctl Raw I/O control device 1 = /dev/raw/raw1 First raw I/O device 2 = /dev/raw/raw2 Second raw I/O device ... - max minor number of raw device is set by kernel config - MAX_RAW_DEVS or raw module parameter 'max_raw_devs' + max minor number of raw device is set by kernel config + MAX_RAW_DEVS or raw module parameter 'max_raw_devs' -163 char + 163 char -164 char Chase Research AT/PCI-Fast serial card + 164 char Chase Research AT/PCI-Fast serial card 0 = /dev/ttyCH0 AT/PCI-Fast board 0, port 0 ... 15 = /dev/ttyCH15 AT/PCI-Fast board 0, port 15 @@ -2412,67 +2417,67 @@ Your cooperation is appreciated. ... 63 = /dev/ttyCH63 AT/PCI-Fast board 3, port 15 -165 char Chase Research AT/PCI-Fast serial card - alternate devices + 165 char Chase Research AT/PCI-Fast serial card - alternate devices 0 = /dev/cuch0 Callout device for ttyCH0 ... 63 = /dev/cuch63 Callout device for ttyCH63 -166 char ACM USB modems + 166 char ACM USB modems 0 = /dev/ttyACM0 First ACM modem 1 = /dev/ttyACM1 Second ACM modem ... -167 char ACM USB modems - alternate devices + 167 char ACM USB modems - alternate devices 0 = /dev/cuacm0 Callout device for ttyACM0 1 = /dev/cuacm1 Callout device for ttyACM1 ... -168 char Eracom CSA7000 PCI encryption adaptor + 168 char Eracom CSA7000 PCI encryption adaptor 0 = /dev/ecsa0 First CSA7000 1 = /dev/ecsa1 Second CSA7000 ... -169 char Eracom CSA8000 PCI encryption adaptor + 169 char Eracom CSA8000 PCI encryption adaptor 0 = /dev/ecsa8-0 First CSA8000 1 = /dev/ecsa8-1 Second CSA8000 ... -170 char AMI MegaRAC remote access controller + 170 char AMI MegaRAC remote access controller 0 = /dev/megarac0 First MegaRAC card 1 = /dev/megarac1 Second MegaRAC card ... -171 char Reserved for IEEE 1394 (Firewire) + 171 char Reserved for IEEE 1394 (Firewire) -172 char Moxa Intellio serial card + 172 char Moxa Intellio serial card 0 = /dev/ttyMX0 First Moxa port 1 = /dev/ttyMX1 Second Moxa port ... 127 = /dev/ttyMX127 128th Moxa port 128 = /dev/moxactl Moxa control port -173 char Moxa Intellio serial card - alternate devices + 173 char Moxa Intellio serial card - alternate devices 0 = /dev/cumx0 Callout device for ttyMX0 1 = /dev/cumx1 Callout device for ttyMX1 ... 127 = /dev/cumx127 Callout device for ttyMX127 -174 char SmartIO serial card + 174 char SmartIO serial card 0 = /dev/ttySI0 First SmartIO port 1 = /dev/ttySI1 Second SmartIO port ... -175 char SmartIO serial card - alternate devices + 175 char SmartIO serial card - alternate devices 0 = /dev/cusi0 Callout device for ttySI0 1 = /dev/cusi1 Callout device for ttySI1 ... -176 char nCipher nFast PCI crypto accelerator + 176 char nCipher nFast PCI crypto accelerator 0 = /dev/nfastpci0 First nFast PCI device 1 = /dev/nfastpci1 First nFast PCI device ... -177 char TI PCILynx memory spaces + 177 char TI PCILynx memory spaces 0 = /dev/pcilynx/aux0 AUX space of first PCILynx card ... 15 = /dev/pcilynx/aux15 AUX space of 16th PCILynx card @@ -2483,12 +2488,12 @@ Your cooperation is appreciated. ... 47 = /dev/pcilynx/ram15 RAM space of 16th PCILynx card -178 char Giganet cLAN1xxx virtual interface adapter + 178 char Giganet cLAN1xxx virtual interface adapter 0 = /dev/clanvi0 First cLAN adapter 1 = /dev/clanvi1 Second cLAN adapter ... -179 block MMC block devices + 179 block MMC block devices 0 = /dev/mmcblk0 First SD/MMC card 1 = /dev/mmcblk0p1 First partition on first MMC card 8 = /dev/mmcblk1 Second SD/MMC card @@ -2500,12 +2505,12 @@ Your cooperation is appreciated. bump the offset between each card to be the configured value instead of the default 8. -179 char CCube DVXChip-based PCI products + 179 char CCube DVXChip-based PCI products 0 = /dev/dvxirq0 First DVX device 1 = /dev/dvxirq1 Second DVX device ... -180 char USB devices + 180 char USB devices 0 = /dev/usb/lp0 First USB printer ... 15 = /dev/usb/lp15 16th USB printer @@ -2539,23 +2544,23 @@ Your cooperation is appreciated. ... 209 = /dev/usb/yurex16 16th USB Yurex device -180 block USB block devices + 180 block USB block devices 0 = /dev/uba First USB block device 8 = /dev/ubb Second USB block device 16 = /dev/ubc Third USB block device - ... + ... -181 char Conrad Electronic parallel port radio clocks + 181 char Conrad Electronic parallel port radio clocks 0 = /dev/pcfclock0 First Conrad radio clock 1 = /dev/pcfclock1 Second Conrad radio clock ... -182 char Picture Elements THR2 binarizer + 182 char Picture Elements THR2 binarizer 0 = /dev/pethr0 First THR2 board 1 = /dev/pethr1 Second THR2 board ... -183 char SST 5136-DN DeviceNet interface + 183 char SST 5136-DN DeviceNet interface 0 = /dev/ss5136dn0 First DeviceNet interface 1 = /dev/ss5136dn1 Second DeviceNet interface ... @@ -2563,12 +2568,12 @@ Your cooperation is appreciated. This device used to be assigned to major number 144. It had to be moved due to an unfortunate conflict. -184 char Picture Elements' video simulator/sender + 184 char Picture Elements' video simulator/sender 0 = /dev/pevss0 First sender board 1 = /dev/pevss1 Second sender board ... -185 char InterMezzo high availability file system + 185 char InterMezzo high availability file system 0 = /dev/intermezzo0 First cache manager 1 = /dev/intermezzo1 Second cache manager ... @@ -2576,48 +2581,48 @@ Your cooperation is appreciated. See http://web.archive.org/web/20080115195241/ http://inter-mezzo.org/index.html -186 char Object-based storage control device + 186 char Object-based storage control device 0 = /dev/obd0 First obd control device 1 = /dev/obd1 Second obd control device ... See ftp://ftp.lustre.org/pub/obd for code and information. -187 char DESkey hardware encryption device + 187 char DESkey hardware encryption device 0 = /dev/deskey0 First DES key 1 = /dev/deskey1 Second DES key ... -188 char USB serial converters + 188 char USB serial converters 0 = /dev/ttyUSB0 First USB serial converter 1 = /dev/ttyUSB1 Second USB serial converter ... -189 char USB serial converters - alternate devices + 189 char USB serial converters - alternate devices 0 = /dev/cuusb0 Callout device for ttyUSB0 1 = /dev/cuusb1 Callout device for ttyUSB1 ... -190 char Kansas City tracker/tuner card + 190 char Kansas City tracker/tuner card 0 = /dev/kctt0 First KCT/T card 1 = /dev/kctt1 Second KCT/T card ... -191 char Reserved for PCMCIA + 191 char Reserved for PCMCIA -192 char Kernel profiling interface + 192 char Kernel profiling interface 0 = /dev/profile Profiling control device 1 = /dev/profile0 Profiling device for CPU 0 2 = /dev/profile1 Profiling device for CPU 1 ... -193 char Kernel event-tracing interface + 193 char Kernel event-tracing interface 0 = /dev/trace Tracing control device 1 = /dev/trace0 Tracing device for CPU 0 2 = /dev/trace1 Tracing device for CPU 1 ... -194 char linVideoStreams (LINVS) + 194 char linVideoStreams (LINVS) 0 = /dev/mvideo/status0 Video compression status 1 = /dev/mvideo/stream0 Video stream 2 = /dev/mvideo/frame0 Single compressed frame @@ -2633,13 +2638,13 @@ Your cooperation is appreciated. 240 = /dev/mvideo/status15 16th device ... -195 char Nvidia graphics devices + 195 char Nvidia graphics devices 0 = /dev/nvidia0 First Nvidia card 1 = /dev/nvidia1 Second Nvidia card ... 255 = /dev/nvidiactl Nvidia card control device -196 char Tormenta T1 card + 196 char Tormenta T1 card 0 = /dev/tor/0 Master control channel for all cards 1 = /dev/tor/1 First DS0 2 = /dev/tor/2 Second DS0 @@ -2649,24 +2654,24 @@ Your cooperation is appreciated. 50 = /dev/tor/50 Second pseudo-channel ... -197 char OpenTNF tracing facility + 197 char OpenTNF tracing facility 0 = /dev/tnf/t0 Trace 0 data extraction 1 = /dev/tnf/t1 Trace 1 data extraction ... 128 = /dev/tnf/status Tracing facility status 130 = /dev/tnf/trace Tracing device -198 char Total Impact TPMP2 quad coprocessor PCI card + 198 char Total Impact TPMP2 quad coprocessor PCI card 0 = /dev/tpmp2/0 First card 1 = /dev/tpmp2/1 Second card ... -199 char Veritas volume manager (VxVM) volumes + 199 char Veritas volume manager (VxVM) volumes 0 = /dev/vx/rdsk/*/* First volume 1 = /dev/vx/rdsk/*/* Second volume ... -199 block Veritas volume manager (VxVM) volumes + 199 block Veritas volume manager (VxVM) volumes 0 = /dev/vx/dsk/*/* First volume 1 = /dev/vx/dsk/*/* Second volume ... @@ -2674,19 +2679,19 @@ Your cooperation is appreciated. The namespace in these directories is maintained by the user space VxVM software. -200 char Veritas VxVM configuration interface - 0 = /dev/vx/config Configuration access node - 1 = /dev/vx/trace Volume i/o trace access node - 2 = /dev/vx/iod Volume i/o daemon access node - 3 = /dev/vx/info Volume information access node - 4 = /dev/vx/task Volume tasks access node - 5 = /dev/vx/taskmon Volume tasks monitor daemon + 200 char Veritas VxVM configuration interface + 0 = /dev/vx/config Configuration access node + 1 = /dev/vx/trace Volume i/o trace access node + 2 = /dev/vx/iod Volume i/o daemon access node + 3 = /dev/vx/info Volume information access node + 4 = /dev/vx/task Volume tasks access node + 5 = /dev/vx/taskmon Volume tasks monitor daemon -201 char Veritas VxVM dynamic multipathing driver + 201 char Veritas VxVM dynamic multipathing driver 0 = /dev/vx/rdmp/* First multipath device 1 = /dev/vx/rdmp/* Second multipath device ... -201 block Veritas VxVM dynamic multipathing driver + 201 block Veritas VxVM dynamic multipathing driver 0 = /dev/vx/dmp/* First multipath device 1 = /dev/vx/dmp/* Second multipath device ... @@ -2694,28 +2699,28 @@ Your cooperation is appreciated. The namespace in these directories is maintained by the user space VxVM software. -202 char CPU model-specific registers + 202 char CPU model-specific registers 0 = /dev/cpu/0/msr MSRs on CPU 0 1 = /dev/cpu/1/msr MSRs on CPU 1 ... -202 block Xen Virtual Block Device + 202 block Xen Virtual Block Device 0 = /dev/xvda First Xen VBD whole disk 16 = /dev/xvdb Second Xen VBD whole disk 32 = /dev/xvdc Third Xen VBD whole disk ... 240 = /dev/xvdp Sixteenth Xen VBD whole disk - Partitions are handled in the same way as for IDE - disks (see major number 3) except that the limit on - partitions is 15. + Partitions are handled in the same way as for IDE + disks (see major number 3) except that the limit on + partitions is 15. -203 char CPU CPUID information + 203 char CPU CPUID information 0 = /dev/cpu/0/cpuid CPUID on CPU 0 1 = /dev/cpu/1/cpuid CPUID on CPU 1 ... -204 char Low-density serial ports + 204 char Low-density serial ports 0 = /dev/ttyLU0 LinkUp Systems L72xx UART - port 0 1 = /dev/ttyLU1 LinkUp Systems L72xx UART - port 1 2 = /dev/ttyLU2 LinkUp Systems L72xx UART - port 2 @@ -2787,7 +2792,7 @@ Your cooperation is appreciated. 211 = /dev/ttyMAX2 MAX3100 serial port 2 212 = /dev/ttyMAX3 MAX3100 serial port 3 -205 char Low-density serial ports (alternate device) + 205 char Low-density serial ports (alternate device) 0 = /dev/culu0 Callout device for ttyLU0 1 = /dev/culu1 Callout device for ttyLU1 2 = /dev/culu2 Callout device for ttyLU2 @@ -2823,7 +2828,7 @@ Your cooperation is appreciated. 82 = /dev/cuvr0 Callout device for ttyVR0 83 = /dev/cuvr1 Callout device for ttyVR1 -206 char OnStream SC-x0 tape devices + 206 char OnStream SC-x0 tape devices 0 = /dev/osst0 First OnStream SCSI tape, mode 0 1 = /dev/osst1 Second OnStream SCSI tape, mode 0 ... @@ -2857,7 +2862,7 @@ Your cooperation is appreciated. driver as well. The ADR-x0 drives are QIC-157 compliant and don't need osst. -207 char Compaq ProLiant health feature indicate + 207 char Compaq ProLiant health feature indicate 0 = /dev/cpqhealth/cpqw Redirector interface 1 = /dev/cpqhealth/crom EISA CROM 2 = /dev/cpqhealth/cdt Data Table @@ -2871,17 +2876,17 @@ Your cooperation is appreciated. 10 = /dev/cpqhealth/cram CMOS interface 11 = /dev/cpqhealth/cpci PCI IRQ interface -208 char User space serial ports + 208 char User space serial ports 0 = /dev/ttyU0 First user space serial port 1 = /dev/ttyU1 Second user space serial port ... -209 char User space serial ports (alternate devices) + 209 char User space serial ports (alternate devices) 0 = /dev/cuu0 Callout device for ttyU0 1 = /dev/cuu1 Callout device for ttyU1 ... -210 char SBE, Inc. sync/async serial card + 210 char SBE, Inc. sync/async serial card 0 = /dev/sbei/wxcfg0 Configuration device for board 0 1 = /dev/sbei/dld0 Download device for board 0 2 = /dev/sbei/wan00 WAN device, port 0, board 0 @@ -2906,12 +2911,12 @@ Your cooperation is appreciated. Yes, each board is really spaced 10 (decimal) apart. -211 char Addinum CPCI1500 digital I/O card + 211 char Addinum CPCI1500 digital I/O card 0 = /dev/addinum/cpci1500/0 First CPCI1500 card 1 = /dev/addinum/cpci1500/1 Second CPCI1500 card ... -212 char LinuxTV.org DVB driver subsystem + 212 char LinuxTV.org DVB driver subsystem 0 = /dev/dvb/adapter0/video0 first video decoder of first card 1 = /dev/dvb/adapter0/audio0 first audio decoder of first card 2 = /dev/dvb/adapter0/sec0 (obsolete/unused) @@ -2929,34 +2934,34 @@ Your cooperation is appreciated. ... 196 = /dev/dvb/adapter3/video0 first video decoder of fourth card -216 char Bluetooth RFCOMM TTY devices + 216 char Bluetooth RFCOMM TTY devices 0 = /dev/rfcomm0 First Bluetooth RFCOMM TTY device 1 = /dev/rfcomm1 Second Bluetooth RFCOMM TTY device ... -217 char Bluetooth RFCOMM TTY devices (alternate devices) + 217 char Bluetooth RFCOMM TTY devices (alternate devices) 0 = /dev/curf0 Callout device for rfcomm0 1 = /dev/curf1 Callout device for rfcomm1 ... -218 char The Logical Company bus Unibus/Qbus adapters + 218 char The Logical Company bus Unibus/Qbus adapters 0 = /dev/logicalco/bci/0 First bus adapter 1 = /dev/logicalco/bci/1 First bus adapter ... -219 char The Logical Company DCI-1300 digital I/O card + 219 char The Logical Company DCI-1300 digital I/O card 0 = /dev/logicalco/dci1300/0 First DCI-1300 card 1 = /dev/logicalco/dci1300/1 Second DCI-1300 card ... -220 char Myricom Myrinet "GM" board + 220 char Myricom Myrinet "GM" board 0 = /dev/myricom/gm0 First Myrinet GM board 1 = /dev/myricom/gmp0 First board "root access" 2 = /dev/myricom/gm1 Second Myrinet GM board 3 = /dev/myricom/gmp1 Second board "root access" ... -221 char VME bus + 221 char VME bus 0 = /dev/bus/vme/m0 First master image 1 = /dev/bus/vme/m1 Second master image 2 = /dev/bus/vme/m2 Third master image @@ -2971,38 +2976,38 @@ Your cooperation is appreciated. same interface. For interface documentation see http://www.vmelinux.org/. -224 char A2232 serial card + 224 char A2232 serial card 0 = /dev/ttyY0 First A2232 port 1 = /dev/ttyY1 Second A2232 port ... -225 char A2232 serial card (alternate devices) + 225 char A2232 serial card (alternate devices) 0 = /dev/cuy0 Callout device for ttyY0 1 = /dev/cuy1 Callout device for ttyY1 ... -226 char Direct Rendering Infrastructure (DRI) + 226 char Direct Rendering Infrastructure (DRI) 0 = /dev/dri/card0 First graphics card 1 = /dev/dri/card1 Second graphics card ... -227 char IBM 3270 terminal Unix tty access + 227 char IBM 3270 terminal Unix tty access 1 = /dev/3270/tty1 First 3270 terminal 2 = /dev/3270/tty2 Seconds 3270 terminal ... -228 char IBM 3270 terminal block-mode access + 228 char IBM 3270 terminal block-mode access 0 = /dev/3270/tub Controlling interface 1 = /dev/3270/tub1 First 3270 terminal 2 = /dev/3270/tub2 Second 3270 terminal ... -229 char IBM iSeries/pSeries virtual console + 229 char IBM iSeries/pSeries virtual console 0 = /dev/hvc0 First console port 1 = /dev/hvc1 Second console port ... -230 char IBM iSeries virtual tape + 230 char IBM iSeries virtual tape 0 = /dev/iseries/vt0 First virtual tape, mode 0 1 = /dev/iseries/vt1 Second virtual tape, mode 0 ... @@ -3033,7 +3038,7 @@ Your cooperation is appreciated. ioctl()'s can be used to rewind the tape regardless of the device used to access it. -231 char InfiniBand + 231 char InfiniBand 0 = /dev/infiniband/umad0 1 = /dev/infiniband/umad1 ... @@ -3047,7 +3052,7 @@ Your cooperation is appreciated. ... 159 = /dev/infiniband/uverbs31 31st InfiniBand verbs device -232 char Biometric Devices + 232 char Biometric Devices 0 = /dev/biometric/sensor0/fingerprint first fingerprint sensor on first device 1 = /dev/biometric/sensor0/iris first iris sensor on first device 2 = /dev/biometric/sensor0/retina first retina sensor on first device @@ -3060,7 +3065,7 @@ Your cooperation is appreciated. 20 = /dev/biometric/sensor2/fingerprint first fingerprint sensor on third device ... -233 char PathScale InfiniPath interconnect + 233 char PathScale InfiniPath interconnect 0 = /dev/ipath Primary device for programs (any unit) 1 = /dev/ipath0 Access specifically to unit 0 2 = /dev/ipath1 Access specifically to unit 1 @@ -3069,18 +3074,18 @@ Your cooperation is appreciated. 129 = /dev/ipath_sma Device used by Subnet Management Agent 130 = /dev/ipath_diag Device used by diagnostics programs -234-254 char RESERVED FOR DYNAMIC ASSIGNMENT + 234-254 char RESERVED FOR DYNAMIC ASSIGNMENT Character devices that request a dynamic allocation of major number will take numbers starting from 254 and downward. -240-254 block LOCAL/EXPERIMENTAL USE + 240-254 block LOCAL/EXPERIMENTAL USE Allocated for local/experimental use. For devices not assigned official numbers, these ranges should be used in order to avoid conflicting with future assignments. -255 char RESERVED + 255 char RESERVED -255 block RESERVED + 255 block RESERVED This major is reserved to assist the expansion to a larger number space. No device nodes with this major @@ -3088,25 +3093,25 @@ Your cooperation is appreciated. (This is probably not true anymore, but I'll leave it for now /Torben) ----LARGE MAJORS!!!!!--- + ---LARGE MAJORS!!!!!--- -256 char Equinox SST multi-port serial boards + 256 char Equinox SST multi-port serial boards 0 = /dev/ttyEQ0 First serial port on first Equinox SST board 127 = /dev/ttyEQ127 Last serial port on first Equinox SST board 128 = /dev/ttyEQ128 First serial port on second Equinox SST board ... 1027 = /dev/ttyEQ1027 Last serial port on eighth Equinox SST board -256 block Resident Flash Disk Flash Translation Layer + 256 block Resident Flash Disk Flash Translation Layer 0 = /dev/rfda First RFD FTL layer 16 = /dev/rfdb Second RFD FTL layer ... 240 = /dev/rfdp 16th RFD FTL layer -257 char Phoenix Technologies Cryptographic Services Driver + 257 char Phoenix Technologies Cryptographic Services Driver 0 = /dev/ptlsec Crypto Services Driver -257 block SSFDC Flash Translation Layer filesystem + 257 block SSFDC Flash Translation Layer filesystem 0 = /dev/ssfdca First SSFDC layer 8 = /dev/ssfdcb Second SSFDC layer 16 = /dev/ssfdcc Third SSFDC layer @@ -3116,26 +3121,28 @@ Your cooperation is appreciated. 48 = /dev/ssfdcg 7th SSFDC layer 56 = /dev/ssfdch 8th SSFDC layer -258 block ROM/Flash read-only translation layer + 258 block ROM/Flash read-only translation layer 0 = /dev/blockrom0 First ROM card's translation layer interface 1 = /dev/blockrom1 Second ROM card's translation layer interface ... -259 block Block Extended Major + 259 block Block Extended Major Used dynamically to hold additional partition minor numbers and allow large numbers of partitions per device -259 char FPGA configuration interfaces + 259 char FPGA configuration interfaces 0 = /dev/icap0 First Xilinx internal configuration 1 = /dev/icap1 Second Xilinx internal configuration -260 char OSD (Object-based-device) SCSI Device + 260 char OSD (Object-based-device) SCSI Device 0 = /dev/osd0 First OSD Device 1 = /dev/osd1 Second OSD Device ... 255 = /dev/osd255 256th OSD Device - **** ADDITIONAL /dev DIRECTORY ENTRIES + +Additional ``/dev/`` directory entries +-------------------------------------- This section details additional entries that should or may exist in the /dev directory. It is preferred that symbolic links use the same @@ -3143,24 +3150,29 @@ form (absolute or relative) as is indicated here. Links are classified as "hard" or "symbolic" depending on the preferred type of link; if possible, the indicated type of link should be used. - - Compulsory links +Compulsory links +++++++++++++++++ These links should exist on all systems: +=============== =============== =============== =============================== /dev/fd /proc/self/fd symbolic File descriptors /dev/stdin fd/0 symbolic stdin file descriptor /dev/stdout fd/1 symbolic stdout file descriptor /dev/stderr fd/2 symbolic stderr file descriptor /dev/nfsd socksys symbolic Required by iBCS-2 /dev/X0R null symbolic Required by iBCS-2 +=============== =============== =============== =============================== -Note: /dev/X0R is <letter X>-<digit 0>-<letter R>. +Note: ``/dev/X0R`` is <letter X>-<digit 0>-<letter R>. - Recommended links +Recommended links ++++++++++++++++++ It is recommended that these links exist on all systems: + +=============== =============== =============== =============================== /dev/core /proc/kcore symbolic Backward compatibility /dev/ramdisk ram0 symbolic Backward compatibility /dev/ftape qft0 symbolic Backward compatibility @@ -3168,14 +3180,17 @@ It is recommended that these links exist on all systems: /dev/radio radio0 symbolic Backward compatibility /dev/i2o* /dev/i2o/* symbolic Backward compatibility /dev/scd? sr? hard Alternate SCSI CD-ROM name +=============== =============== =============== =============================== - Locally defined links +Locally defined links ++++++++++++++++++++++ The following links may be established locally to conform to the configuration of the system. This is merely a tabulation of existing practice, and does not constitute a recommendation. However, if they exist, they should have the following uses. +=============== =============== =============== =============================== /dev/mouse mouse port symbolic Current mouse device /dev/tape tape device symbolic Current tape device /dev/cdrom CD-ROM device symbolic Current CD-ROM device @@ -3184,38 +3199,46 @@ exist, they should have the following uses. /dev/modem modem port symbolic Current dialout device /dev/root root device symbolic Current root filesystem /dev/swap swap device symbolic Current swap device +=============== =============== =============== =============================== -/dev/modem should not be used for a modem which supports dialin as +``/dev/modem`` should not be used for a modem which supports dialin as well as dialout, as it tends to cause lock file problems. If it -exists, /dev/modem should point to the appropriate primary TTY device +exists, ``/dev/modem`` should point to the appropriate primary TTY device (the use of the alternate callout devices is deprecated). -For SCSI devices, /dev/tape and /dev/cdrom should point to the -``cooked'' devices (/dev/st* and /dev/sr*, respectively), whereas -/dev/cdwriter and /dev/scanner should point to the appropriate generic +For SCSI devices, ``/dev/tape`` and ``/dev/cdrom`` should point to the +*cooked* devices (``/dev/st*`` and ``/dev/sr*``, respectively), whereas +``/dev/cdwriter`` and /dev/scanner should point to the appropriate generic SCSI devices (/dev/sg*). -/dev/mouse may point to a primary serial TTY device, a hardware mouse -device, or a socket for a mouse driver program (e.g. /dev/gpmdata). +``/dev/mouse`` may point to a primary serial TTY device, a hardware mouse +device, or a socket for a mouse driver program (e.g. ``/dev/gpmdata``). - Sockets and pipes +Sockets and pipes ++++++++++++++++++ Non-transient sockets and named pipes may exist in /dev. Common entries are: +=============== =============== =============================================== /dev/printer socket lpd local socket /dev/log socket syslog local socket /dev/gpmdata socket gpm mouse multiplexer +=============== =============== =============================================== - Mount points +Mount points +++++++++++++ The following names are reserved for mounting special filesystems under /dev. These special filesystems provide kernel interfaces that cannot be provided with standard device nodes. +=============== =============== =============================================== /dev/pts devpts PTY slave filesystem /dev/shm tmpfs POSIX shared memory maintenance access +=============== =============== =============================================== - **** TERMINAL DEVICES +Terminal devices +---------------- Terminal, or TTY devices are a special class of character devices. A terminal device is any device that could act as a controlling terminal @@ -3232,42 +3255,44 @@ conventions include several historical warts; some of these are Linux-specific, some were inherited from other systems, and some reflect Linux outgrowing a borrowed convention. -A hash mark (#) in a device name is used here to indicate a decimal +A hash mark (``#``) in a device name is used here to indicate a decimal number without leading zeroes. - Virtual consoles and the console device +Virtual consoles and the console device ++++++++++++++++++++++++++++++++++++++++ Virtual consoles are full-screen terminal displays on the system video -monitor. Virtual consoles are named /dev/tty#, with numbering -starting at /dev/tty1; /dev/tty0 is the current virtual console. -/dev/tty0 is the device that should be used to access the system video +monitor. Virtual consoles are named ``/dev/tty#``, with numbering +starting at ``/dev/tty1``; ``/dev/tty0`` is the current virtual console. +``/dev/tty0`` is the device that should be used to access the system video card on those architectures for which the frame buffer devices -(/dev/fb*) are not applicable. Do not use /dev/console +(``/dev/fb*``) are not applicable. Do not use ``/dev/console`` for this purpose. -The console device, /dev/console, is the device to which system +The console device, ``/dev/console``, is the device to which system messages should be sent, and on which logins should be permitted in -single-user mode. Starting with Linux 2.1.71, /dev/console is managed +single-user mode. Starting with Linux 2.1.71, ``/dev/console`` is managed by the kernel; for previous versions it should be a symbolic link to -either /dev/tty0, a specific virtual console such as /dev/tty1, or to -a serial port primary (tty*, not cu*) device, depending on the +either ``/dev/tty0``, a specific virtual console such as ``/dev/tty1``, or to +a serial port primary (``tty*``, not ``cu*``) device, depending on the configuration of the system. - Serial ports +Serial ports +++++++++++++ Serial ports are RS-232 serial ports and any device which simulates one, either in hardware (such as internal modems) or in software (such as the ISDN driver.) Under Linux, each serial ports has two device names, the primary or callin device and the alternate or callout one. Each kind of device is indicated by a different letter. For any -letter X, the names of the devices are /dev/ttyX# and /dev/cux#, -respectively; for historical reasons, /dev/ttyS# and /dev/ttyC# -correspond to /dev/cua# and /dev/cub#. In the future, it should be +letter X, the names of the devices are ``/dev/ttyX#`` and ``/dev/cux#``, +respectively; for historical reasons, ``/dev/ttyS#`` and ``/dev/ttyC#`` +correspond to ``/dev/cua#`` and ``/dev/cub#``. In the future, it should be expected that multiple letters will be used; all letters will be upper -case for the "tty" device (e.g. /dev/ttyDP#) and lower case for the -"cu" device (e.g. /dev/cudp#). +case for the "tty" device (e.g. ``/dev/ttyDP#``) and lower case for the +"cu" device (e.g. ``/dev/cudp#``). -The names /dev/ttyQ# and /dev/cuq# are reserved for local use. +The names ``/dev/ttyQ#`` and ``/dev/cuq#`` are reserved for local use. The alternate devices provide for kernel-based exclusion and somewhat different defaults than the primary devices. Their main purpose is to @@ -3276,7 +3301,7 @@ support for serial ports. Their use is deprecated, and they may be removed from a future version of Linux. Arbitration of serial ports is provided by the use of lock files with -the names /var/lock/LCK..ttyX#. The contents of the lock file should +the names ``/var/lock/LCK..ttyX#``. The contents of the lock file should be the PID of the locking process as an ASCII number. It is common practice to install links such as /dev/modem @@ -3287,9 +3312,9 @@ that a lock file be installed with the corresponding alternate device. In order to avoid deadlocks, it is recommended that the locks are acquired in the following order, and released in the reverse: - 1. The symbolic link name, if any (/var/lock/LCK..modem) - 2. The "tty" name (/var/lock/LCK..ttyS2) - 3. The alternate device name (/var/lock/LCK..cua2) + 1. The symbolic link name, if any (``/var/lock/LCK..modem``) + 2. The "tty" name (``/var/lock/LCK..ttyS2``) + 3. The alternate device name (``/var/lock/LCK..cua2``) In the case of nested symbolic links, the lock files should be installed in the order the symlinks are resolved. @@ -3300,13 +3325,14 @@ to create lock files for the corresponding alternate device names should take into account the possibility of being used on a non-serial port TTY, for which no alternate device would exist. - Pseudoterminals (PTYs) +Pseudoterminals (PTYs) +++++++++++++++++++++++ Pseudoterminals, or PTYs, are used to create login sessions or provide other capabilities requiring a TTY line discipline (including SLIP or PPP capability) to arbitrary data-generation processes. Each PTY has -a master side, named /dev/pty[p-za-e][0-9a-f], and a slave side, named -/dev/tty[p-za-e][0-9a-f]. The kernel arbitrates the use of PTYs by +a master side, named ``/dev/pty[p-za-e][0-9a-f]``, and a slave side, named +``/dev/tty[p-za-e][0-9a-f]``. The kernel arbitrates the use of PTYs by allowing each master side to be opened only once. Once the master side has been opened, the corresponding slave device @@ -3316,10 +3342,9 @@ of a bidirectional pipe with TTY capabilities. Recent versions of the Linux kernels and GNU libc contain support for the System V/Unix98 naming scheme for PTYs, which assigns a common -device, /dev/ptmx, to all the masters (opening it will automatically -give you a previously unassigned PTY) and a subdirectory, /dev/pts, -for the slaves; the slaves are named with decimal integers (/dev/pts/# +device, ``/dev/ptmx``, to all the masters (opening it will automatically +give you a previously unassigned PTY) and a subdirectory, ``/dev/pts``, +for the slaves; the slaves are named with decimal integers (``/dev/pts/#`` in our notation). This removes the problem of exhausting the namespace and enables the kernel to automatically create the device nodes for the slaves on demand using the "devpts" filesystem. - diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst new file mode 100644 index 0000000..88adcfd --- /dev/null +++ b/Documentation/admin-guide/dynamic-debug-howto.rst @@ -0,0 +1,353 @@ +Dynamic debug ++++++++++++++ + + +Introduction +============ + +This document describes how to use the dynamic debug (dyndbg) feature. + +Dynamic debug is designed to allow you to dynamically enable/disable +kernel code to obtain additional kernel information. Currently, if +``CONFIG_DYNAMIC_DEBUG`` is set, then all ``pr_debug()``/``dev_dbg()`` and +``print_hex_dump_debug()``/``print_hex_dump_bytes()`` calls can be dynamically +enabled per-callsite. + +If ``CONFIG_DYNAMIC_DEBUG`` is not set, ``print_hex_dump_debug()`` is just +shortcut for ``print_hex_dump(KERN_DEBUG)``. + +For ``print_hex_dump_debug()``/``print_hex_dump_bytes()``, format string is +its ``prefix_str`` argument, if it is constant string; or ``hexdump`` +in case ``prefix_str`` is build dynamically. + +Dynamic debug has even more useful features: + + * Simple query language allows turning on and off debugging + statements by matching any combination of 0 or 1 of: + + - source filename + - function name + - line number (including ranges of line numbers) + - module name + - format string + + * Provides a debugfs control file: ``<debugfs>/dynamic_debug/control`` + which can be read to display the complete list of known debug + statements, to help guide you + +Controlling dynamic debug Behaviour +=================================== + +The behaviour of ``pr_debug()``/``dev_dbg()`` are controlled via writing to a +control file in the 'debugfs' filesystem. Thus, you must first mount +the debugfs filesystem, in order to make use of this feature. +Subsequently, we refer to the control file as: +``<debugfs>/dynamic_debug/control``. For example, if you want to enable +printing from source file ``svcsock.c``, line 1603 you simply do:: + + nullarbor:~ # echo 'file svcsock.c line 1603 +p' > + <debugfs>/dynamic_debug/control + +If you make a mistake with the syntax, the write will fail thus:: + + nullarbor:~ # echo 'file svcsock.c wtf 1 +p' > + <debugfs>/dynamic_debug/control + -bash: echo: write error: Invalid argument + +Viewing Dynamic Debug Behaviour +=============================== + +You can view the currently configured behaviour of all the debug +statements via:: + + nullarbor:~ # cat <debugfs>/dynamic_debug/control + # filename:lineno [module]function flags format + /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:323 [svcxprt_rdma]svc_rdma_cleanup =_ "SVCRDMA Module Removed, deregister RPC RDMA transport\012" + /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:341 [svcxprt_rdma]svc_rdma_init =_ "\011max_inline : %d\012" + /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:340 [svcxprt_rdma]svc_rdma_init =_ "\011sq_depth : %d\012" + /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:338 [svcxprt_rdma]svc_rdma_init =_ "\011max_requests : %d\012" + ... + + +You can also apply standard Unix text manipulation filters to this +data, e.g.:: + + nullarbor:~ # grep -i rdma <debugfs>/dynamic_debug/control | wc -l + 62 + + nullarbor:~ # grep -i tcp <debugfs>/dynamic_debug/control | wc -l + 42 + +The third column shows the currently enabled flags for each debug +statement callsite (see below for definitions of the flags). The +default value, with no flags enabled, is ``=_``. So you can view all +the debug statement callsites with any non-default flags:: + + nullarbor:~ # awk '$3 != "=_"' <debugfs>/dynamic_debug/control + # filename:lineno [module]function flags format + /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c:1603 [sunrpc]svc_send p "svc_process: st_sendto returned %d\012" + +Command Language Reference +========================== + +At the lexical level, a command comprises a sequence of words separated +by spaces or tabs. So these are all equivalent:: + + nullarbor:~ # echo -c 'file svcsock.c line 1603 +p' > + <debugfs>/dynamic_debug/control + nullarbor:~ # echo -c ' file svcsock.c line 1603 +p ' > + <debugfs>/dynamic_debug/control + nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > + <debugfs>/dynamic_debug/control + +Command submissions are bounded by a write() system call. +Multiple commands can be written together, separated by ``;`` or ``\n``:: + + ~# echo "func pnpacpi_get_resources +p; func pnp_assign_mem +p" \ + > <debugfs>/dynamic_debug/control + +If your query set is big, you can batch them too:: + + ~# cat query-batch-file > <debugfs>/dynamic_debug/control + +A another way is to use wildcard. The match rule support ``*`` (matches +zero or more characters) and ``?`` (matches exactly one character).For +example, you can match all usb drivers:: + + ~# echo "file drivers/usb/* +p" > <debugfs>/dynamic_debug/control + +At the syntactical level, a command comprises a sequence of match +specifications, followed by a flags change specification:: + + command ::= match-spec* flags-spec + +The match-spec's are used to choose a subset of the known pr_debug() +callsites to which to apply the flags-spec. Think of them as a query +with implicit ANDs between each pair. Note that an empty list of +match-specs will select all debug statement callsites. + +A match specification comprises a keyword, which controls the +attribute of the callsite to be compared, and a value to compare +against. Possible keywords are::: + + match-spec ::= 'func' string | + 'file' string | + 'module' string | + 'format' string | + 'line' line-range + + line-range ::= lineno | + '-'lineno | + lineno'-' | + lineno'-'lineno + + lineno ::= unsigned-int + +.. note:: + + ``line-range`` cannot contain space, e.g. + "1-30" is valid range but "1 - 30" is not. + + +The meanings of each keyword are: + +func + The given string is compared against the function name + of each callsite. Example:: + + func svc_tcp_accept + +file + The given string is compared against either the full pathname, the + src-root relative pathname, or the basename of the source file of + each callsite. Examples:: + + file svcsock.c + file kernel/freezer.c + file /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c + +module + The given string is compared against the module name + of each callsite. The module name is the string as + seen in ``lsmod``, i.e. without the directory or the ``.ko`` + suffix and with ``-`` changed to ``_``. Examples:: + + module sunrpc + module nfsd + +format + The given string is searched for in the dynamic debug format + string. Note that the string does not need to match the + entire format, only some part. Whitespace and other + special characters can be escaped using C octal character + escape ``\ooo`` notation, e.g. the space character is ``\040``. + Alternatively, the string can be enclosed in double quote + characters (``"``) or single quote characters (``'``). + Examples:: + + format svcrdma: // many of the NFS/RDMA server pr_debugs + format readahead // some pr_debugs in the readahead cache + format nfsd:\040SETATTR // one way to match a format with whitespace + format "nfsd: SETATTR" // a neater way to match a format with whitespace + format 'nfsd: SETATTR' // yet another way to match a format with whitespace + +line + The given line number or range of line numbers is compared + against the line number of each ``pr_debug()`` callsite. A single + line number matches the callsite line number exactly. A + range of line numbers matches any callsite between the first + and last line number inclusive. An empty first number means + the first line in the file, an empty line number means the + last number in the file. Examples:: + + line 1603 // exactly line 1603 + line 1600-1605 // the six lines from line 1600 to line 1605 + line -1605 // the 1605 lines from line 1 to line 1605 + line 1600- // all lines from line 1600 to the end of the file + +The flags specification comprises a change operation followed +by one or more flag characters. The change operation is one +of the characters:: + + - remove the given flags + + add the given flags + = set the flags to the given flags + +The flags are:: + + p enables the pr_debug() callsite. + f Include the function name in the printed message + l Include line number in the printed message + m Include module name in the printed message + t Include thread ID in messages not generated from interrupt context + _ No flags are set. (Or'd with others on input) + +For ``print_hex_dump_debug()`` and ``print_hex_dump_bytes()``, only ``p`` flag +have meaning, other flags ignored. + +For display, the flags are preceded by ``=`` +(mnemonic: what the flags are currently equal to). + +Note the regexp ``^[-+=][flmpt_]+$`` matches a flags specification. +To clear all flags at once, use ``=_`` or ``-flmpt``. + + +Debug messages during Boot Process +================================== + +To activate debug messages for core code and built-in modules during +the boot process, even before userspace and debugfs exists, use +``dyndbg="QUERY"``, ``module.dyndbg="QUERY"``, or ``ddebug_query="QUERY"`` +(``ddebug_query`` is obsoleted by ``dyndbg``, and deprecated). QUERY follows +the syntax described above, but must not exceed 1023 characters. Your +bootloader may impose lower limits. + +These ``dyndbg`` params are processed just after the ddebug tables are +processed, as part of the arch_initcall. Thus you can enable debug +messages in all code run after this arch_initcall via this boot +parameter. + +On an x86 system for example ACPI enablement is a subsys_initcall and:: + + dyndbg="file ec.c +p" + +will show early Embedded Controller transactions during ACPI setup if +your machine (typically a laptop) has an Embedded Controller. +PCI (or other devices) initialization also is a hot candidate for using +this boot parameter for debugging purposes. + +If ``foo`` module is not built-in, ``foo.dyndbg`` will still be processed at +boot time, without effect, but will be reprocessed when module is +loaded later. ``dyndbg_query=`` and bare ``dyndbg=`` are only processed at +boot. + + +Debug Messages at Module Initialization Time +============================================ + +When ``modprobe foo`` is called, modprobe scans ``/proc/cmdline`` for +``foo.params``, strips ``foo.``, and passes them to the kernel along with +params given in modprobe args or ``/etc/modprob.d/*.conf`` files, +in the following order: + +1. parameters given via ``/etc/modprobe.d/*.conf``:: + + options foo dyndbg=+pt + options foo dyndbg # defaults to +p + +2. ``foo.dyndbg`` as given in boot args, ``foo.`` is stripped and passed:: + + foo.dyndbg=" func bar +p; func buz +mp" + +3. args to modprobe:: + + modprobe foo dyndbg==pmf # override previous settings + +These ``dyndbg`` queries are applied in order, with last having final say. +This allows boot args to override or modify those from ``/etc/modprobe.d`` +(sensible, since 1 is system wide, 2 is kernel or boot specific), and +modprobe args to override both. + +In the ``foo.dyndbg="QUERY"`` form, the query must exclude ``module foo``. +``foo`` is extracted from the param-name, and applied to each query in +``QUERY``, and only 1 match-spec of each type is allowed. + +The ``dyndbg`` option is a "fake" module parameter, which means: + +- modules do not need to define it explicitly +- every module gets it tacitly, whether they use pr_debug or not +- it doesn't appear in ``/sys/module/$module/parameters/`` + To see it, grep the control file, or inspect ``/proc/cmdline.`` + +For ``CONFIG_DYNAMIC_DEBUG`` kernels, any settings given at boot-time (or +enabled by ``-DDEBUG`` flag during compilation) can be disabled later via +the sysfs interface if the debug messages are no longer needed:: + + echo "module module_name -p" > <debugfs>/dynamic_debug/control + +Examples +======== + +:: + + // enable the message at line 1603 of file svcsock.c + nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > + <debugfs>/dynamic_debug/control + + // enable all the messages in file svcsock.c + nullarbor:~ # echo -n 'file svcsock.c +p' > + <debugfs>/dynamic_debug/control + + // enable all the messages in the NFS server module + nullarbor:~ # echo -n 'module nfsd +p' > + <debugfs>/dynamic_debug/control + + // enable all 12 messages in the function svc_process() + nullarbor:~ # echo -n 'func svc_process +p' > + <debugfs>/dynamic_debug/control + + // disable all 12 messages in the function svc_process() + nullarbor:~ # echo -n 'func svc_process -p' > + <debugfs>/dynamic_debug/control + + // enable messages for NFS calls READ, READLINK, READDIR and READDIR+. + nullarbor:~ # echo -n 'format "nfsd: READ" +p' > + <debugfs>/dynamic_debug/control + + // enable messages in files of which the paths include string "usb" + nullarbor:~ # echo -n '*usb* +p' > <debugfs>/dynamic_debug/control + + // enable all messages + nullarbor:~ # echo -n '+p' > <debugfs>/dynamic_debug/control + + // add module, function to all enabled messages + nullarbor:~ # echo -n '+mf' > <debugfs>/dynamic_debug/control + + // boot-args example, with newlines and comments for readability + Kernel command line: ... + // see whats going on in dyndbg=value processing + dynamic_debug.verbose=1 + // enable pr_debugs in 2 builtins, #cmt is stripped + dyndbg="module params +p #cmt ; module sys +p" + // enable pr_debugs in 2 functions in a module loaded later + pc87360.dyndbg="func pc87360_init_device +p; func pc87360_find +p" diff --git a/Documentation/admin-guide/index.rst b/Documentation/admin-guide/index.rst new file mode 100644 index 0000000..4e5abbb --- /dev/null +++ b/Documentation/admin-guide/index.rst @@ -0,0 +1,34 @@ +Linux Kernel User's Documentation +================================= + +Contents: + +.. toctree:: + :maxdepth: 2 + :numbered: + + README + reporting-bugs + bug-hunting + oops-tracing + ramoops + initrd + init + dynamic-debug-howto + security-bugs + kernel-parameters + serial-console + braille-console + parport + md + module-signing + sysrq + unicode + vga-softcursor + sysfs-rules + devices + binfmt-misc + mono + java + bad-memory + basic-profiling diff --git a/Documentation/init.txt b/Documentation/admin-guide/init.rst index 535ad5e..e89d97f 100644 --- a/Documentation/init.txt +++ b/Documentation/admin-guide/init.rst @@ -5,6 +5,7 @@ OK, so you've got this pretty unintuitive message (currently located in init/main.c) and are wondering what the H*** went wrong. Some high-level reasons for failure (listed roughly in order of execution) to load the init binary are: + A) Unable to mount root FS B) init binary doesn't exist on rootfs C) broken console device @@ -12,37 +13,39 @@ D) binary exists but dependencies not available E) binary cannot be loaded Detailed explanations: -0) Set "debug" kernel parameter (in bootloader config file or CONFIG_CMDLINE) + +A) Set "debug" kernel parameter (in bootloader config file or CONFIG_CMDLINE) to get more detailed kernel messages. -A) make sure you have the correct root FS type - (and root= kernel parameter points to the correct partition), +B) make sure you have the correct root FS type + (and ``root=`` kernel parameter points to the correct partition), required drivers such as storage hardware (such as SCSI or USB!) and filesystem (ext3, jffs2 etc.) are builtin (alternatively as modules, to be pre-loaded by an initrd) -C) Possibly a conflict in console= setup --> initial console unavailable. +C) Possibly a conflict in ``console= setup`` --> initial console unavailable. E.g. some serial consoles are unreliable due to serial IRQ issues (e.g. missing interrupt-based configuration). - Try using a different console= device or e.g. netconsole= . + Try using a different ``console= device`` or e.g. ``netconsole=``. D) e.g. required library dependencies of the init binary such as - /lib/ld-linux.so.2 missing or broken. Use readelf -d <INIT>|grep NEEDED - to find out which libraries are required. + ``/lib/ld-linux.so.2`` missing or broken. Use + ``readelf -d <INIT>|grep NEEDED`` to find out which libraries are required. E) make sure the binary's architecture matches your hardware. E.g. i386 vs. x86_64 mismatch, or trying to load x86 on ARM hardware. In case you tried loading a non-binary file here (shell script?), you should make sure that the script specifies an interpreter in its shebang - header line (#!/...) that is fully working (including its library + header line (``#!/...``) that is fully working (including its library dependencies). And before tackling scripts, better first test a simple - non-script binary such as /bin/sh and confirm its successful execution. - To find out more, add code to init/main.c to display kernel_execve()s + non-script binary such as ``/bin/sh`` and confirm its successful execution. + To find out more, add code ``to init/main.c`` to display kernel_execve()s return values. Please extend this explanation whenever you find new failure causes (after all loading the init binary is a CRITICAL and hard transition step which needs to be made as painless as possible), then submit patch to LKML. Further TODOs: -- Implement the various run_init_process() invocations via a struct array - which can then store the kernel_execve() result value and on failure - log it all by iterating over _all_ results (very important usability fix). + +- Implement the various ``run_init_process()`` invocations via a struct array + which can then store the ``kernel_execve()`` result value and on failure + log it all by iterating over **all** results (very important usability fix). - try to make the implementation itself more helpful in general, e.g. by providing additional error messages at affected places. diff --git a/Documentation/initrd.txt b/Documentation/admin-guide/initrd.rst index 4e1839c..a03daba 100644 --- a/Documentation/initrd.txt +++ b/Documentation/admin-guide/initrd.rst @@ -2,7 +2,7 @@ Using the initial RAM disk (initrd) =================================== Written 1996,2000 by Werner Almesberger <werner.almesberger@epfl.ch> and - Hans Lermen <lermen@fgan.de> +Hans Lermen <lermen@fgan.de> initrd provides the capability to load a RAM disk by the boot loader. @@ -16,7 +16,7 @@ where the kernel comes up with a minimum set of compiled-in drivers, and where additional modules are loaded from initrd. This document gives a brief overview of the use of initrd. A more detailed -discussion of the boot process can be found in [1]. +discussion of the boot process can be found in [#f1]_. Operation @@ -27,10 +27,10 @@ When using initrd, the system typically boots as follows: 1) the boot loader loads the kernel and the initial RAM disk 2) the kernel converts initrd into a "normal" RAM disk and frees the memory used by initrd - 3) if the root device is not /dev/ram0, the old (deprecated) + 3) if the root device is not ``/dev/ram0``, the old (deprecated) change_root procedure is followed. see the "Obsolete root change mechanism" section below. - 4) root device is mounted. if it is /dev/ram0, the initrd image is + 4) root device is mounted. if it is ``/dev/ram0``, the initrd image is then mounted as root 5) /sbin/init is executed (this can be any valid executable, including shell scripts; it is run with uid 0 and can do basically everything @@ -38,7 +38,7 @@ When using initrd, the system typically boots as follows: 6) init mounts the "real" root file system 7) init places the root file system at the root directory using the pivot_root system call - 8) init execs the /sbin/init on the new root filesystem, performing + 8) init execs the ``/sbin/init`` on the new root filesystem, performing the usual boot sequence 9) the initrd file system is removed @@ -51,7 +51,7 @@ be accessible. Boot command-line options ------------------------- -initrd adds the following new options: +initrd adds the following new options:: initrd=<path> (e.g. LOADLIN) @@ -83,36 +83,36 @@ Recent kernels have support for populating a ramdisk from a compressed cpio archive. On such systems, the creation of a ramdisk image doesn't need to involve special block devices or loopbacks; you merely create a directory on disk with the desired initrd content, cd to that directory, and run (as an -example): +example):: -find . | cpio --quiet -H newc -o | gzip -9 -n > /boot/imagefile.img + find . | cpio --quiet -H newc -o | gzip -9 -n > /boot/imagefile.img -Examining the contents of an existing image file is just as simple: +Examining the contents of an existing image file is just as simple:: -mkdir /tmp/imagefile -cd /tmp/imagefile -gzip -cd /boot/imagefile.img | cpio -imd --quiet + mkdir /tmp/imagefile + cd /tmp/imagefile + gzip -cd /boot/imagefile.img | cpio -imd --quiet Installation ------------ First, a directory for the initrd file system has to be created on the -"normal" root file system, e.g. +"normal" root file system, e.g.:: -# mkdir /initrd + # mkdir /initrd -The name is not relevant. More details can be found on the pivot_root(2) -man page. +The name is not relevant. More details can be found on the +:manpage:`pivot_root(2)` man page. If the root file system is created during the boot procedure (i.e. if you're building an install floppy), the root file system creation -procedure should create the /initrd directory. +procedure should create the ``/initrd`` directory. If initrd will not be mounted in some cases, its content is still -accessible if the following device has been created: +accessible if the following device has been created:: -# mknod /dev/initrd b 1 250 -# chmod 400 /dev/initrd + # mknod /dev/initrd b 1 250 + # chmod 400 /dev/initrd Second, the kernel has to be compiled with RAM disk support and with support for the initial RAM disk enabled. Also, at least all components @@ -131,60 +131,76 @@ kernels, at least three types of devices are suitable for that: We'll describe the loopback device method: 1) make sure loopback block devices are configured into the kernel - 2) create an empty file system of the appropriate size, e.g. - # dd if=/dev/zero of=initrd bs=300k count=1 - # mke2fs -F -m0 initrd + 2) create an empty file system of the appropriate size, e.g.:: + + # dd if=/dev/zero of=initrd bs=300k count=1 + # mke2fs -F -m0 initrd + (if space is critical, you may want to use the Minix FS instead of Ext2) - 3) mount the file system, e.g. - # mount -t ext2 -o loop initrd /mnt - 4) create the console device: + 3) mount the file system, e.g.:: + + # mount -t ext2 -o loop initrd /mnt + + 4) create the console device:: + # mkdir /mnt/dev # mknod /mnt/dev/console c 5 1 + 5) copy all the files that are needed to properly use the initrd - environment. Don't forget the most important file, /sbin/init - Note that /sbin/init's permissions must include "x" (execute). + environment. Don't forget the most important file, ``/sbin/init`` + + .. note:: ``/sbin/init`` permissions must include "x" (execute). + 6) correct operation the initrd environment can frequently be tested - even without rebooting with the command - # chroot /mnt /sbin/init + even without rebooting with the command:: + + # chroot /mnt /sbin/init + This is of course limited to initrds that do not interfere with the general system state (e.g. by reconfiguring network interfaces, overwriting mounted devices, trying to start already running demons, etc. Note however that it is usually possible to use pivot_root in such a chroot'ed initrd environment.) - 7) unmount the file system - # umount /mnt + 7) unmount the file system:: + + # umount /mnt + 8) the initrd is now in the file "initrd". Optionally, it can now be - compressed - # gzip -9 initrd + compressed:: + + # gzip -9 initrd For experimenting with initrd, you may want to take a rescue floppy and -only add a symbolic link from /sbin/init to /bin/sh. Alternatively, you -can try the experimental newlib environment [2] to create a small +only add a symbolic link from ``/sbin/init`` to ``/bin/sh``. Alternatively, you +can try the experimental newlib environment [#f2]_ to create a small initrd. Finally, you have to boot the kernel and load initrd. Almost all Linux boot loaders support initrd. Since the boot process is still compatible with an older mechanism, the following boot command line parameters -have to be given: +have to be given:: root=/dev/ram0 rw (rw is only necessary if writing to the initrd file system.) -With LOADLIN, you simply execute +With LOADLIN, you simply execute:: LOADLIN <kernel> initrd=<disk_image> -e.g. LOADLIN C:\LINUX\BZIMAGE initrd=C:\LINUX\INITRD.GZ root=/dev/ram0 rw -With LILO, you add the option INITRD=<path> to either the global section -or to the section of the respective kernel in /etc/lilo.conf, and pass -the options using APPEND, e.g. +e.g.:: + + LOADLIN C:\LINUX\BZIMAGE initrd=C:\LINUX\INITRD.GZ root=/dev/ram0 rw + +With LILO, you add the option ``INITRD=<path>`` to either the global section +or to the section of the respective kernel in ``/etc/lilo.conf``, and pass +the options using APPEND, e.g.:: image = /bzImage initrd = /boot/initrd.gz append = "root=/dev/ram0 rw" -and run /sbin/lilo +and run ``/sbin/lilo`` For other boot loaders, please refer to the respective documentation. @@ -204,33 +220,33 @@ The procedure involves the following steps: - unmounting the initrd file system and de-allocating the RAM disk Mounting the new root file system is easy: it just needs to be mounted on -a directory under the current root. Example: +a directory under the current root. Example:: -# mkdir /new-root -# mount -o ro /dev/hda1 /new-root + # mkdir /new-root + # mount -o ro /dev/hda1 /new-root The root change is accomplished with the pivot_root system call, which -is also available via the pivot_root utility (see pivot_root(8) man -page; pivot_root is distributed with util-linux version 2.10h or higher -[3]). pivot_root moves the current root to a directory under the new +is also available via the ``pivot_root`` utility (see :manpage:`pivot_root(8)` +man page; ``pivot_root`` is distributed with util-linux version 2.10h or higher +[#f3]_). ``pivot_root`` moves the current root to a directory under the new root, and puts the new root at its place. The directory for the old root -must exist before calling pivot_root. Example: +must exist before calling ``pivot_root``. Example:: -# cd /new-root -# mkdir initrd -# pivot_root . initrd + # cd /new-root + # mkdir initrd + # pivot_root . initrd Now, the init process may still access the old root via its executable, shared libraries, standard input/output/error, and its current root directory. All these references are dropped by the -following command: +following command:: -# exec chroot . what-follows <dev/console >dev/console 2>&1 + # exec chroot . what-follows <dev/console >dev/console 2>&1 -Where what-follows is a program under the new root, e.g. /sbin/init +Where what-follows is a program under the new root, e.g. ``/sbin/init`` If the new root file system will be used with udev and has no valid -/dev directory, udev must be initialized before invoking chroot in order -to provide /dev/console. +``/dev`` directory, udev must be initialized before invoking chroot in order +to provide ``/dev/console``. Note: implementation details of pivot_root may change with time. In order to ensure compatibility, the following points should be observed: @@ -244,13 +260,13 @@ to ensure compatibility, the following points should be observed: - use relative paths for dev/console in the exec command Now, the initrd can be unmounted and the memory allocated by the RAM -disk can be freed: +disk can be freed:: -# umount /initrd -# blockdev --flushbufs /dev/ram0 + # umount /initrd + # blockdev --flushbufs /dev/ram0 It is also possible to use initrd with an NFS-mounted root, see the -pivot_root(8) man page for details. +:manpage:`pivot_root(8)` man page for details. Usage scenarios @@ -263,21 +279,21 @@ as follows: 1) system boots from floppy or other media with a minimal kernel (e.g. support for RAM disks, initrd, a.out, and the Ext2 FS) and loads initrd - 2) /sbin/init determines what is needed to (1) mount the "real" root FS + 2) ``/sbin/init`` determines what is needed to (1) mount the "real" root FS (i.e. device type, device drivers, file system) and (2) the distribution media (e.g. CD-ROM, network, tape, ...). This can be done by asking the user, by auto-probing, or by using a hybrid approach. - 3) /sbin/init loads the necessary kernel modules - 4) /sbin/init creates and populates the root file system (this doesn't + 3) ``/sbin/init`` loads the necessary kernel modules + 4) ``/sbin/init`` creates and populates the root file system (this doesn't have to be a very usable system yet) - 5) /sbin/init invokes pivot_root to change the root file system and + 5) ``/sbin/init`` invokes ``pivot_root`` to change the root file system and execs - via chroot - a program that continues the installation 6) the boot loader is installed 7) the boot loader is configured to load an initrd with the set of - modules that was used to bring up the system (e.g. /initrd can be + modules that was used to bring up the system (e.g. ``/initrd`` can be modified, then unmounted, and finally, the image is written from - /dev/ram0 or /dev/rd/0 to a file) + ``/dev/ram0`` or ``/dev/rd/0`` to a file) 8) now the system is bootable and additional installation tasks can be performed @@ -290,7 +306,7 @@ different hardware configurations in a single administrative domain. In such cases, it is desirable to generate only a small set of kernels (ideally only one) and to keep the system-specific part of configuration information as small as possible. In this case, a common initrd could be -generated with all the necessary modules. Then, only /sbin/init or a file +generated with all the necessary modules. Then, only ``/sbin/init`` or a file read by it would have to be different. A third scenario is more convenient recovery disks, because information @@ -301,9 +317,9 @@ auto-detection). Last not least, CD-ROM distributors may use it for better installation from CD, e.g. by using a boot floppy and bootstrapping a bigger RAM disk -via initrd from CD; or by booting via a loader like LOADLIN or directly +via initrd from CD; or by booting via a loader like ``LOADLIN`` or directly from the CD-ROM, and loading the RAM disk from CD without need of -floppies. +floppies. Obsolete root change mechanism @@ -316,51 +332,52 @@ continued availability. It works by mounting the "real" root device (i.e. the one set with rdev in the kernel image or with root=... at the boot command line) as the root file system when linuxrc exits. The initrd file system is then -unmounted, or, if it is still busy, moved to a directory /initrd, if +unmounted, or, if it is still busy, moved to a directory ``/initrd``, if such a directory exists on the new root file system. In order to use this mechanism, you do not have to specify the boot command options root, init, or rw. (If specified, they will affect the real root file system, not the initrd environment.) - + If /proc is mounted, the "real" root device can be changed from within linuxrc by writing the number of the new root FS device to the special -file /proc/sys/kernel/real-root-dev, e.g. +file /proc/sys/kernel/real-root-dev, e.g.:: # echo 0x301 >/proc/sys/kernel/real-root-dev Note that the mechanism is incompatible with NFS and similar file systems. -This old, deprecated mechanism is commonly called "change_root", while -the new, supported mechanism is called "pivot_root". +This old, deprecated mechanism is commonly called ``change_root``, while +the new, supported mechanism is called ``pivot_root``. Mixed change_root and pivot_root mechanism ------------------------------------------ -In case you did not want to use root=/dev/ram0 to trigger the pivot_root -mechanism, you may create both /linuxrc and /sbin/init in your initrd image. +In case you did not want to use ``root=/dev/ram0`` to trigger the pivot_root +mechanism, you may create both ``/linuxrc`` and ``/sbin/init`` in your initrd +image. -/linuxrc would contain only the following: +``/linuxrc`` would contain only the following:: -#! /bin/sh -mount -n -t proc proc /proc -echo 0x0100 >/proc/sys/kernel/real-root-dev -umount -n /proc + #! /bin/sh + mount -n -t proc proc /proc + echo 0x0100 >/proc/sys/kernel/real-root-dev + umount -n /proc Once linuxrc exited, the kernel would mount again your initrd as root, -this time executing /sbin/init. Again, it would be the duty of this init -to build the right environment (maybe using the root= device passed on -the cmdline) before the final execution of the real /sbin/init. +this time executing ``/sbin/init``. Again, it would be the duty of this init +to build the right environment (maybe using the ``root= device`` passed on +the cmdline) before the final execution of the real ``/sbin/init``. Resources --------- -[1] Almesberger, Werner; "Booting Linux: The History and the Future" +.. [#f1] Almesberger, Werner; "Booting Linux: The History and the Future" http://www.almesberger.net/cv/papers/ols2k-9.ps.gz -[2] newlib package (experimental), with initrd example - http://sources.redhat.com/newlib/ -[3] util-linux: Miscellaneous utilities for Linux - http://www.kernel.org/pub/linux/utils/util-linux/ +.. [#f2] newlib package (experimental), with initrd example + https://www.sourceware.org/newlib/ +.. [#f3] util-linux: Miscellaneous utilities for Linux + https://www.kernel.org/pub/linux/utils/util-linux/ diff --git a/Documentation/java.txt b/Documentation/admin-guide/java.rst index 4180205..a0de7c1 100644 --- a/Documentation/java.txt +++ b/Documentation/admin-guide/java.rst @@ -1,5 +1,5 @@ - Java(tm) Binary Kernel Support for Linux v1.03 - ---------------------------------------------- +Java(tm) Binary Kernel Support for Linux v1.03 +---------------------------------------------- Linux beats them ALL! While all other OS's are TALKING about direct support of Java Binaries in the OS, Linux is doing it! @@ -19,70 +19,80 @@ other program after you have done the following: as the application itself). 2) You have to compile BINFMT_MISC either as a module or into - the kernel (CONFIG_BINFMT_MISC) and set it up properly. + the kernel (``CONFIG_BINFMT_MISC``) and set it up properly. If you choose to compile it as a module, you will have to insert it manually with modprobe/insmod, as kmod - cannot easily be supported with binfmt_misc. + cannot easily be supported with binfmt_misc. Read the file 'binfmt_misc.txt' in this directory to know more about the configuration process. 3) Add the following configuration items to binfmt_misc - (you should really have read binfmt_misc.txt now): - support for Java applications: + (you should really have read ``binfmt_misc.txt`` now): + support for Java applications:: + ':Java:M::\xca\xfe\xba\xbe::/usr/local/bin/javawrapper:' - support for executable Jar files: + + support for executable Jar files:: + ':ExecutableJAR:E::jar::/usr/local/bin/jarwrapper:' - support for Java Applets: + + support for Java Applets:: + ':Applet:E::html::/usr/bin/appletviewer:' - or the following, if you want to be more selective: + + or the following, if you want to be more selective:: + ':Applet:M::<!--applet::/usr/bin/appletviewer:' Of course you have to fix the path names. The path/file names given in this - document match the Debian 2.1 system. (i.e. jdk installed in /usr, - custom wrappers from this document in /usr/local) + document match the Debian 2.1 system. (i.e. jdk installed in ``/usr``, + custom wrappers from this document in ``/usr/local``) Note, that for the more selective applet support you have to modify - existing html-files to contain <!--applet--> in the first line - ('<' has to be the first character!) to let this work! + existing html-files to contain ``<!--applet-->`` in the first line + (``<`` has to be the first character!) to let this work! For the compiled Java programs you need a wrapper script like the following (this is because Java is broken in case of the filename handling), again fix the path names, both in the script and in the above given configuration string. - You, too, need the little program after the script. Compile like - gcc -O2 -o javaclassname javaclassname.c - and stick it to /usr/local/bin. + You, too, need the little program after the script. Compile like:: + + gcc -O2 -o javaclassname javaclassname.c + + and stick it to ``/usr/local/bin``. Both the javawrapper shellscript and the javaclassname program were supplied by Colin J. Watson <cjw44@cam.ac.uk>. -====================== Cut here =================== -#!/bin/bash -# /usr/local/bin/javawrapper - the wrapper for binfmt_misc/java +Javawrapper shell script:: -if [ -z "$1" ]; then + #!/bin/bash + # /usr/local/bin/javawrapper - the wrapper for binfmt_misc/java + + if [ -z "$1" ]; then exec 1>&2 echo Usage: $0 class-file exit 1 -fi + fi -CLASS=$1 -FQCLASS=`/usr/local/bin/javaclassname $1` -FQCLASSN=`echo $FQCLASS | sed -e 's/^.*\.\([^.]*\)$/\1/'` -FQCLASSP=`echo $FQCLASS | sed -e 's-\.-/-g' -e 's-^[^/]*$--' -e 's-/[^/]*$--'` + CLASS=$1 + FQCLASS=`/usr/local/bin/javaclassname $1` + FQCLASSN=`echo $FQCLASS | sed -e 's/^.*\.\([^.]*\)$/\1/'` + FQCLASSP=`echo $FQCLASS | sed -e 's-\.-/-g' -e 's-^[^/]*$--' -e 's-/[^/]*$--'` -# for example: -# CLASS=Test.class -# FQCLASS=foo.bar.Test -# FQCLASSN=Test -# FQCLASSP=foo/bar + # for example: + # CLASS=Test.class + # FQCLASS=foo.bar.Test + # FQCLASSN=Test + # FQCLASSP=foo/bar -unset CLASSBASE + unset CLASSBASE -declare -i LINKLEVEL=0 + declare -i LINKLEVEL=0 -while :; do + while :; do if [ "`basename $CLASS .class`" == "$FQCLASSN" ]; then # See if this directory works straight off cd -L `dirname $CLASS` @@ -119,9 +129,9 @@ while :; do exit 1 fi CLASS=`ls --color=no -l $CLASS | sed -e 's/^.* \([^ ]*\)$/\1/'` -done + done -if [ -z "$CLASSBASE" ]; then + if [ -z "$CLASSBASE" ]; then if [ -z "$FQCLASSP" ]; then GOODNAME=$FQCLASSN.class else @@ -131,24 +141,23 @@ if [ -z "$CLASSBASE" ]; then echo $0: echo " $FQCLASS should be in a file called $GOODNAME" exit 1 -fi + fi -if ! echo $CLASSPATH | grep -q "^\(.*:\)*$CLASSBASE\(:.*\)*"; then + if ! echo $CLASSPATH | grep -q "^\(.*:\)*$CLASSBASE\(:.*\)*"; then # class is not in CLASSPATH, so prepend dir of class to CLASSPATH if [ -z "${CLASSPATH}" ] ; then export CLASSPATH=$CLASSBASE else export CLASSPATH=$CLASSBASE:$CLASSPATH fi -fi + fi -shift -/usr/bin/java $FQCLASS "$@" -====================== Cut here =================== + shift + /usr/bin/java $FQCLASS "$@" +javaclassname.c:: -====================== Cut here =================== -/* javaclassname.c + /* javaclassname.c * * Extracts the class name from a Java class file; intended for use in a Java * wrapper of the type supported by the binfmt_misc option in the Linux kernel. @@ -170,57 +179,57 @@ shift * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ -#include <stdlib.h> -#include <stdio.h> -#include <stdarg.h> -#include <sys/types.h> - -/* From Sun's Java VM Specification, as tag entries in the constant pool. */ - -#define CP_UTF8 1 -#define CP_INTEGER 3 -#define CP_FLOAT 4 -#define CP_LONG 5 -#define CP_DOUBLE 6 -#define CP_CLASS 7 -#define CP_STRING 8 -#define CP_FIELDREF 9 -#define CP_METHODREF 10 -#define CP_INTERFACEMETHODREF 11 -#define CP_NAMEANDTYPE 12 -#define CP_METHODHANDLE 15 -#define CP_METHODTYPE 16 -#define CP_INVOKEDYNAMIC 18 - -/* Define some commonly used error messages */ - -#define seek_error() error("%s: Cannot seek\n", program) -#define corrupt_error() error("%s: Class file corrupt\n", program) -#define eof_error() error("%s: Unexpected end of file\n", program) -#define utf8_error() error("%s: Only ASCII 1-255 supported\n", program); - -char *program; - -long *pool; - -u_int8_t read_8(FILE *classfile); -u_int16_t read_16(FILE *classfile); -void skip_constant(FILE *classfile, u_int16_t *cur); -void error(const char *format, ...); -int main(int argc, char **argv); - -/* Reads in an unsigned 8-bit integer. */ -u_int8_t read_8(FILE *classfile) -{ + #include <stdlib.h> + #include <stdio.h> + #include <stdarg.h> + #include <sys/types.h> + + /* From Sun's Java VM Specification, as tag entries in the constant pool. */ + + #define CP_UTF8 1 + #define CP_INTEGER 3 + #define CP_FLOAT 4 + #define CP_LONG 5 + #define CP_DOUBLE 6 + #define CP_CLASS 7 + #define CP_STRING 8 + #define CP_FIELDREF 9 + #define CP_METHODREF 10 + #define CP_INTERFACEMETHODREF 11 + #define CP_NAMEANDTYPE 12 + #define CP_METHODHANDLE 15 + #define CP_METHODTYPE 16 + #define CP_INVOKEDYNAMIC 18 + + /* Define some commonly used error messages */ + + #define seek_error() error("%s: Cannot seek\n", program) + #define corrupt_error() error("%s: Class file corrupt\n", program) + #define eof_error() error("%s: Unexpected end of file\n", program) + #define utf8_error() error("%s: Only ASCII 1-255 supported\n", program); + + char *program; + + long *pool; + + u_int8_t read_8(FILE *classfile); + u_int16_t read_16(FILE *classfile); + void skip_constant(FILE *classfile, u_int16_t *cur); + void error(const char *format, ...); + int main(int argc, char **argv); + + /* Reads in an unsigned 8-bit integer. */ + u_int8_t read_8(FILE *classfile) + { int b = fgetc(classfile); if(b == EOF) eof_error(); return (u_int8_t)b; -} + } -/* Reads in an unsigned 16-bit integer. */ -u_int16_t read_16(FILE *classfile) -{ + /* Reads in an unsigned 16-bit integer. */ + u_int16_t read_16(FILE *classfile) + { int b1, b2; b1 = fgetc(classfile); if(b1 == EOF) @@ -229,11 +238,11 @@ u_int16_t read_16(FILE *classfile) if(b2 == EOF) eof_error(); return (u_int16_t)((b1 << 8) | b2); -} + } -/* Reads in a value from the constant pool. */ -void skip_constant(FILE *classfile, u_int16_t *cur) -{ + /* Reads in a value from the constant pool. */ + void skip_constant(FILE *classfile, u_int16_t *cur) + { u_int16_t len; int seekerr = 1; pool[*cur] = ftell(classfile); @@ -270,19 +279,19 @@ void skip_constant(FILE *classfile, u_int16_t *cur) } if(seekerr) seek_error(); -} + } -void error(const char *format, ...) -{ + void error(const char *format, ...) + { va_list ap; va_start(ap, format); vfprintf(stderr, format, ap); va_end(ap); exit(1); -} + } -int main(int argc, char **argv) -{ + int main(int argc, char **argv) + { FILE *classfile; u_int16_t cp_count, i, this_class, classinfo_ptr; u_int8_t length; @@ -349,19 +358,19 @@ int main(int argc, char **argv) free(pool); fclose(classfile); return 0; -} -====================== Cut here =================== + } + +jarwrapper:: + #!/bin/bash + # /usr/local/java/bin/jarwrapper - the wrapper for binfmt_misc/jar -====================== Cut here =================== -#!/bin/bash -# /usr/local/java/bin/jarwrapper - the wrapper for binfmt_misc/jar + java -jar $1 -java -jar $1 -====================== Cut here =================== +Now simply ``chmod +x`` the ``.class``, ``.jar`` and/or ``.html`` files you +want to execute. -Now simply chmod +x the .class, .jar and/or .html files you want to execute. To add a Java program to your path best put a symbolic link to the main .class file into /usr/bin (or another place you like) omitting the .class extension. The directory containing the original .class file will be @@ -369,7 +378,7 @@ added to your CLASSPATH during execution. To test your new setup, enter in the following simple Java app, and name -it "HelloWorld.java": +it "HelloWorld.java":: class HelloWorld { public static void main(String args[]) { @@ -377,23 +386,28 @@ it "HelloWorld.java": } } -Now compile the application with: +Now compile the application with:: + javac HelloWorld.java -Set the executable permissions of the binary file, with: +Set the executable permissions of the binary file, with:: + chmod 755 HelloWorld.class -And then execute it: +And then execute it:: + ./HelloWorld.class -To execute Java Jar files, simple chmod the *.jar files to include -the execution bit, then just do +To execute Java Jar files, simple chmod the ``*.jar`` files to include +the execution bit, then just do:: + ./Application.jar -To execute Java Applets, simple chmod the *.html files to include -the execution bit, then just do +To execute Java Applets, simple chmod the ``*.html`` files to include +the execution bit, then just do:: + ./Applet.html @@ -401,4 +415,3 @@ originally by Brian A. Lantz, brian@lantz.com heavily edited for binfmt_misc by Richard Günther new scripts by Colin J. Watson <cjw44@cam.ac.uk> added executable Jar file support by Kurt Huwig <kurt@iku-netz.de> - diff --git a/Documentation/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.rst index 37babf9..d2f2725 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.rst @@ -1,5 +1,5 @@ - Kernel Parameters - ~~~~~~~~~~~~~~~~~ +Kernel Parameters +~~~~~~~~~~~~~~~~~ The following is a consolidated list of the kernel parameters as implemented by the __setup(), core_param() and module_param() macros @@ -14,7 +14,7 @@ environment, others are passed as command line arguments to init. Everything after "--" is passed as an argument to init. Module parameters can be specified in two ways: via the kernel command -line with a module name prefix, or via modprobe, e.g.: +line with a module name prefix, or via modprobe, e.g.:: (kernel command line) usbcore.blinkenlights=1 (modprobe command line) modprobe usbcore blinkenlights=1 @@ -25,12 +25,16 @@ kernel command line (/proc/cmdline) and collects module parameters when it loads a module, so the kernel command line can be used for loadable modules too. -Hyphens (dashes) and underscores are equivalent in parameter names, so +Hyphens (dashes) and underscores are equivalent in parameter names, so:: + log_buf_len=1M print-fatal-signals=1 -can also be entered as + +can also be entered as:: + log-buf-len=1M print_fatal_signals=1 -Double-quotes can be used to protect spaces in values, e.g.: +Double-quotes can be used to protect spaces in values, e.g.:: + param="spaces in here" cpu lists: @@ -69,12 +73,12 @@ This document may not be entirely up to date and comprehensive. The command module. Loadable modules, after being loaded into the running kernel, also reveal their parameters in /sys/module/${modulename}/parameters/. Some of these parameters may be changed at runtime by the command -"echo -n ${value} > /sys/module/${modulename}/parameters/${parm}". +``echo -n ${value} > /sys/module/${modulename}/parameters/${parm}``. The parameters listed below are only valid if certain kernel build options were enabled and if respective hardware is present. The text in square brackets at the beginning of each description states the restrictions within which a -parameter is applicable: +parameter is applicable:: ACPI ACPI support is enabled. AGP AGP (Accelerated Graphics Port) is enabled. @@ -165,7 +169,7 @@ parameter is applicable: X86_UV SGI UV support is enabled. XEN Xen support is enabled -In addition, the following text indicates that the option: +In addition, the following text indicates that the option:: BUGS= Relates to possible processor bugs on the said processor. KNL Is a kernel start-up parameter. @@ -194,7 +198,7 @@ and is between 256 and 4096 characters. It is defined in the file Finally, the [KMG] suffix is commonly described after a number of kernel parameter values. These 'K', 'M', and 'G' letters represent the _binary_ multipliers 'Kilo', 'Mega', and 'Giga', equalling 2^10, 2^20, and 2^30 -bytes respectively. Such letter suffixes can also be entirely omitted. +bytes respectively. Such letter suffixes can also be entirely omitted:: acpi= [HW,ACPI,X86,ARM64] @@ -811,7 +815,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. bits, and "f" is flow control ("r" for RTS or omit it). Default is "9600n8". - See Documentation/serial-console.txt for more + See Documentation/admin-guide/serial-console.rst for more information. See Documentation/networking/netconsole.txt for an alternative. @@ -2235,7 +2239,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. mce=option [X86-64] See Documentation/x86/x86_64/boot-options.txt md= [HW] RAID subsystems devices and level - See Documentation/md.txt. + See Documentation/admin-guide/md.rst. mdacon= [MDA] Format: <first>,<last> @@ -2545,7 +2549,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. will be sent. The default is to send the implementation identification information. - + nfs.recover_lost_locks = [NFSv4] Attempt to recover locks that were lost due to a lease timeout on the server. Please note that @@ -3318,7 +3322,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. r128= [HW,DRM] raid= [HW,RAID] - See Documentation/md.txt. + See Documentation/admin-guide/md.rst. ramdisk_size= [RAM] Sizes of RAM disks in kilobytes See Documentation/blockdev/ramdisk.txt. @@ -4197,7 +4201,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. See also Documentation/input/joystick-parport.txt udbg-immortal [PPC] When debugging early kernel crashes that - happen after console_init() and before a proper + happen after console_init() and before a proper console driver takes over, this boot options might help "seeing" what's going on. @@ -4565,8 +4569,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Format: <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]] -______________________________________________________________________ +------------------------ -TODO: +Todo +---- Add more DRM drivers. diff --git a/Documentation/md.txt b/Documentation/admin-guide/md.rst index d6e2fcf..e449fb5 100644 --- a/Documentation/md.txt +++ b/Documentation/admin-guide/md.rst @@ -1,42 +1,77 @@ -Tools that manage md devices can be found at - http://www.kernel.org/pub/linux/utils/raid/ - +RAID arrays +=========== Boot time assembly of RAID arrays --------------------------------- +Tools that manage md devices can be found at + http://www.kernel.org/pub/linux/utils/raid/ + + You can boot with your md device with the following kernel command lines: -for old raid arrays without persistent superblocks: +for old raid arrays without persistent superblocks:: + md=<md device no.>,<raid level>,<chunk size factor>,<fault level>,dev0,dev1,...,devn -for raid arrays with persistent superblocks +for raid arrays with persistent superblocks:: + md=<md device no.>,dev0,dev1,...,devn -or, to assemble a partitionable array: + +or, to assemble a partitionable array:: + md=d<md device no.>,dev0,dev1,...,devn - -md device no. = the number of the md device ... - 0 means md0, - 1 md1, - 2 md2, - 3 md3, - 4 md4 - -raid level = -1 linear mode - 0 striped mode - other modes are only supported with persistent super blocks - -chunk size factor = (raid-0 and raid-1 only) - Set the chunk size as 4k << n. - -fault level = totally ignored - -dev0-devn: e.g. /dev/hda1,/dev/hdc1,/dev/sda1,/dev/sdb1 - -A possible loadlin line (Harald Hoyer <HarryH@Royal.Net>) looks like this: - -e:\loadlin\loadlin e:\zimage root=/dev/md0 md=0,0,4,0,/dev/hdb2,/dev/hdc3 ro + +``md device no.`` ++++++++++++++++++ + +The number of the md device + +================= ========= +``md device no.`` device +================= ========= + 0 md0 + 1 md1 + 2 md2 + 3 md3 + 4 md4 +================= ========= + +``raid level`` +++++++++++++++ + +level of the RAID array + +=============== ============= +``raid level`` level +=============== ============= +-1 linear mode +0 striped mode +=============== ============= + +other modes are only supported with persistent super blocks + +``chunk size factor`` ++++++++++++++++++++++ + +(raid-0 and raid-1 only) + +Set the chunk size as 4k << n. + +``fault level`` ++++++++++++++++ + +Totally ignored + +``dev0`` to ``devn`` +++++++++++++++++++++ + +e.g. ``/dev/hda1``, ``/dev/hdc1``, ``/dev/sda1``, ``/dev/sdb1`` + +A possible loadlin line (Harald Hoyer <HarryH@Royal.Net>) looks like this:: + + e:\loadlin\loadlin e:\zimage root=/dev/md0 md=0,0,4,0,/dev/hdb2,/dev/hdc3 ro Boot time autodetection of RAID arrays @@ -45,10 +80,10 @@ Boot time autodetection of RAID arrays When md is compiled into the kernel (not as module), partitions of type 0xfd are scanned and automatically assembled into RAID arrays. This autodetection may be suppressed with the kernel parameter -"raid=noautodetect". As of kernel 2.6.9, only drives with a type 0 +``raid=noautodetect``. As of kernel 2.6.9, only drives with a type 0 superblock can be autodetected and run at boot time. -The kernel parameter "raid=partitionable" (or "raid=part") means +The kernel parameter ``raid=partitionable`` (or ``raid=part``) means that all auto-detected arrays are assembled as partitionable. Boot time assembly of degraded/dirty arrays @@ -56,22 +91,23 @@ Boot time assembly of degraded/dirty arrays If a raid5 or raid6 array is both dirty and degraded, it could have undetectable data corruption. This is because the fact that it is -'dirty' means that the parity cannot be trusted, and the fact that it +``dirty`` means that the parity cannot be trusted, and the fact that it is degraded means that some datablocks are missing and cannot reliably be reconstructed (due to no parity). For this reason, md will normally refuse to start such an array. This requires the sysadmin to take action to explicitly start the array -despite possible corruption. This is normally done with +despite possible corruption. This is normally done with:: + mdadm --assemble --force .... This option is not really available if the array has the root filesystem on it. In order to support this booting from such an -array, md supports a module parameter "start_dirty_degraded" which, +array, md supports a module parameter ``start_dirty_degraded`` which, when set to 1, bypassed the checks and will allows dirty degraded arrays to be started. -So, to boot with a root filesystem of a dirty degraded raid[56], use +So, to boot with a root filesystem of a dirty degraded raid 5 or 6, use:: md-mod.start_dirty_degraded=1 @@ -80,30 +116,30 @@ Superblock formats ------------------ The md driver can support a variety of different superblock formats. -Currently, it supports superblock formats "0.90.0" and the "md-1" format +Currently, it supports superblock formats ``0.90.0`` and the ``md-1`` format introduced in the 2.5 development series. The kernel will autodetect which format superblock is being used. -Superblock format '0' is treated differently to others for legacy +Superblock format ``0`` is treated differently to others for legacy reasons - it is the original superblock format. General Rules - apply for all superblock formats ------------------------------------------------ -An array is 'created' by writing appropriate superblocks to all +An array is ``created`` by writing appropriate superblocks to all devices. -It is 'assembled' by associating each of these devices with an +It is ``assembled`` by associating each of these devices with an particular md virtual device. Once it is completely assembled, it can be accessed. An array should be created by a user-space tool. This will write superblocks to all devices. It will usually mark the array as -'unclean', or with some devices missing so that the kernel md driver -can create appropriate redundancy (copying in raid1, parity -calculation in raid4/5). +``unclean``, or with some devices missing so that the kernel md driver +can create appropriate redundancy (copying in raid 1, parity +calculation in raid 4/5). When an array is assembled, it is first initialized with the SET_ARRAY_INFO ioctl. This contains, in particular, a major and minor @@ -126,13 +162,12 @@ Devices that have failed or are not yet active can be detached from an array using HOT_REMOVE_DISK. -Specific Rules that apply to format-0 super block arrays, and - arrays with no superblock (non-persistent). -------------------------------------------------------------- +Specific Rules that apply to format-0 super block arrays, and arrays with no superblock (non-persistent) +-------------------------------------------------------------------------------------------------------- -An array can be 'created' by describing the array (level, chunksize -etc) in a SET_ARRAY_INFO ioctl. This must have major_version==0 and -raid_disks != 0. +An array can be ``created`` by describing the array (level, chunksize +etc) in a SET_ARRAY_INFO ioctl. This must have ``major_version==0`` and +``raid_disks != 0``. Then uninitialized devices can be added with ADD_NEW_DISK. The structure passed to ADD_NEW_DISK must specify the state of the device @@ -142,24 +177,26 @@ Once started with RUN_ARRAY, uninitialized spares can be added with HOT_ADD_DISK. - MD devices in sysfs ------------------- -md devices appear in sysfs (/sys) as regular block devices, -e.g. + +md devices appear in sysfs (``/sys``) as regular block devices, +e.g.:: + /sys/block/md0 -Each 'md' device will contain a subdirectory called 'md' which +Each ``md`` device will contain a subdirectory called ``md`` which contains further md-specific information about the device. All md devices contain: + level - a text file indicating the 'raid level'. e.g. raid0, raid1, + a text file indicating the ``raid level``. e.g. raid0, raid1, raid5, linear, multipath, faulty. If no raid level has been set yet (array is still being assembled), the value will reflect whatever has been written to it, which may be a name like the above, or may be a number - such as '0', '5', etc. + such as ``0``, ``5``, etc. raid_disks a text file with a simple number indicating the number of devices @@ -172,10 +209,10 @@ All md devices contain: A change to this attribute will not be permitted if it would reduce the size of the array. To reduce the number of drives in an e.g. raid5, the array size must first be reduced by - setting the 'array_size' attribute. + setting the ``array_size`` attribute. chunk_size - This is the size in bytes for 'chunks' and is only relevant to + This is the size in bytes for ``chunks`` and is only relevant to raid levels that involve striping (0,4,5,6,10). The address space of the array is conceptually divided into chunks and consecutive chunks are striped onto neighbouring devices. @@ -183,7 +220,7 @@ All md devices contain: of 2. This can only be set while assembling an array layout - The "layout" for the array for the particular level. This is + The ``layout`` for the array for the particular level. This is simply a number that is interpretted differently by different levels. It can be written while assembling an array. @@ -193,22 +230,24 @@ All md devices contain: devices. Writing a number (in Kilobytes) which is less than the available size will set the size. Any reconfiguration of the array (e.g. adding devices) will not cause the size to change. - Writing the word 'default' will cause the effective size of the + Writing the word ``default`` will cause the effective size of the array to be whatever size is actually available based on - 'level', 'chunk_size' and 'component_size'. + ``level``, ``chunk_size`` and ``component_size``. This can be used to reduce the size of the array before reducing the number of devices in a raid4/5/6, or to support external metadata formats which mandate such clipping. reshape_position - This is either "none" or a sector number within the devices of - the array where "reshape" is up to. If this is set, the three + This is either ``none`` or a sector number within the devices of + the array where ``reshape`` is up to. If this is set, the three attributes mentioned above (raid_disks, chunk_size, layout) can potentially have 2 values, an old and a new value. If these - values differ, reading the attribute returns + values differ, reading the attribute returns:: + new (old) - and writing will effect the 'new' value, leaving the 'old' + + and writing will effect the ``new`` value, leaving the ``old`` unchanged. component_size @@ -223,9 +262,9 @@ All md devices contain: metadata_version This indicates the format that is being used to record metadata about the array. It can be 0.90 (traditional format), 1.0, 1.1, - 1.2 (newer format in varying locations) or "none" indicating that + 1.2 (newer format in varying locations) or ``none`` indicating that the kernel isn't managing metadata at all. - Alternately it can be "external:" followed by a string which + Alternately it can be ``external:`` followed by a string which is set by user-space. This indicates that metadata is managed by a user-space program. Any device failure or other event that requires a metadata update will cause array activity to be @@ -233,9 +272,9 @@ All md devices contain: resync_start The point at which resync should start. If no resync is needed, - this will be a very large number (or 'none' since 2.6.30-rc1). At + this will be a very large number (or ``none`` since 2.6.30-rc1). At array creation it will default to 0, though starting the array as - 'clean' will set it much larger. + ``clean`` will set it much larger. new_dev This file can be written but not read. The value written should @@ -246,10 +285,10 @@ All md devices contain: safe_mode_delay When an md array has seen no write requests for a certain period - of time, it will be marked as 'clean'. When another write - request arrives, the array is marked as 'dirty' before the write - commences. This is known as 'safe_mode'. - The 'certain period' is controlled by this file which stores the + of time, it will be marked as ``clean``. When another write + request arrives, the array is marked as ``dirty`` before the write + commences. This is known as ``safe_mode``. + The ``certain period`` is controlled by this file which stores the period as a number of seconds. The default is 200msec (0.200). Writing a value of 0 disables safemode. @@ -260,38 +299,50 @@ All md devices contain: cannot be explicitly set, and some transitions are not allowed. Select/poll works on this file. All changes except between - active_idle and active (which can be frequent and are not - very interesting) are notified. active->active_idle is - reported if the metadata is externally managed. + Active_idle and active (which can be frequent and are not + very interesting) are notified. active->active_idle is + reported if the metadata is externally managed. clear No devices, no size, no level + Writing is equivalent to STOP_ARRAY ioctl + inactive May have some settings, but array is not active - all IO results in error + all IO results in error + When written, doesn't tear down array, but just stops it + suspended (not supported yet) All IO requests will block. The array can be reconfigured. + Writing this, if accepted, will block until array is quiessent + readonly no resync can happen. no superblocks get written. - write requests fail + + Write requests fail + read-auto - like readonly, but behaves like 'clean' on a write request. + like readonly, but behaves like ``clean`` on a write request. + + clean + no pending writes, but otherwise active. - clean - no pending writes, but otherwise active. When written to inactive array, starts without resync + If a write request arrives then - if metadata is known, mark 'dirty' and switch to 'active'. - if not known, block and switch to write-pending + if metadata is known, mark ``dirty`` and switch to ``active``. + if not known, block and switch to write-pending + If written to an active array that has pending writes, then fails. active fully active: IO and resync can be happening. When written to inactive array, starts with resync write-pending - clean, but writes are blocked waiting for 'active' to be written. + clean, but writes are blocked waiting for ``active`` to be written. active-idle like active, but no writes have been seen for a while (safe_mode_delay). @@ -299,57 +350,71 @@ All md devices contain: bitmap/location This indicates where the write-intent bitmap for the array is stored. - It can be one of "none", "file" or "[+-]N". - "file" may later be extended to "file:/file/name" - "[+-]N" means that many sectors from the start of the metadata. - This is replicated on all devices. For arrays with externally - managed metadata, the offset is from the beginning of the - device. + + It can be one of ``none``, ``file`` or ``[+-]N``. + ``file`` may later be extended to ``file:/file/name`` + ``[+-]N`` means that many sectors from the start of the metadata. + + This is replicated on all devices. For arrays with externally + managed metadata, the offset is from the beginning of the + device. + bitmap/chunksize The size, in bytes, of the chunk which will be represented by a single bit. For RAID456, it is a portion of an individual device. For RAID10, it is a portion of the array. For RAID1, it is both (they come to the same thing). + bitmap/time_base The time, in seconds, between looking for bits in the bitmap to be cleared. In the current implementation, a bit will be cleared - between 2 and 3 times "time_base" after all the covered blocks + between 2 and 3 times ``time_base`` after all the covered blocks are known to be in-sync. + bitmap/backlog When write-mostly devices are active in a RAID1, write requests to those devices proceed in the background - the filesystem (or other user of the device) does not have to wait for them. - 'backlog' sets a limit on the number of concurrent background + ``backlog`` sets a limit on the number of concurrent background writes. If there are more than this, new writes will by synchronous. + bitmap/metadata - This can be either 'internal' or 'external'. - 'internal' is the default and means the metadata for the bitmap - is stored in the first 256 bytes of the allocated space and is - managed by the md module. - 'external' means that bitmap metadata is managed externally to - the kernel (i.e. by some userspace program) + This can be either ``internal`` or ``external``. + + ``internal`` + is the default and means the metadata for the bitmap + is stored in the first 256 bytes of the allocated space and is + managed by the md module. + + ``external`` + means that bitmap metadata is managed externally to + the kernel (i.e. by some userspace program) + bitmap/can_clear - This is either 'true' or 'false'. If 'true', then bits in the + This is either ``true`` or ``false``. If ``true``, then bits in the bitmap will be cleared when the corresponding blocks are thought - to be in-sync. If 'false', bits will never be cleared. - This is automatically set to 'false' if a write happens on a + to be in-sync. If ``false``, bits will never be cleared. + This is automatically set to ``false`` if a write happens on a degraded array, or if the array becomes degraded during a write. When metadata is managed externally, it should be set to true once the array becomes non-degraded, and this fact has been recorded in the metadata. - - - -As component devices are added to an md array, they appear in the 'md' -directory as new directories named + + + +As component devices are added to an md array, they appear in the ``md`` +directory as new directories named:: + dev-XXX -where XXX is a name that the kernel knows for the device, e.g. hdb1. + +where ``XXX`` is a name that the kernel knows for the device, e.g. hdb1. Each directory contains: block - a symlink to the block device in /sys/block, e.g. + a symlink to the block device in /sys/block, e.g.:: + /sys/block/md0/md/dev-hdb1/block -> ../../../../block/hdb/hdb1 super @@ -358,51 +423,83 @@ Each directory contains: state A file recording the current state of the device in the array - which can be a comma separated list of - faulty - device has been kicked from active use due to - a detected fault, or it has unacknowledged bad - blocks - in_sync - device is a fully in-sync member of the array - writemostly - device will only be subject to read - requests if there are no other options. - This applies only to raid1 arrays. - blocked - device has failed, and the failure hasn't been - acknowledged yet by the metadata handler. - Writes that would write to this device if - it were not faulty are blocked. - spare - device is working, but not a full member. - This includes spares that are in the process - of being recovered to - write_error - device has ever seen a write error. - want_replacement - device is (mostly) working but probably - should be replaced, either due to errors or - due to user request. - replacement - device is a replacement for another active - device with same raid_disk. + which can be a comma separated list of: + + faulty + device has been kicked from active use due to + a detected fault, or it has unacknowledged bad + blocks + + in_sync + device is a fully in-sync member of the array + + writemostly + device will only be subject to read + requests if there are no other options. + + This applies only to raid1 arrays. + + blocked + device has failed, and the failure hasn't been + acknowledged yet by the metadata handler. + + Writes that would write to this device if + it were not faulty are blocked. + + spare + device is working, but not a full member. + + This includes spares that are in the process + of being recovered to + + write_error + device has ever seen a write error. + + want_replacement + device is (mostly) working but probably + should be replaced, either due to errors or + due to user request. + + replacement + device is a replacement for another active + device with same raid_disk. This list may grow in future. + This can be written to. - Writing "faulty" simulates a failure on the device. - Writing "remove" removes the device from the array. - Writing "writemostly" sets the writemostly flag. - Writing "-writemostly" clears the writemostly flag. - Writing "blocked" sets the "blocked" flag. - Writing "-blocked" clears the "blocked" flags and allows writes - to complete and possibly simulates an error. - Writing "in_sync" sets the in_sync flag. - Writing "write_error" sets writeerrorseen flag. - Writing "-write_error" clears writeerrorseen flag. - Writing "want_replacement" is allowed at any time except to a - replacement device or a spare. It sets the flag. - Writing "-want_replacement" is allowed at any time. It clears - the flag. - Writing "replacement" or "-replacement" is only allowed before - starting the array. It sets or clears the flag. - - - This file responds to select/poll. Any change to 'faulty' - or 'blocked' causes an event. + + Writing ``faulty`` simulates a failure on the device. + + Writing ``remove`` removes the device from the array. + + Writing ``writemostly`` sets the writemostly flag. + + Writing ``-writemostly`` clears the writemostly flag. + + Writing ``blocked`` sets the ``blocked`` flag. + + Writing ``-blocked`` clears the ``blocked`` flags and allows writes + to complete and possibly simulates an error. + + Writing ``in_sync`` sets the in_sync flag. + + Writing ``write_error`` sets writeerrorseen flag. + + Writing ``-write_error`` clears writeerrorseen flag. + + Writing ``want_replacement`` is allowed at any time except to a + replacement device or a spare. It sets the flag. + + Writing ``-want_replacement`` is allowed at any time. It clears + the flag. + + Writing ``replacement`` or ``-replacement`` is only allowed before + starting the array. It sets or clears the flag. + + + This file responds to select/poll. Any change to ``faulty`` + or ``blocked`` causes an event. errors An approximate count of read errors that have been detected on @@ -417,9 +514,9 @@ Each directory contains: slot This gives the role that the device has in the array. It will - either be 'none' if the device is not active in the array + either be ``none`` if the device is not active in the array (i.e. is a spare or has failed) or an integer less than the - 'raid_disks' number for the array indicating which position + ``raid_disks`` number for the array indicating which position it currently fills. This can only be set while assembling an array. A device for which this is set is assumed to be working. @@ -437,7 +534,7 @@ Each directory contains: written, it will be rejected. recovery_start - When the device is not 'in_sync', this records the number of + When the device is not ``in_sync``, this records the number of sectors from the start of the device which are known to be correct. This is normally zero, but during a recovery operation it will steadily increase, and if the recovery is @@ -447,21 +544,21 @@ Each directory contains: This can be set whenever the device is not an active member of the array, either before the array is activated, or before - the 'slot' is set. + the ``slot`` is set. + + Setting this to ``none`` is equivalent to setting ``in_sync``. + Setting to any other value also clears the ``in_sync`` flag. - Setting this to 'none' is equivalent to setting 'in_sync'. - Setting to any other value also clears the 'in_sync' flag. - bad_blocks This gives the list of all known bad blocks in the form of start address and length (in sectors respectively). If output is too big to fit in a page, it will be truncated. Writing - "sector length" to this file adds new acknowledged (i.e. + ``sector length`` to this file adds new acknowledged (i.e. recorded to disk safely) bad blocks. unacknowledged_bad_blocks This gives the list of known-but-not-yet-saved-to-disk bad - blocks in the same form of 'bad_blocks'. If output is too big + blocks in the same form of ``bad_blocks``. If output is too big to fit in a page, it will be truncated. Writing to this file adds bad blocks without acknowledging them. This is largely for testing. @@ -469,16 +566,18 @@ Each directory contains: An active md device will also contain an entry for each active device -in the array. These are named +in the array. These are named:: rdNN -where 'NN' is the position in the array, starting from 0. +where ``NN`` is the position in the array, starting from 0. So for a 3 drive array there will be rd0, rd1, rd2. -These are symbolic links to the appropriate 'dev-XXX' entry. -Thus, for example, +These are symbolic links to the appropriate ``dev-XXX`` entry. +Thus, for example:: + cat /sys/block/md*/md/rd*/state -will show 'in_sync' on every line. + +will show ``in_sync`` on every line. @@ -488,50 +587,62 @@ also have sync_action a text file that can be used to monitor and control the rebuild process. It contains one word which can be one of: - resync - redundancy is being recalculated after unclean - shutdown or creation - recover - a hot spare is being built to replace a - failed/missing device - idle - nothing is happening - check - A full check of redundancy was requested and is - happening. This reads all blocks and checks - them. A repair may also happen for some raid - levels. - repair - A full check and repair is happening. This is - similar to 'resync', but was requested by the - user, and the write-intent bitmap is NOT used to - optimise the process. + + resync + redundancy is being recalculated after unclean + shutdown or creation + + recover + a hot spare is being built to replace a + failed/missing device + + idle + nothing is happening + check + A full check of redundancy was requested and is + happening. This reads all blocks and checks + them. A repair may also happen for some raid + levels. + + repair + A full check and repair is happening. This is + similar to ``resync``, but was requested by the + user, and the write-intent bitmap is NOT used to + optimise the process. This file is writable, and each of the strings that could be read are meaningful for writing. - 'idle' will stop an active resync/recovery etc. There is no - guarantee that another resync/recovery may not be automatically - started again, though some event will be needed to trigger - this. - 'resync' or 'recovery' can be used to restart the - corresponding operation if it was stopped with 'idle'. - 'check' and 'repair' will start the appropriate process - providing the current state is 'idle'. + ``idle`` will stop an active resync/recovery etc. There is no + guarantee that another resync/recovery may not be automatically + started again, though some event will be needed to trigger + this. + + ``resync`` or ``recovery`` can be used to restart the + corresponding operation if it was stopped with ``idle``. + + ``check`` and ``repair`` will start the appropriate process + providing the current state is ``idle``. This file responds to select/poll. Any important change in the value triggers a poll event. Sometimes the value will briefly be - "recover" if a recovery seems to be needed, but cannot be - achieved. In that case, the transition to "recover" isn't + ``recover`` if a recovery seems to be needed, but cannot be + achieved. In that case, the transition to ``recover`` isn't notified, but the transition away is. degraded This contains a count of the number of devices by which the - arrays is degraded. So an optimal array will show '0'. A - single failed/missing drive will show '1', etc. + arrays is degraded. So an optimal array will show ``0``. A + single failed/missing drive will show ``1``, etc. + This file responds to select/poll, any increase or decrease in the count of missing devices will trigger an event. mismatch_count - When performing 'check' and 'repair', and possibly when - performing 'resync', md will count the number of errors that are - found. The count in 'mismatch_cnt' is the number of sectors - that were re-written, or (for 'check') would have been + When performing ``check`` and ``repair``, and possibly when + performing ``resync``, md will count the number of errors that are + found. The count in ``mismatch_cnt`` is the number of sectors + that were re-written, or (for ``check``) would have been re-written. As most raid levels work in units of pages rather than sectors, this may be larger than the number of actual errors by a factor of the number of sectors in a page. @@ -542,27 +653,30 @@ also have would need to check the corresponding blocks. Either individual numbers or start-end pairs can be written. Multiple numbers can be separated by a space. - Note that the numbers are 'bit' numbers, not 'block' numbers. + + Note that the numbers are ``bit`` numbers, not ``block`` numbers. They should be scaled by the bitmap_chunksize. - sync_speed_min - sync_speed_max - This are similar to /proc/sys/dev/raid/speed_limit_{min,max} + sync_speed_min, sync_speed_max + This are similar to ``/proc/sys/dev/raid/speed_limit_{min,max}`` however they only apply to the particular array. - If no value has been written to these, or if the word 'system' + + If no value has been written to these, or if the word ``system`` is written, then the system-wide value is used. If a value, in kibibytes-per-second is written, then it is used. + When the files are read, they show the currently active value - followed by "(local)" or "(system)" depending on whether it is + followed by ``(local)`` or ``(system)`` depending on whether it is a locally set or system-wide value. sync_completed This shows the number of sectors that have been completed of whatever the current sync_action is, followed by the number of sectors in total that could need to be processed. The two - numbers are separated by a '/' thus effectively showing one + numbers are separated by a ``/`` thus effectively showing one value, a fraction of the process that is complete. - A 'select' on this attribute will return when resync completes, + + A ``select`` on this attribute will return when resync completes, when it reaches the current sync_max (below) and possibly at other times. @@ -570,26 +684,24 @@ also have This shows the current actual speed, in K/sec, of the current sync_action. It is averaged over the last 30 seconds. - suspend_lo - suspend_hi + suspend_lo, suspend_hi The two values, given as numbers of sectors, indicate a range within the array where IO will be blocked. This is currently only supported for raid4/5/6. - sync_min - sync_max + sync_min, sync_max The two values, given as numbers of sectors, indicate a range - within the array where 'check'/'repair' will operate. Must be - a multiple of chunk_size. When it reaches "sync_max" it will + within the array where ``check``/``repair`` will operate. Must be + a multiple of chunk_size. When it reaches ``sync_max`` it will pause, rather than complete. - You can use 'select' or 'poll' on "sync_completed" to wait for + You can use ``select`` or ``poll`` on ``sync_completed`` to wait for that number to reach sync_max. Then you can either increase - "sync_max", or can write 'idle' to "sync_action". + ``sync_max``, or can write ``idle`` to ``sync_action``. - The value of 'max' for "sync_max" effectively disables the limit. + The value of ``max`` for ``sync_max`` effectively disables the limit. When a resync is active, the value can only ever be increased, never decreased. - The value of '0' is the minimum for "sync_min". + The value of ``0`` is the minimum for ``sync_min``. @@ -598,13 +710,15 @@ personality module that manages it. These are specific to the implementation of the module and could change substantially if the implementation changes. -These currently include +These currently include: stripe_cache_size (currently raid5 only) number of entries in the stripe cache. This is writable, but there are upper and lower limits (32768, 17). Default is 256. + strip_cache_active (currently raid5 only) number of active entries in the stripe cache + preread_bypass_threshold (currently raid5 only) number of times a stripe requiring preread will be bypassed by a stripe that does not require preread. For fairness defaults diff --git a/Documentation/module-signing.txt b/Documentation/admin-guide/module-signing.rst index f0e3361..27e5949 100644 --- a/Documentation/module-signing.txt +++ b/Documentation/admin-guide/module-signing.rst @@ -1,22 +1,21 @@ - ============================== - KERNEL MODULE SIGNING FACILITY - ============================== - -CONTENTS - - - Overview. - - Configuring module signing. - - Generating signing keys. - - Public keys in the kernel. - - Manually signing modules. - - Signed modules and stripping. - - Loading signed modules. - - Non-valid signatures and unsigned modules. - - Administering/protecting the private key. +Kernel module signing facility +------------------------------ + +.. CONTENTS +.. +.. - Overview. +.. - Configuring module signing. +.. - Generating signing keys. +.. - Public keys in the kernel. +.. - Manually signing modules. +.. - Signed modules and stripping. +.. - Loading signed modules. +.. - Non-valid signatures and unsigned modules. +.. - Administering/protecting the private key. ======== -OVERVIEW +Overview ======== The kernel module signing facility cryptographically signs modules during @@ -36,17 +35,19 @@ SHA-512 (the algorithm is selected by data in the signature). ========================== -CONFIGURING MODULE SIGNING +Configuring module signing ========================== -The module signing facility is enabled by going to the "Enable Loadable Module -Support" section of the kernel configuration and turning on +The module signing facility is enabled by going to the +:menuselection:`Enable Loadable Module Support` section of +the kernel configuration and turning on:: CONFIG_MODULE_SIG "Module signature verification" This has a number of options available: - (1) "Require modules to be validly signed" (CONFIG_MODULE_SIG_FORCE) + (1) :menuselection:`Require modules to be validly signed` + (``CONFIG_MODULE_SIG_FORCE``) This specifies how the kernel should deal with a module that has a signature for which the key is not known or a module that is unsigned. @@ -64,35 +65,39 @@ This has a number of options available: cannot be parsed, it will be rejected out of hand. - (2) "Automatically sign all modules" (CONFIG_MODULE_SIG_ALL) + (2) :menuselection:`Automatically sign all modules` + (``CONFIG_MODULE_SIG_ALL``) If this is on then modules will be automatically signed during the modules_install phase of a build. If this is off, then the modules must - be signed manually using: + be signed manually using:: scripts/sign-file - (3) "Which hash algorithm should modules be signed with?" + (3) :menuselection:`Which hash algorithm should modules be signed with?` This presents a choice of which hash algorithm the installation phase will sign the modules with: - CONFIG_MODULE_SIG_SHA1 "Sign modules with SHA-1" - CONFIG_MODULE_SIG_SHA224 "Sign modules with SHA-224" - CONFIG_MODULE_SIG_SHA256 "Sign modules with SHA-256" - CONFIG_MODULE_SIG_SHA384 "Sign modules with SHA-384" - CONFIG_MODULE_SIG_SHA512 "Sign modules with SHA-512" + =============================== ========================================== + ``CONFIG_MODULE_SIG_SHA1`` :menuselection:`Sign modules with SHA-1` + ``CONFIG_MODULE_SIG_SHA224`` :menuselection:`Sign modules with SHA-224` + ``CONFIG_MODULE_SIG_SHA256`` :menuselection:`Sign modules with SHA-256` + ``CONFIG_MODULE_SIG_SHA384`` :menuselection:`Sign modules with SHA-384` + ``CONFIG_MODULE_SIG_SHA512`` :menuselection:`Sign modules with SHA-512` + =============================== ========================================== The algorithm selected here will also be built into the kernel (rather than being a module) so that modules signed with that algorithm can have their signatures checked without causing a dependency loop. - (4) "File name or PKCS#11 URI of module signing key" (CONFIG_MODULE_SIG_KEY) + (4) :menuselection:`File name or PKCS#11 URI of module signing key` + (``CONFIG_MODULE_SIG_KEY``) Setting this option to something other than its default of - "certs/signing_key.pem" will disable the autogeneration of signing keys + ``certs/signing_key.pem`` will disable the autogeneration of signing keys and allow the kernel modules to be signed with a key of your choosing. The string provided should identify a file containing both a private key and its corresponding X.509 certificate in PEM form, or — on systems where @@ -102,10 +107,11 @@ This has a number of options available: If the PEM file containing the private key is encrypted, or if the PKCS#11 token requries a PIN, this can be provided at build time by - means of the KBUILD_SIGN_PIN variable. + means of the ``KBUILD_SIGN_PIN`` variable. - (5) "Additional X.509 keys for default system keyring" (CONFIG_SYSTEM_TRUSTED_KEYS) + (5) :menuselection:`Additional X.509 keys for default system keyring` + (``CONFIG_SYSTEM_TRUSTED_KEYS``) This option can be set to the filename of a PEM-encoded file containing additional certificates which will be included in the system keyring by @@ -116,7 +122,7 @@ packages to the kernel build processes for the tool that does the signing. ======================= -GENERATING SIGNING KEYS +Generating signing keys ======================= Cryptographic keypairs are required to generate and check signatures. A @@ -126,14 +132,14 @@ it can be deleted or stored securely. The public key gets built into the kernel so that it can be used to check the signatures as the modules are loaded. -Under normal conditions, when CONFIG_MODULE_SIG_KEY is unchanged from its +Under normal conditions, when ``CONFIG_MODULE_SIG_KEY`` is unchanged from its default, the kernel build will automatically generate a new keypair using -openssl if one does not exist in the file: +openssl if one does not exist in the file:: certs/signing_key.pem during the building of vmlinux (the public part of the key needs to be built -into vmlinux) using parameters in the: +into vmlinux) using parameters in the:: certs/x509.genkey @@ -142,14 +148,14 @@ file (which is also generated if it does not already exist). It is strongly recommended that you provide your own x509.genkey file. Most notably, in the x509.genkey file, the req_distinguished_name section -should be altered from the default: +should be altered from the default:: [ req_distinguished_name ] #O = Unspecified company CN = Build time autogenerated kernel key #emailAddress = unspecified.user@unspecified.company -The generated RSA key size can also be set with: +The generated RSA key size can also be set with:: [ req ] default_bits = 4096 @@ -158,23 +164,23 @@ The generated RSA key size can also be set with: It is also possible to manually generate the key private/public files using the x509.genkey key generation configuration file in the root node of the Linux kernel sources tree and the openssl command. The following is an example to -generate the public/private key files: +generate the public/private key files:: openssl req -new -nodes -utf8 -sha256 -days 36500 -batch -x509 \ -config x509.genkey -outform PEM -out kernel_key.pem \ -keyout kernel_key.pem The full pathname for the resulting kernel_key.pem file can then be specified -in the CONFIG_MODULE_SIG_KEY option, and the certificate and key therein will +in the ``CONFIG_MODULE_SIG_KEY`` option, and the certificate and key therein will be used instead of an autogenerated keypair. ========================= -PUBLIC KEYS IN THE KERNEL +Public keys in the kernel ========================= The kernel contains a ring of public keys that can be viewed by root. They're -in a keyring called ".system_keyring" that can be seen by: +in a keyring called ".system_keyring" that can be seen by:: [root@deneb ~]# cat /proc/keys ... @@ -184,27 +190,27 @@ in a keyring called ".system_keyring" that can be seen by: Beyond the public key generated specifically for module signing, additional trusted certificates can be provided in a PEM-encoded file referenced by the -CONFIG_SYSTEM_TRUSTED_KEYS configuration option. +``CONFIG_SYSTEM_TRUSTED_KEYS`` configuration option. Further, the architecture code may take public keys from a hardware store and add those in also (e.g. from the UEFI key database). -Finally, it is possible to add additional public keys by doing: +Finally, it is possible to add additional public keys by doing:: keyctl padd asymmetric "" [.system_keyring-ID] <[key-file] -e.g.: +e.g.:: keyctl padd asymmetric "" 0x223c7853 <my_public_key.x509 Note, however, that the kernel will only permit keys to be added to -.system_keyring _if_ the new key's X.509 wrapper is validly signed by a key +``.system_keyring _if_`` the new key's X.509 wrapper is validly signed by a key that is already resident in the .system_keyring at the time the key was added. -========================= -MANUALLY SIGNING MODULES -========================= +======================== +Manually signing modules +======================== To manually sign a module, use the scripts/sign-file tool available in the Linux kernel source tree. The script requires 4 arguments: @@ -214,7 +220,7 @@ the Linux kernel source tree. The script requires 4 arguments: 3. The public key filename 4. The kernel module to be signed -The following is an example to sign a kernel module: +The following is an example to sign a kernel module:: scripts/sign-file sha512 kernel-signkey.priv \ kernel-signkey.x509 module.ko @@ -228,11 +234,11 @@ $KBUILD_SIGN_PIN environment variable. ============================ -SIGNED MODULES AND STRIPPING +Signed modules and stripping ============================ A signed module has a digital signature simply appended at the end. The string -"~Module signature appended~." at the end of the module's file confirms that a +``~Module signature appended~.`` at the end of the module's file confirms that a signature is present but it does not confirm that the signature is valid! Signed modules are BRITTLE as the signature is outside of the defined ELF @@ -242,19 +248,19 @@ debug information present at the time of signing. ====================== -LOADING SIGNED MODULES +Loading signed modules ====================== -Modules are loaded with insmod, modprobe, init_module() or finit_module(), -exactly as for unsigned modules as no processing is done in userspace. The -signature checking is all done within the kernel. +Modules are loaded with insmod, modprobe, ``init_module()`` or +``finit_module()``, exactly as for unsigned modules as no processing is +done in userspace. The signature checking is all done within the kernel. ========================================= -NON-VALID SIGNATURES AND UNSIGNED MODULES +Non-valid signatures and unsigned modules ========================================= -If CONFIG_MODULE_SIG_FORCE is enabled or module.sig_enforce=1 is supplied on +If ``CONFIG_MODULE_SIG_FORCE`` is enabled or module.sig_enforce=1 is supplied on the kernel command line, the kernel will only load validly signed modules for which it has a public key. Otherwise, it will also load modules that are unsigned. Any module for which the kernel has a key, but which proves to have @@ -264,7 +270,7 @@ Any module that has an unparseable signature will be rejected. ========================================= -ADMINISTERING/PROTECTING THE PRIVATE KEY +Administering/protecting the private key ========================================= Since the private key is used to sign modules, viruses and malware could use @@ -275,5 +281,5 @@ in the root node of the kernel source tree. If you use the same private key to sign modules for multiple kernel configurations, you must ensure that the module version information is sufficient to prevent loading a module into a different kernel. Either -set CONFIG_MODVERSIONS=y or ensure that each configuration has a different -kernel release string by changing EXTRAVERSION or CONFIG_LOCALVERSION. +set ``CONFIG_MODVERSIONS=y`` or ensure that each configuration has a different +kernel release string by changing ``EXTRAVERSION`` or ``CONFIG_LOCALVERSION``. diff --git a/Documentation/mono.txt b/Documentation/admin-guide/mono.rst index d01ac60..9a9744c 100644 --- a/Documentation/mono.txt +++ b/Documentation/admin-guide/mono.rst @@ -1,5 +1,5 @@ - Mono(tm) Binary Kernel Support for Linux - ----------------------------------------- +Mono(tm) Binary Kernel Support for Linux +----------------------------------------- To configure Linux to automatically execute Mono-based .NET binaries (in the form of .exe files) without the need to use the mono CLR @@ -19,22 +19,22 @@ other program after you have done the following: http://www.go-mono.com/compiling.html Once the Mono CLR support has been installed, just check that - /usr/bin/mono (which could be located elsewhere, for example - /usr/local/bin/mono) is working. + ``/usr/bin/mono`` (which could be located elsewhere, for example + ``/usr/local/bin/mono``) is working. 2) You have to compile BINFMT_MISC either as a module or into - the kernel (CONFIG_BINFMT_MISC) and set it up properly. + the kernel (``CONFIG_BINFMT_MISC``) and set it up properly. If you choose to compile it as a module, you will have to insert it manually with modprobe/insmod, as kmod - cannot be easily supported with binfmt_misc. - Read the file 'binfmt_misc.txt' in this directory to know + cannot be easily supported with binfmt_misc. + Read the file ``binfmt_misc.txt`` in this directory to know more about the configuration process. -3) Add the following entries to /etc/rc.local or similar script - to be run at system startup: +3) Add the following entries to ``/etc/rc.local`` or similar script + to be run at system startup:: -# Insert BINFMT_MISC module into the kernel -if [ ! -e /proc/sys/fs/binfmt_misc/register ]; then + # Insert BINFMT_MISC module into the kernel + if [ ! -e /proc/sys/fs/binfmt_misc/register ]; then /sbin/modprobe binfmt_misc # Some distributions, like Fedora Core, perform # the following command automatically when the @@ -43,24 +43,26 @@ if [ ! -e /proc/sys/fs/binfmt_misc/register ]; then # Thus, it is possible that the following line # is not needed at all. mount -t binfmt_misc none /proc/sys/fs/binfmt_misc -fi + fi -# Register support for .NET CLR binaries -if [ -e /proc/sys/fs/binfmt_misc/register ]; then + # Register support for .NET CLR binaries + if [ -e /proc/sys/fs/binfmt_misc/register ]; then # Replace /usr/bin/mono with the correct pathname to # the Mono CLR runtime (usually /usr/local/bin/mono # when compiling from sources or CVS). echo ':CLR:M::MZ::/usr/bin/mono:' > /proc/sys/fs/binfmt_misc/register -else + else echo "No binfmt_misc support" exit 1 -fi + fi -4) Check that .exe binaries can be ran without the need of a - wrapper script, simply by launching the .exe file directly - from a command prompt, for example: +4) Check that ``.exe`` binaries can be ran without the need of a + wrapper script, simply by launching the ``.exe`` file directly + from a command prompt, for example:: /usr/bin/xsd.exe - NOTE: If this fails with a permission denied error, check - that the .exe file has execute permissions. + .. note:: + + If this fails with a permission denied error, check + that the ``.exe`` file has execute permissions. diff --git a/Documentation/oops-tracing.txt b/Documentation/admin-guide/oops-tracing.rst index f3ac05c..13be8d7 100644 --- a/Documentation/oops-tracing.txt +++ b/Documentation/admin-guide/oops-tracing.rst @@ -1,7 +1,13 @@ -NOTE: ksymoops is useless on 2.6. Please use the Oops in its original format -(from dmesg, etc). Ignore any references in this or other docs to "decoding -the Oops" or "running it through ksymoops". If you post an Oops from 2.6 that -has been run through ksymoops, people will just tell you to repost it. +OOPS tracing +============ + +.. note:: + + ``ksymoops`` is useless on 2.6 or upper. Please use the Oops in its original + format (from ``dmesg``, etc). Ignore any references in this or other docs to + "decoding the Oops" or "running it through ksymoops". + If you post an Oops from 2.6+ that has been run through ``ksymoops``, + people will just tell you to repost it. Quick Summary ------------- @@ -12,7 +18,7 @@ If you are unsure send it to the person responsible for the code relevant to what you were doing. If it occurs repeatably try and describe how to recreate it. That's worth even more than the oops. -If you are totally stumped as to whom to send the report, send it to +If you are totally stumped as to whom to send the report, send it to linux-kernel@vger.kernel.org. Thanks for your help in making Linux as stable as humanly possible. @@ -20,24 +26,25 @@ Where is the Oops? ---------------------- Normally the Oops text is read from the kernel buffers by klogd and -handed to syslogd which writes it to a syslog file, typically -/var/log/messages (depends on /etc/syslog.conf). Sometimes klogd dies, -in which case you can run dmesg > file to read the data from the kernel -buffers and save it. Or you can cat /proc/kmsg > file, however you -have to break in to stop the transfer, kmsg is a "never ending file". +handed to ``syslogd`` which writes it to a syslog file, typically +``/var/log/messages`` (depends on ``/etc/syslog.conf``). Sometimes ``klogd`` +dies, in which case you can run ``dmesg > file`` to read the data from the +kernel buffers and save it. Or you can ``cat /proc/kmsg > file``, however you +have to break in to stop the transfer, ``kmsg`` is a "never ending file". If the machine has crashed so badly that you cannot enter commands or -the disk is not available then you have three options :- +the disk is not available then you have three options : (1) Hand copy the text from the screen and type it in after the machine has restarted. Messy but it is the only option if you have not planned for a crash. Alternatively, you can take a picture of the screen with a digital camera - not nice, but better than nothing. If the messages scroll off the top of the console, you - may find that booting with a higher resolution (eg, vga=791) - will allow you to read more of the text. (Caveat: This needs vesafb, + may find that booting with a higher resolution (eg, ``vga=791``) + will allow you to read more of the text. (Caveat: This needs ``vesafb``, so won't help for 'early' oopses) -(2) Boot with a serial console (see Documentation/serial-console.txt), +(2) Boot with a serial console (see + :ref:`Documentation/admin-guide/serial-console.rst <serial_console>`), run a null modem to a second machine and capture the output there using your favourite communication program. Minicom works well. @@ -49,117 +56,126 @@ the disk is not available then you have three options :- Full Information ---------------- -NOTE: the message from Linus below applies to 2.4 kernel. I have preserved it -for historical reasons, and because some of the information in it still -applies. Especially, please ignore any references to ksymoops. +.. note:: + + the message from Linus below applies to 2.4 kernel. I have preserved it + for historical reasons, and because some of the information in it still + applies. Especially, please ignore any references to ksymoops. -From: Linus Torvalds <torvalds@osdl.org> + :: -How to track down an Oops.. [originally a mail to linux-kernel] + From: Linus Torvalds <torvalds@osdl.org> -The main trick is having 5 years of experience with those pesky oops -messages ;-) + How to track down an Oops.. [originally a mail to linux-kernel] -Actually, there are things you can do that make this easier. I have two -separate approaches: + The main trick is having 5 years of experience with those pesky oops + messages ;-) + +Actually, there are things you can do that make this easier. I have two +separate approaches:: gdb /usr/src/linux/vmlinux gdb> disassemble <offending_function> -That's the easy way to find the problem, at least if the bug-report is -well made (like this one was - run through ksymoops to get the -information of which function and the offset in the function that it +That's the easy way to find the problem, at least if the bug-report is +well made (like this one was - run through ``ksymoops`` to get the +information of which function and the offset in the function that it happened in). -Oh, it helps if the report happens on a kernel that is compiled with the +Oh, it helps if the report happens on a kernel that is compiled with the same compiler and similar setups. -The other thing to do is disassemble the "Code:" part of the bug report: +The other thing to do is disassemble the "Code:" part of the bug report: ksymoops will do this too with the correct tools, but if you don't have -the tools you can just do a silly program: +the tools you can just do a silly program:: char str[] = "\xXX\xXX\xXX..."; main(){} -and compile it with gcc -g and then do "disassemble str" (where the "XX" -stuff are the values reported by the Oops - you can just cut-and-paste -and do a replace of spaces to "\x" - that's what I do, as I'm too lazy +and compile it with ``gcc -g`` and then do ``disassemble str`` (where the ``XX`` +stuff are the values reported by the Oops - you can just cut-and-paste +and do a replace of spaces to ``\x`` - that's what I do, as I'm too lazy to write a program to automate this all). -Alternatively, you can use the shell script in scripts/decodecode. -Its usage is: decodecode < oops.txt +Alternatively, you can use the shell script in ``scripts/decodecode``. +Its usage is:: + + decodecode < oops.txt The hex bytes that follow "Code:" may (in some architectures) have a series of bytes that precede the current instruction pointer as well as bytes at and following the current instruction pointer. In some cases, one instruction -byte or word is surrounded by <> or (), as in "<86>" or "(f00d)". These -<> or () markings indicate the current instruction pointer. Example from -i386, split into multiple lines for readability: +byte or word is surrounded by ``<>`` or ``()``, as in ``<86>`` or ``(f00d)``. +These ``<>`` or ``()`` markings indicate the current instruction pointer. + +Example from i386, split into multiple lines for readability:: -Code: f9 0f 8d f9 00 00 00 8d 42 0c e8 dd 26 11 c7 a1 60 ea 2b f9 8b 50 08 a1 -64 ea 2b f9 8d 34 82 8b 1e 85 db 74 6d 8b 15 60 ea 2b f9 <8b> 43 04 39 42 54 -7e 04 40 89 42 54 8b 43 04 3b 05 00 f6 52 c0 + Code: f9 0f 8d f9 00 00 00 8d 42 0c e8 dd 26 11 c7 a1 60 ea 2b f9 8b 50 08 a1 + 64 ea 2b f9 8d 34 82 8b 1e 85 db 74 6d 8b 15 60 ea 2b f9 <8b> 43 04 39 42 54 + 7e 04 40 89 42 54 8b 43 04 3b 05 00 f6 52 c0 -Finally, if you want to see where the code comes from, you can do +Finally, if you want to see where the code comes from, you can do:: cd /usr/src/linux make fs/buffer.s # or whatever file the bug happened in -and then you get a better idea of what happens than with the gdb +and then you get a better idea of what happens than with the gdb disassembly. -Now, the trick is just then to combine all the data you have: the C -sources (and general knowledge of what it _should_ do), the assembly -listing and the code disassembly (and additionally the register dump you -also get from the "oops" message - that can be useful to see _what_ the -corrupted pointers were, and when you have the assembler listing you can -also match the other registers to whatever C expressions they were used +Now, the trick is just then to combine all the data you have: the C +sources (and general knowledge of what it **should** do), the assembly +listing and the code disassembly (and additionally the register dump you +also get from the "oops" message - that can be useful to see **what** the +corrupted pointers were, and when you have the assembler listing you can +also match the other registers to whatever C expressions they were used for). -Essentially, you just look at what doesn't match (in this case it was the -"Code" disassembly that didn't match with what the compiler generated). -Then you need to find out _why_ they don't match. Often it's simple - you -see that the code uses a NULL pointer and then you look at the code and -wonder how the NULL pointer got there, and if it's a valid thing to do +Essentially, you just look at what doesn't match (in this case it was the +"Code" disassembly that didn't match with what the compiler generated). +Then you need to find out **why** they don't match. Often it's simple - you +see that the code uses a NULL pointer and then you look at the code and +wonder how the NULL pointer got there, and if it's a valid thing to do you just check against it.. -Now, if somebody gets the idea that this is time-consuming and requires -some small amount of concentration, you're right. Which is why I will -mostly just ignore any panic reports that don't have the symbol table -info etc looked up: it simply gets too hard to look it up (I have some -programs to search for specific patterns in the kernel code segment, and -sometimes I have been able to look up those kinds of panics too, but -that really requires pretty good knowledge of the kernel just to be able +Now, if somebody gets the idea that this is time-consuming and requires +some small amount of concentration, you're right. Which is why I will +mostly just ignore any panic reports that don't have the symbol table +info etc looked up: it simply gets too hard to look it up (I have some +programs to search for specific patterns in the kernel code segment, and +sometimes I have been able to look up those kinds of panics too, but +that really requires pretty good knowledge of the kernel just to be able to pick out the right sequences etc..) -_Sometimes_ it happens that I just see the disassembled code sequence -from the panic, and I know immediately where it's coming from. That's when +**Sometimes** it happens that I just see the disassembled code sequence +from the panic, and I know immediately where it's coming from. That's when I get worried that I've been doing this for too long ;-) Linus --------------------------------------------------------------------------- -Notes on Oops tracing with klogd: + +Notes on Oops tracing with ``klogd`` +------------------------------------ In order to help Linus and the other kernel developers there has been -substantial support incorporated into klogd for processing protection +substantial support incorporated into ``klogd`` for processing protection faults. In order to have full support for address resolution at least -version 1.3-pl3 of the sysklogd package should be used. +version 1.3-pl3 of the ``sysklogd`` package should be used. -When a protection fault occurs the klogd daemon automatically +When a protection fault occurs the ``klogd`` daemon automatically translates important addresses in the kernel log messages to their symbolic equivalents. This translated kernel message is then -forwarded through whatever reporting mechanism klogd is using. The +forwarded through whatever reporting mechanism ``klogd`` is using. The protection fault message can be simply cut out of the message files and forwarded to the kernel developers. -Two types of address resolution are performed by klogd. The first is +Two types of address resolution are performed by ``klogd``. The first is static translation and the second is dynamic translation. Static translation uses the System.map file in much the same manner that -ksymoops does. In order to do static translation the klogd daemon +ksymoops does. In order to do static translation the ``klogd`` daemon must be able to find a system map file at daemon initialization time. -See the klogd man page for information on how klogd searches for map +See the klogd man page for information on how ``klogd`` searches for map files. Dynamic address translation is important when kernel loadable modules @@ -178,101 +194,106 @@ information available if the developer of the loadable module chose to export symbol information from the module. Since the kernel module environment can be dynamic there must be a -mechanism for notifying the klogd daemon when a change in module +mechanism for notifying the ``klogd`` daemon when a change in module environment occurs. There are command line options available which allow klogd to signal the currently executing daemon that symbol -information should be refreshed. See the klogd manual page for more +information should be refreshed. See the ``klogd`` manual page for more information. A patch is included with the sysklogd distribution which modifies the -modules-2.0.0 package to automatically signal klogd whenever a module +``modules-2.0.0`` package to automatically signal klogd whenever a module is loaded or unloaded. Applying this patch provides essentially seamless support for debugging protection faults which occur with kernel loadable modules. The following is an example of a protection fault in a loadable module -processed by klogd: ---------------------------------------------------------------------------- -Aug 29 09:51:01 blizard kernel: Unable to handle kernel paging request at virtual address f15e97cc -Aug 29 09:51:01 blizard kernel: current->tss.cr3 = 0062d000, %cr3 = 0062d000 -Aug 29 09:51:01 blizard kernel: *pde = 00000000 -Aug 29 09:51:01 blizard kernel: Oops: 0002 -Aug 29 09:51:01 blizard kernel: CPU: 0 -Aug 29 09:51:01 blizard kernel: EIP: 0010:[oops:_oops+16/3868] -Aug 29 09:51:01 blizard kernel: EFLAGS: 00010212 -Aug 29 09:51:01 blizard kernel: eax: 315e97cc ebx: 003a6f80 ecx: 001be77b edx: 00237c0c -Aug 29 09:51:01 blizard kernel: esi: 00000000 edi: bffffdb3 ebp: 00589f90 esp: 00589f8c -Aug 29 09:51:01 blizard kernel: ds: 0018 es: 0018 fs: 002b gs: 002b ss: 0018 -Aug 29 09:51:01 blizard kernel: Process oops_test (pid: 3374, process nr: 21, stackpage=00589000) -Aug 29 09:51:01 blizard kernel: Stack: 315e97cc 00589f98 0100b0b4 bffffed4 0012e38e 00240c64 003a6f80 00000001 -Aug 29 09:51:01 blizard kernel: 00000000 00237810 bfffff00 0010a7fa 00000003 00000001 00000000 bfffff00 -Aug 29 09:51:01 blizard kernel: bffffdb3 bffffed4 ffffffda 0000002b 0007002b 0000002b 0000002b 00000036 -Aug 29 09:51:01 blizard kernel: Call Trace: [oops:_oops_ioctl+48/80] [_sys_ioctl+254/272] [_system_call+82/128] -Aug 29 09:51:01 blizard kernel: Code: c7 00 05 00 00 00 eb 08 90 90 90 90 90 90 90 90 89 ec 5d c3 +processed by ``klogd``:: + + Aug 29 09:51:01 blizard kernel: Unable to handle kernel paging request at virtual address f15e97cc + Aug 29 09:51:01 blizard kernel: current->tss.cr3 = 0062d000, %cr3 = 0062d000 + Aug 29 09:51:01 blizard kernel: *pde = 00000000 + Aug 29 09:51:01 blizard kernel: Oops: 0002 + Aug 29 09:51:01 blizard kernel: CPU: 0 + Aug 29 09:51:01 blizard kernel: EIP: 0010:[oops:_oops+16/3868] + Aug 29 09:51:01 blizard kernel: EFLAGS: 00010212 + Aug 29 09:51:01 blizard kernel: eax: 315e97cc ebx: 003a6f80 ecx: 001be77b edx: 00237c0c + Aug 29 09:51:01 blizard kernel: esi: 00000000 edi: bffffdb3 ebp: 00589f90 esp: 00589f8c + Aug 29 09:51:01 blizard kernel: ds: 0018 es: 0018 fs: 002b gs: 002b ss: 0018 + Aug 29 09:51:01 blizard kernel: Process oops_test (pid: 3374, process nr: 21, stackpage=00589000) + Aug 29 09:51:01 blizard kernel: Stack: 315e97cc 00589f98 0100b0b4 bffffed4 0012e38e 00240c64 003a6f80 00000001 + Aug 29 09:51:01 blizard kernel: 00000000 00237810 bfffff00 0010a7fa 00000003 00000001 00000000 bfffff00 + Aug 29 09:51:01 blizard kernel: bffffdb3 bffffed4 ffffffda 0000002b 0007002b 0000002b 0000002b 00000036 + Aug 29 09:51:01 blizard kernel: Call Trace: [oops:_oops_ioctl+48/80] [_sys_ioctl+254/272] [_system_call+82/128] + Aug 29 09:51:01 blizard kernel: Code: c7 00 05 00 00 00 eb 08 90 90 90 90 90 90 90 90 89 ec 5d c3 + --------------------------------------------------------------------------- -Dr. G.W. Wettstein Oncology Research Div. Computing Facility -Roger Maris Cancer Center INTERNET: greg@wind.rmcc.com -820 4th St. N. -Fargo, ND 58122 -Phone: 701-234-7556 +:: + + Dr. G.W. Wettstein Oncology Research Div. Computing Facility + Roger Maris Cancer Center INTERNET: greg@wind.rmcc.com + 820 4th St. N. + Fargo, ND 58122 + Phone: 701-234-7556 --------------------------------------------------------------------------- -Tainted kernels: -Some oops reports contain the string 'Tainted: ' after the program +Tainted kernels +--------------- + +Some oops reports contain the string **'Tainted: '** after the program counter. This indicates that the kernel has been tainted by some mechanism. The string is followed by a series of position-sensitive characters, each representing a particular tainted value. - 1: 'G' if all modules loaded have a GPL or compatible license, 'P' if + 1) 'G' if all modules loaded have a GPL or compatible license, 'P' if any proprietary module has been loaded. Modules without a MODULE_LICENSE or with a MODULE_LICENSE that is not recognised by insmod as GPL compatible are assumed to be proprietary. - 2: 'F' if any module was force loaded by "insmod -f", ' ' if all + 2) ``F`` if any module was force loaded by ``insmod -f``, ``' '`` if all modules were loaded normally. - 3: 'S' if the oops occurred on an SMP kernel running on hardware that + 3) ``S`` if the oops occurred on an SMP kernel running on hardware that hasn't been certified as safe to run multiprocessor. Currently this occurs only on various Athlons that are not SMP capable. - 4: 'R' if a module was force unloaded by "rmmod -f", ' ' if all + 4) ``R`` if a module was force unloaded by ``rmmod -f``, ``' '`` if all modules were unloaded normally. - 5: 'M' if any processor has reported a Machine Check Exception, - ' ' if no Machine Check Exceptions have occurred. + 5) ``M`` if any processor has reported a Machine Check Exception, + ``' '`` if no Machine Check Exceptions have occurred. - 6: 'B' if a page-release function has found a bad page reference or + 6) ``B`` if a page-release function has found a bad page reference or some unexpected page flags. - 7: 'U' if a user or user application specifically requested that the - Tainted flag be set, ' ' otherwise. + 7) ``U`` if a user or user application specifically requested that the + Tainted flag be set, ``' '`` otherwise. - 8: 'D' if the kernel has died recently, i.e. there was an OOPS or BUG. + 8) ``D`` if the kernel has died recently, i.e. there was an OOPS or BUG. - 9: 'A' if the ACPI table has been overridden. + 9) ``A`` if the ACPI table has been overridden. - 10: 'W' if a warning has previously been issued by the kernel. + 10) ``W`` if a warning has previously been issued by the kernel. (Though some warnings may set more specific taint flags.) - 11: 'C' if a staging driver has been loaded. + 11) ``C`` if a staging driver has been loaded. - 12: 'I' if the kernel is working around a severe bug in the platform + 12) ``I`` if the kernel is working around a severe bug in the platform firmware (BIOS or similar). - 13: 'O' if an externally-built ("out-of-tree") module has been loaded. + 13) ``O`` if an externally-built ("out-of-tree") module has been loaded. - 14: 'E' if an unsigned module has been loaded in a kernel supporting + 14) ``E`` if an unsigned module has been loaded in a kernel supporting module signature. - 15: 'L' if a soft lockup has previously occurred on the system. + 15) ``L`` if a soft lockup has previously occurred on the system. - 16: 'K' if the kernel has been live patched. + 16) ``K`` if the kernel has been live patched. -The primary reason for the 'Tainted: ' string is to tell kernel +The primary reason for the **'Tainted: '** string is to tell kernel debuggers if this is a clean kernel or if anything unusual has occurred. Tainting is permanent: even if an offending module is unloaded, the tainted value remains to indicate that the kernel is not diff --git a/Documentation/admin-guide/parport.rst b/Documentation/admin-guide/parport.rst new file mode 100644 index 0000000..ad3f9b8 --- /dev/null +++ b/Documentation/admin-guide/parport.rst @@ -0,0 +1,286 @@ +Parport ++++++++ + +The ``parport`` code provides parallel-port support under Linux. This +includes the ability to share one port between multiple device +drivers. + +You can pass parameters to the ``parport`` code to override its automatic +detection of your hardware. This is particularly useful if you want +to use IRQs, since in general these can't be autoprobed successfully. +By default IRQs are not used even if they **can** be probed. This is +because there are a lot of people using the same IRQ for their +parallel port and a sound card or network card. + +The ``parport`` code is split into two parts: generic (which deals with +port-sharing) and architecture-dependent (which deals with actually +using the port). + + +Parport as modules +================== + +If you load the `parport`` code as a module, say:: + + # insmod parport + +to load the generic ``parport`` code. You then must load the +architecture-dependent code with (for example):: + + # insmod parport_pc io=0x3bc,0x378,0x278 irq=none,7,auto + +to tell the ``parport`` code that you want three PC-style ports, one at +0x3bc with no IRQ, one at 0x378 using IRQ 7, and one at 0x278 with an +auto-detected IRQ. Currently, PC-style (``parport_pc``), Sun ``bpp``, +Amiga, Atari, and MFC3 hardware is supported. + +PCI parallel I/O card support comes from ``parport_pc``. Base I/O +addresses should not be specified for supported PCI cards since they +are automatically detected. + + +modprobe +-------- + +If you use modprobe , you will find it useful to add lines as below to a +configuration file in /etc/modprobe.d/ directory:: + + alias parport_lowlevel parport_pc + options parport_pc io=0x378,0x278 irq=7,auto + +modprobe will load ``parport_pc`` (with the options ``io=0x378,0x278 irq=7,auto``) +whenever a parallel port device driver (such as ``lp``) is loaded. + +Note that these are example lines only! You shouldn't in general need +to specify any options to ``parport_pc`` in order to be able to use a +parallel port. + + +Parport probe [optional] +------------------------ + +In 2.2 kernels there was a module called ``parport_probe``, which was used +for collecting IEEE 1284 device ID information. This has now been +enhanced and now lives with the IEEE 1284 support. When a parallel +port is detected, the devices that are connected to it are analysed, +and information is logged like this:: + + parport0: Printer, BJC-210 (Canon) + +The probe information is available from files in ``/proc/sys/dev/parport/``. + + +Parport linked into the kernel statically +========================================= + +If you compile the ``parport`` code into the kernel, then you can use +kernel boot parameters to get the same effect. Add something like the +following to your LILO command line:: + + parport=0x3bc parport=0x378,7 parport=0x278,auto,nofifo + +You can have many ``parport=...`` statements, one for each port you want +to add. Adding ``parport=0`` to the kernel command-line will disable +parport support entirely. Adding ``parport=auto`` to the kernel +command-line will make ``parport`` use any IRQ lines or DMA channels that +it auto-detects. + + +Files in /proc +============== + +If you have configured the ``/proc`` filesystem into your kernel, you will +see a new directory entry: ``/proc/sys/dev/parport``. In there will be a +directory entry for each parallel port for which parport is +configured. In each of those directories are a collection of files +describing that parallel port. + +The ``/proc/sys/dev/parport`` directory tree looks like:: + + parport + |-- default + | |-- spintime + | `-- timeslice + |-- parport0 + | |-- autoprobe + | |-- autoprobe0 + | |-- autoprobe1 + | |-- autoprobe2 + | |-- autoprobe3 + | |-- devices + | | |-- active + | | `-- lp + | | `-- timeslice + | |-- base-addr + | |-- irq + | |-- dma + | |-- modes + | `-- spintime + `-- parport1 + |-- autoprobe + |-- autoprobe0 + |-- autoprobe1 + |-- autoprobe2 + |-- autoprobe3 + |-- devices + | |-- active + | `-- ppa + | `-- timeslice + |-- base-addr + |-- irq + |-- dma + |-- modes + `-- spintime + +.. tabularcolumns:: |p{4.0cm}|p{13.5cm}| + +======================= ======================================================= +File Contents +======================= ======================================================= +``devices/active`` A list of the device drivers using that port. A "+" + will appear by the name of the device currently using + the port (it might not appear against any). The + string "none" means that there are no device drivers + using that port. + +``base-addr`` Parallel port's base address, or addresses if the port + has more than one in which case they are separated + with tabs. These values might not have any sensible + meaning for some ports. + +``irq`` Parallel port's IRQ, or -1 if none is being used. + +``dma`` Parallel port's DMA channel, or -1 if none is being + used. + +``modes`` Parallel port's hardware modes, comma-separated, + meaning: + + - PCSPP + PC-style SPP registers are available. + + - TRISTATE + Port is bidirectional. + + - COMPAT + Hardware acceleration for printers is + available and will be used. + + - EPP + Hardware acceleration for EPP protocol + is available and will be used. + + - ECP + Hardware acceleration for ECP protocol + is available and will be used. + + - DMA + DMA is available and will be used. + + Note that the current implementation will only take + advantage of COMPAT and ECP modes if it has an IRQ + line to use. + +``autoprobe`` Any IEEE-1284 device ID information that has been + acquired from the (non-IEEE 1284.3) device. + +``autoprobe[0-3]`` IEEE 1284 device ID information retrieved from + daisy-chain devices that conform to IEEE 1284.3. + +``spintime`` The number of microseconds to busy-loop while waiting + for the peripheral to respond. You might find that + adjusting this improves performance, depending on your + peripherals. This is a port-wide setting, i.e. it + applies to all devices on a particular port. + +``timeslice`` The number of milliseconds that a device driver is + allowed to keep a port claimed for. This is advisory, + and driver can ignore it if it must. + +``default/*`` The defaults for spintime and timeslice. When a new + port is registered, it picks up the default spintime. + When a new device is registered, it picks up the + default timeslice. +======================= ======================================================= + +Device drivers +============== + +Once the parport code is initialised, you can attach device drivers to +specific ports. Normally this happens automatically; if the lp driver +is loaded it will create one lp device for each port found. You can +override this, though, by using parameters either when you load the lp +driver:: + + # insmod lp parport=0,2 + +or on the LILO command line:: + + lp=parport0 lp=parport2 + +Both the above examples would inform lp that you want ``/dev/lp0`` to be +the first parallel port, and /dev/lp1 to be the **third** parallel port, +with no lp device associated with the second port (parport1). Note +that this is different to the way older kernels worked; there used to +be a static association between the I/O port address and the device +name, so ``/dev/lp0`` was always the port at 0x3bc. This is no longer the +case - if you only have one port, it will default to being ``/dev/lp0``, +regardless of base address. + +Also: + + * If you selected the IEEE 1284 support at compile time, you can say + ``lp=auto`` on the kernel command line, and lp will create devices + only for those ports that seem to have printers attached. + + * If you give PLIP the ``timid`` parameter, either with ``plip=timid`` on + the command line, or with ``insmod plip timid=1`` when using modules, + it will avoid any ports that seem to be in use by other devices. + + * IRQ autoprobing works only for a few port types at the moment. + +Reporting printer problems with parport +======================================= + +If you are having problems printing, please go through these steps to +try to narrow down where the problem area is. + +When reporting problems with parport, really you need to give all of +the messages that ``parport_pc`` spits out when it initialises. There are +several code paths: + +- polling +- interrupt-driven, protocol in software +- interrupt-driven, protocol in hardware using PIO +- interrupt-driven, protocol in hardware using DMA + +The kernel messages that ``parport_pc`` logs give an indication of which +code path is being used. (They could be a lot better actually..) + +For normal printer protocol, having IEEE 1284 modes enabled or not +should not make a difference. + +To turn off the 'protocol in hardware' code paths, disable +``CONFIG_PARPORT_PC_FIFO``. Note that when they are enabled they are not +necessarily **used**; it depends on whether the hardware is available, +enabled by the BIOS, and detected by the driver. + +So, to start with, disable ``CONFIG_PARPORT_PC_FIFO``, and load ``parport_pc`` +with ``irq=none``. See if printing works then. It really should, +because this is the simplest code path. + +If that works fine, try with ``io=0x378 irq=7`` (adjust for your +hardware), to make it use interrupt-driven in-software protocol. + +If **that** works fine, then one of the hardware modes isn't working +right. Enable ``CONFIG_FIFO`` (no, it isn't a module option, +and yes, it should be), set the port to ECP mode in the BIOS and note +the DMA channel, and try with:: + + io=0x378 irq=7 dma=none (for PIO) + io=0x378 irq=7 dma=3 (for DMA) + +---------- + +philb@gnu.org +tim@cyberelk.net diff --git a/Documentation/ramoops.txt b/Documentation/admin-guide/ramoops.rst index 26b9f31..fe95c02 100644 --- a/Documentation/ramoops.txt +++ b/Documentation/admin-guide/ramoops.rst @@ -5,34 +5,37 @@ Sergiu Iordache <sergiu@chromium.org> Updated: 17 November 2011 -0. Introduction +Introduction +------------ Ramoops is an oops/panic logger that writes its logs to RAM before the system crashes. It works by logging oopses and panics in a circular buffer. Ramoops needs a system with persistent RAM so that the content of that area can survive after a restart. -1. Ramoops concepts +Ramoops concepts +---------------- Ramoops uses a predefined memory area to store the dump. The start and size and type of the memory area are set using three variables: - * "mem_address" for the start - * "mem_size" for the size. The memory size will be rounded down to a - power of two. - * "mem_type" to specifiy if the memory type (default is pgprot_writecombine). - -Typically the default value of mem_type=0 should be used as that sets the pstore -mapping to pgprot_writecombine. Setting mem_type=1 attempts to use -pgprot_noncached, which only works on some platforms. This is because pstore + + * ``mem_address`` for the start + * ``mem_size`` for the size. The memory size will be rounded down to a + power of two. + * ``mem_type`` to specifiy if the memory type (default is pgprot_writecombine). + +Typically the default value of ``mem_type=0`` should be used as that sets the pstore +mapping to pgprot_writecombine. Setting ``mem_type=1`` attempts to use +``pgprot_noncached``, which only works on some platforms. This is because pstore depends on atomic operations. At least on ARM, pgprot_noncached causes the memory to be mapped strongly ordered, and atomic operations on strongly ordered memory are implementation defined, and won't work on many ARMs such as omaps. -The memory area is divided into "record_size" chunks (also rounded down to -power of two) and each oops/panic writes a "record_size" chunk of +The memory area is divided into ``record_size`` chunks (also rounded down to +power of two) and each oops/panic writes a ``record_size`` chunk of information. -Dumping both oopses and panics can be done by setting 1 in the "dump_oops" +Dumping both oopses and panics can be done by setting 1 in the ``dump_oops`` variable while setting 0 in that variable dumps only the panics. The module uses a counter to record multiple dumps but the counter gets reset @@ -43,7 +46,8 @@ This might be useful when a hardware reset was used to bring the machine back to life (i.e. a watchdog triggered). In such cases, RAM may be somewhat corrupt, but usually it is restorable. -2. Setting the parameters +Setting the parameters +---------------------- Setting the ramoops parameters can be done in several different manners: @@ -52,12 +56,13 @@ Setting the ramoops parameters can be done in several different manners: boot and then use the reserved memory for ramoops. For example, assuming a machine with > 128 MB of memory, the following kernel command line will tell the kernel to use only the first 128 MB of memory, and place ECC-protected - ramoops region at 128 MB boundary: - "mem=128M ramoops.mem_address=0x8000000 ramoops.ecc=1" + ramoops region at 128 MB boundary:: + + mem=128M ramoops.mem_address=0x8000000 ramoops.ecc=1 B. Use Device Tree bindings, as described in - Documentation/device-tree/bindings/reserved-memory/ramoops.txt. - For example: + ``Documentation/device-tree/bindings/reserved-memory/admin-guide/ramoops.rst``. + For example:: reserved-memory { #address-cells = <2>; @@ -73,60 +78,63 @@ Setting the ramoops parameters can be done in several different manners: }; C. Use a platform device and set the platform data. The parameters can then - be set through that platform data. An example of doing that is: + be set through that platform data. An example of doing that is:: -#include <linux/pstore_ram.h> -[...] + #include <linux/pstore_ram.h> + [...] -static struct ramoops_platform_data ramoops_data = { + static struct ramoops_platform_data ramoops_data = { .mem_size = <...>, .mem_address = <...>, .mem_type = <...>, .record_size = <...>, .dump_oops = <...>, .ecc = <...>, -}; + }; -static struct platform_device ramoops_dev = { + static struct platform_device ramoops_dev = { .name = "ramoops", .dev = { .platform_data = &ramoops_data, }, -}; + }; -[... inside a function ...] -int ret; + [... inside a function ...] + int ret; -ret = platform_device_register(&ramoops_dev); -if (ret) { + ret = platform_device_register(&ramoops_dev); + if (ret) { printk(KERN_ERR "unable to register platform device\n"); return ret; -} + } You can specify either RAM memory or peripheral devices' memory. However, when specifying RAM, be sure to reserve the memory by issuing memblock_reserve() -very early in the architecture code, e.g.: +very early in the architecture code, e.g.:: -#include <linux/memblock.h> + #include <linux/memblock.h> -memblock_reserve(ramoops_data.mem_address, ramoops_data.mem_size); + memblock_reserve(ramoops_data.mem_address, ramoops_data.mem_size); -3. Dump format +Dump format +----------- -The data dump begins with a header, currently defined as "====" followed by a +The data dump begins with a header, currently defined as ``====`` followed by a timestamp and a new line. The dump then continues with the actual data. -4. Reading the data +Reading the data +---------------- The dump data can be read from the pstore filesystem. The format for these -files is "dmesg-ramoops-N", where N is the record number in memory. To delete +files is ``dmesg-ramoops-N``, where N is the record number in memory. To delete a stored record from RAM, simply unlink the respective pstore file. -5. Persistent function tracing +Persistent function tracing +--------------------------- Persistent function tracing might be useful for debugging software or hardware -related hangs. The functions call chain log is stored in a "ftrace-ramoops" -file. Here is an example of usage: +related hangs. The functions call chain log is stored in a ``ftrace-ramoops`` +file. Here is an example of usage:: # mount -t debugfs debugfs /sys/kernel/debug/ # echo 1 > /sys/kernel/debug/pstore/record_ftrace diff --git a/REPORTING-BUGS b/Documentation/admin-guide/reporting-bugs.rst index 914baf9..0c0f269 100644 --- a/REPORTING-BUGS +++ b/Documentation/admin-guide/reporting-bugs.rst @@ -1,3 +1,8 @@ +.. _reportingbugs: + +Reporting bugs +++++++++++++++ + Background ========== @@ -50,12 +55,13 @@ maintainer replies to you, make sure to 'Reply-all' in order to keep the public mailing list(s) in the email thread. If you know which driver is causing issues, you can pass one of the driver -files to the get_maintainer.pl script: +files to the get_maintainer.pl script:: + perl scripts/get_maintainer.pl -f <filename> If it is a security bug, please copy the Security Contact listed in the MAINTAINERS file. They can help coordinate bugfix and disclosure. See -Documentation/SecurityBugs for more information. +:ref:`Documentation/admin-guide/security-bugs.rst <securitybugs>` for more information. If you can't figure out which subsystem caused the issue, you should file a bug in kernel.org bugzilla and send email to @@ -69,8 +75,9 @@ Tips for reporting bugs If you haven't reported a bug before, please read: -http://www.chiark.greenend.org.uk/~sgtatham/bugs.html -http://www.catb.org/esr/faqs/smart-questions.html + http://www.chiark.greenend.org.uk/~sgtatham/bugs.html + + http://www.catb.org/esr/faqs/smart-questions.html It's REALLY important to report bugs that seem unrelated as separate email threads or separate bugzilla entries. If you report several unrelated @@ -87,7 +94,7 @@ step-by-step instructions for how a user can trigger the bug. If the failure includes an "OOPS:", take a picture of the screen, capture a netconsole trace, or type the message from your screen into the bug -report. Please read "Documentation/oops-tracing.txt" before posting your +report. Please read "Documentation/admin-guide/oops-tracing.rst" before posting your bug report. This explains what you should do with the "Oops" information to make it useful to the recipient. @@ -99,34 +106,34 @@ relevant to your bug, feel free to exclude it. First run the ver_linux script included as scripts/ver_linux, which reports the version of some important subsystems. Run this script with -the command "sh scripts/ver_linux". +the command ``sh scripts/ver_linux``. Use that information to fill in all fields of the bug report form, and post it to the mailing list with a subject of "PROBLEM: <one line -summary from [1.]>" for easy identification by the developers. - -[1.] One line summary of the problem: -[2.] Full description of the problem/report: -[3.] Keywords (i.e., modules, networking, kernel): -[4.] Kernel information -[4.1.] Kernel version (from /proc/version): -[4.2.] Kernel .config file: -[5.] Most recent kernel version which did not have the bug: -[6.] Output of Oops.. message (if applicable) with symbolic information - resolved (see Documentation/oops-tracing.txt) -[7.] A small shell script or example program which triggers the - problem (if possible) -[8.] Environment -[8.1.] Software (add the output of the ver_linux script here) -[8.2.] Processor information (from /proc/cpuinfo): -[8.3.] Module information (from /proc/modules): -[8.4.] Loaded driver and hardware information (/proc/ioports, /proc/iomem) -[8.5.] PCI information ('lspci -vvv' as root) -[8.6.] SCSI information (from /proc/scsi/scsi) -[8.7.] Other information that might be relevant to the problem - (please look in /proc and include all information that you - think to be relevant): -[X.] Other notes, patches, fixes, workarounds: +summary from [1.]>" for easy identification by the developers:: + + [1.] One line summary of the problem: + [2.] Full description of the problem/report: + [3.] Keywords (i.e., modules, networking, kernel): + [4.] Kernel information + [4.1.] Kernel version (from /proc/version): + [4.2.] Kernel .config file: + [5.] Most recent kernel version which did not have the bug: + [6.] Output of Oops.. message (if applicable) with symbolic information + resolved (see Documentation/admin-guide/oops-tracing.rst) + [7.] A small shell script or example program which triggers the + problem (if possible) + [8.] Environment + [8.1.] Software (add the output of the ver_linux script here) + [8.2.] Processor information (from /proc/cpuinfo): + [8.3.] Module information (from /proc/modules): + [8.4.] Loaded driver and hardware information (/proc/ioports, /proc/iomem) + [8.5.] PCI information ('lspci -vvv' as root) + [8.6.] SCSI information (from /proc/scsi/scsi) + [8.7.] Other information that might be relevant to the problem + (please look in /proc and include all information that you + think to be relevant): + [X.] Other notes, patches, fixes, workarounds: Follow up @@ -153,7 +160,8 @@ Expectations for kernel maintainers Linux kernel maintainers are busy, overworked human beings. Some times they may not be able to address your bug in a day, a week, or two weeks. If they don't answer your email, they may be on vacation, or at a Linux -conference. Check the conference schedule at LWN.net for more info: +conference. Check the conference schedule at https://LWN.net for more info: + https://lwn.net/Calendar/ In general, kernel maintainers take 1 to 5 business days to respond to diff --git a/Documentation/SecurityBugs b/Documentation/admin-guide/security-bugs.rst index 342d769..4f7414c 100644 --- a/Documentation/SecurityBugs +++ b/Documentation/admin-guide/security-bugs.rst @@ -8,8 +8,8 @@ like to know when a security bug is found so that it can be fixed and disclosed as quickly as possible. Please report security bugs to the Linux kernel security team. -1) Contact ----------- +Contact +------- The Linux kernel security team can be contacted by email at <security@kernel.org>. This is a private list of security officers @@ -19,12 +19,12 @@ area maintainers to understand and fix the security vulnerability. As it is with any bug, the more information provided the easier it will be to diagnose and fix. Please review the procedure outlined in -REPORTING-BUGS if you are unclear about what information is helpful. +admin-guide/reporting-bugs.rst if you are unclear about what information is helpful. Any exploit code is very helpful and will not be released without consent from the reporter unless it has already been made public. -2) Disclosure -------------- +Disclosure +---------- The goal of the Linux kernel security team is to work with the bug submitter to bug resolution as well as disclosure. We prefer @@ -39,8 +39,8 @@ disclosure is from immediate (esp. if it's already publicly known) to a few weeks. As a basic default policy, we expect report date to disclosure date to be on the order of 7 days. -3) Non-disclosure agreements ----------------------------- +Non-disclosure agreements +------------------------- The Linux kernel security team is not a formal body and therefore unable to enter any non-disclosure agreements. diff --git a/Documentation/serial-console.txt b/Documentation/admin-guide/serial-console.rst index 9a7bc8b..a8d1e36 100644 --- a/Documentation/serial-console.txt +++ b/Documentation/admin-guide/serial-console.rst @@ -1,15 +1,21 @@ - Linux Serial Console +.. _serial_console: + +Linux Serial Console +==================== To use a serial port as console you need to compile the support into your kernel - by default it is not compiled in. For PC style serial ports -it's the config option next to "Standard/generic (dumb) serial support". +it's the config option next to menu option: + +:menuselection:`Character devices --> Serial drivers --> 8250/16550 and compatible serial support --> Console on 8250/16550 and compatible serial port` + You must compile serial support into the kernel and not as a module. It is possible to specify multiple devices for console output. You can define a new kernel command line option to select which device(s) to use for console output. -The format of this option is: +The format of this option is:: console=device,options @@ -28,11 +34,11 @@ The format of this option is: You can specify multiple console= options on the kernel command line. Output will appear on all of them. The last device will be used when -you open /dev/console. So, for example: +you open ``/dev/console``. So, for example:: console=ttyS1,9600 console=tty0 -defines that opening /dev/console will get you the current foreground +defines that opening ``/dev/console`` will get you the current foreground virtual console, and kernel messages will appear on both the VGA console and the 2nd serial port (ttyS1 or COM2) at 9600 baud. @@ -44,61 +50,61 @@ first looks for a VGA card and then for a serial port. So if you don't have a VGA card in your system the first serial port will automatically become the console. -You will need to create a new device to use /dev/console. The official -/dev/console is now character device 5,1. +You will need to create a new device to use ``/dev/console``. The official +``/dev/console`` is now character device 5,1. (You can also use a network device as a console. See -Documentation/networking/netconsole.txt for information on that.) +``Documentation/networking/netconsole.txt`` for information on that.) -Here's an example that will use /dev/ttyS1 (COM2) as the console. +Here's an example that will use ``/dev/ttyS1`` (COM2) as the console. Replace the sample values as needed. -1. Create /dev/console (real console) and /dev/tty0 (master virtual - console): +1. Create ``/dev/console`` (real console) and ``/dev/tty0`` (master virtual + console):: - cd /dev - rm -f console tty0 - mknod -m 622 console c 5 1 - mknod -m 622 tty0 c 4 0 + cd /dev + rm -f console tty0 + mknod -m 622 console c 5 1 + mknod -m 622 tty0 c 4 0 2. LILO can also take input from a serial device. This is a very useful option. To tell LILO to use the serial port: - In lilo.conf (global section): + In lilo.conf (global section):: - serial = 1,9600n8 (ttyS1, 9600 bd, no parity, 8 bits) + serial = 1,9600n8 (ttyS1, 9600 bd, no parity, 8 bits) 3. Adjust to kernel flags for the new kernel, - again in lilo.conf (kernel section) + again in lilo.conf (kernel section):: - append = "console=ttyS1,9600" + append = "console=ttyS1,9600" 4. Make sure a getty runs on the serial port so that you can login to it once the system is done booting. This is done by adding a line - like this to /etc/inittab (exact syntax depends on your getty): + like this to ``/etc/inittab`` (exact syntax depends on your getty):: - S1:23:respawn:/sbin/getty -L ttyS1 9600 vt100 + S1:23:respawn:/sbin/getty -L ttyS1 9600 vt100 -5. Init and /etc/ioctl.save +5. Init and ``/etc/ioctl.save`` - Sysvinit remembers its stty settings in a file in /etc, called - `/etc/ioctl.save'. REMOVE THIS FILE before using the serial + Sysvinit remembers its stty settings in a file in ``/etc``, called + ``/etc/ioctl.save``. REMOVE THIS FILE before using the serial console for the first time, because otherwise init will probably set the baudrate to 38400 (baudrate of the virtual console). -6. /dev/console and X +6. ``/dev/console`` and X Programs that want to do something with the virtual console usually - open /dev/console. If you have created the new /dev/console device, + open ``/dev/console``. If you have created the new ``/dev/console`` device, and your console is NOT the virtual console some programs will fail. Those are programs that want to access the VT interface, and use - /dev/console instead of /dev/tty0. Some of those programs are: + ``/dev/console instead of /dev/tty0``. Some of those programs are:: - Xfree86, svgalib, gpm, SVGATextMode + Xfree86, svgalib, gpm, SVGATextMode It should be fixed in modern versions of these programs though. - Note that if you boot without a console= option (or with - console=/dev/tty0), /dev/console is the same as /dev/tty0. In that - case everything will still work. + Note that if you boot without a ``console=`` option (or with + ``console=/dev/tty0``), ``/dev/console`` is the same as ``/dev/tty0``. + In that case everything will still work. 7. Thanks diff --git a/Documentation/admin-guide/sysfs-rules.rst b/Documentation/admin-guide/sysfs-rules.rst new file mode 100644 index 0000000..04bdd52 --- /dev/null +++ b/Documentation/admin-guide/sysfs-rules.rst @@ -0,0 +1,192 @@ +Rules on how to access information in the Linux kernel sysfs +============================================================ + +The kernel-exported sysfs exports internal kernel implementation details +and depends on internal kernel structures and layout. It is agreed upon +by the kernel developers that the Linux kernel does not provide a stable +internal API. Therefore, there are aspects of the sysfs interface that +may not be stable across kernel releases. + +To minimize the risk of breaking users of sysfs, which are in most cases +low-level userspace applications, with a new kernel release, the users +of sysfs must follow some rules to use an as-abstract-as-possible way to +access this filesystem. The current udev and HAL programs already +implement this and users are encouraged to plug, if possible, into the +abstractions these programs provide instead of accessing sysfs directly. + +But if you really do want or need to access sysfs directly, please follow +the following rules and then your programs should work with future +versions of the sysfs interface. + +- Do not use libsysfs + It makes assumptions about sysfs which are not true. Its API does not + offer any abstraction, it exposes all the kernel driver-core + implementation details in its own API. Therefore it is not better than + reading directories and opening the files yourself. + Also, it is not actively maintained, in the sense of reflecting the + current kernel development. The goal of providing a stable interface + to sysfs has failed; it causes more problems than it solves. It + violates many of the rules in this document. + +- sysfs is always at ``/sys`` + Parsing ``/proc/mounts`` is a waste of time. Other mount points are a + system configuration bug you should not try to solve. For test cases, + possibly support a ``SYSFS_PATH`` environment variable to overwrite the + application's behavior, but never try to search for sysfs. Never try + to mount it, if you are not an early boot script. + +- devices are only "devices" + There is no such thing like class-, bus-, physical devices, + interfaces, and such that you can rely on in userspace. Everything is + just simply a "device". Class-, bus-, physical, ... types are just + kernel implementation details which should not be expected by + applications that look for devices in sysfs. + + The properties of a device are: + + - devpath (``/devices/pci0000:00/0000:00:1d.1/usb2/2-2/2-2:1.0``) + + - identical to the DEVPATH value in the event sent from the kernel + at device creation and removal + - the unique key to the device at that point in time + - the kernel's path to the device directory without the leading + ``/sys``, and always starting with a slash + - all elements of a devpath must be real directories. Symlinks + pointing to /sys/devices must always be resolved to their real + target and the target path must be used to access the device. + That way the devpath to the device matches the devpath of the + kernel used at event time. + - using or exposing symlink values as elements in a devpath string + is a bug in the application + + - kernel name (``sda``, ``tty``, ``0000:00:1f.2``, ...) + + - a directory name, identical to the last element of the devpath + - applications need to handle spaces and characters like ``!`` in + the name + + - subsystem (``block``, ``tty``, ``pci``, ...) + + - simple string, never a path or a link + - retrieved by reading the "subsystem"-link and using only the + last element of the target path + + - driver (``tg3``, ``ata_piix``, ``uhci_hcd``) + + - a simple string, which may contain spaces, never a path or a + link + - it is retrieved by reading the "driver"-link and using only the + last element of the target path + - devices which do not have "driver"-link just do not have a + driver; copying the driver value in a child device context is a + bug in the application + + - attributes + + - the files in the device directory or files below subdirectories + of the same device directory + - accessing attributes reached by a symlink pointing to another device, + like the "device"-link, is a bug in the application + + Everything else is just a kernel driver-core implementation detail + that should not be assumed to be stable across kernel releases. + +- Properties of parent devices never belong into a child device. + Always look at the parent devices themselves for determining device + context properties. If the device ``eth0`` or ``sda`` does not have a + "driver"-link, then this device does not have a driver. Its value is empty. + Never copy any property of the parent-device into a child-device. Parent + device properties may change dynamically without any notice to the + child device. + +- Hierarchy in a single device tree + There is only one valid place in sysfs where hierarchy can be examined + and this is below: ``/sys/devices.`` + It is planned that all device directories will end up in the tree + below this directory. + +- Classification by subsystem + There are currently three places for classification of devices: + ``/sys/block,`` ``/sys/class`` and ``/sys/bus.`` It is planned that these will + not contain any device directories themselves, but only flat lists of + symlinks pointing to the unified ``/sys/devices`` tree. + All three places have completely different rules on how to access + device information. It is planned to merge all three + classification directories into one place at ``/sys/subsystem``, + following the layout of the bus directories. All buses and + classes, including the converted block subsystem, will show up + there. + The devices belonging to a subsystem will create a symlink in the + "devices" directory at ``/sys/subsystem/<name>/devices``, + + If ``/sys/subsystem`` exists, ``/sys/bus``, ``/sys/class`` and ``/sys/block`` + can be ignored. If it does not exist, you always have to scan all three + places, as the kernel is free to move a subsystem from one place to + the other, as long as the devices are still reachable by the same + subsystem name. + + Assuming ``/sys/class/<subsystem>`` and ``/sys/bus/<subsystem>``, or + ``/sys/block`` and ``/sys/class/block`` are not interchangeable is a bug in + the application. + +- Block + The converted block subsystem at ``/sys/class/block`` or + ``/sys/subsystem/block`` will contain the links for disks and partitions + at the same level, never in a hierarchy. Assuming the block subsystem to + contain only disks and not partition devices in the same flat list is + a bug in the application. + +- "device"-link and <subsystem>:<kernel name>-links + Never depend on the "device"-link. The "device"-link is a workaround + for the old layout, where class devices are not created in + ``/sys/devices/`` like the bus devices. If the link-resolving of a + device directory does not end in ``/sys/devices/``, you can use the + "device"-link to find the parent devices in ``/sys/devices/``, That is the + single valid use of the "device"-link; it must never appear in any + path as an element. Assuming the existence of the "device"-link for + a device in ``/sys/devices/`` is a bug in the application. + Accessing ``/sys/class/net/eth0/device`` is a bug in the application. + + Never depend on the class-specific links back to the ``/sys/class`` + directory. These links are also a workaround for the design mistake + that class devices are not created in ``/sys/devices.`` If a device + directory does not contain directories for child devices, these links + may be used to find the child devices in ``/sys/class.`` That is the single + valid use of these links; they must never appear in any path as an + element. Assuming the existence of these links for devices which are + real child device directories in the ``/sys/devices`` tree is a bug in + the application. + + It is planned to remove all these links when all class device + directories live in ``/sys/devices.`` + +- Position of devices along device chain can change. + Never depend on a specific parent device position in the devpath, + or the chain of parent devices. The kernel is free to insert devices into + the chain. You must always request the parent device you are looking for + by its subsystem value. You need to walk up the chain until you find + the device that matches the expected subsystem. Depending on a specific + position of a parent device or exposing relative paths using ``../`` to + access the chain of parents is a bug in the application. + +- When reading and writing sysfs device attribute files, avoid dependency + on specific error codes wherever possible. This minimizes coupling to + the error handling implementation within the kernel. + + In general, failures to read or write sysfs device attributes shall + propagate errors wherever possible. Common errors include, but are not + limited to: + + ``-EIO``: The read or store operation is not supported, typically + returned by the sysfs system itself if the read or store pointer + is ``NULL``. + + ``-ENXIO``: The read or store operation failed + + Error codes will not be changed without good reason, and should a change + to error codes result in user-space breakage, it will be fixed, or the + the offending change will be reverted. + + Userspace applications can, however, expect the format and contents of + the attribute files to remain consistent in the absence of a version + attribute change in the context of a given attribute. diff --git a/Documentation/admin-guide/sysrq.rst b/Documentation/admin-guide/sysrq.rst new file mode 100644 index 0000000..d1712ea --- /dev/null +++ b/Documentation/admin-guide/sysrq.rst @@ -0,0 +1,289 @@ +Linux Magic System Request Key Hacks +==================================== + +Documentation for sysrq.c + +What is the magic SysRq key? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +It is a 'magical' key combo you can hit which the kernel will respond to +regardless of whatever else it is doing, unless it is completely locked up. + +How do I enable the magic SysRq key? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +You need to say "yes" to 'Magic SysRq key (CONFIG_MAGIC_SYSRQ)' when +configuring the kernel. When running a kernel with SysRq compiled in, +/proc/sys/kernel/sysrq controls the functions allowed to be invoked via +the SysRq key. The default value in this file is set by the +CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE config symbol, which itself defaults +to 1. Here is the list of possible values in /proc/sys/kernel/sysrq: + + - 0 - disable sysrq completely + - 1 - enable all functions of sysrq + - >1 - bitmask of allowed sysrq functions (see below for detailed function + description):: + + 2 = 0x2 - enable control of console logging level + 4 = 0x4 - enable control of keyboard (SAK, unraw) + 8 = 0x8 - enable debugging dumps of processes etc. + 16 = 0x10 - enable sync command + 32 = 0x20 - enable remount read-only + 64 = 0x40 - enable signalling of processes (term, kill, oom-kill) + 128 = 0x80 - allow reboot/poweroff + 256 = 0x100 - allow nicing of all RT tasks + +You can set the value in the file by the following command:: + + echo "number" >/proc/sys/kernel/sysrq + +The number may be written here either as decimal or as hexadecimal +with the 0x prefix. CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE must always be +written in hexadecimal. + +Note that the value of ``/proc/sys/kernel/sysrq`` influences only the invocation +via a keyboard. Invocation of any operation via ``/proc/sysrq-trigger`` is +always allowed (by a user with admin privileges). + +How do I use the magic SysRq key? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +On x86 - You press the key combo :kbd:`ALT-SysRq-<command key>`. + +.. note:: + Some + keyboards may not have a key labeled 'SysRq'. The 'SysRq' key is + also known as the 'Print Screen' key. Also some keyboards cannot + handle so many keys being pressed at the same time, so you might + have better luck with press :kbd:`Alt`, press :kbd:`SysRq`, + release :kbd:`SysRq`, press :kbd:`<command key>`, release everything. + +On SPARC - You press :kbd:`ALT-STOP-<command key>`, I believe. + +On the serial console (PC style standard serial ports only) + You send a ``BREAK``, then within 5 seconds a command key. Sending + ``BREAK`` twice is interpreted as a normal BREAK. + +On PowerPC + Press :kbd:`ALT - Print Screen` (or :kbd:`F13`) - :kbd:`<command key>`, + :kbd:`Print Screen` (or :kbd:`F13`) - :kbd:`<command key>` may suffice. + +On other + If you know of the key combos for other architectures, please + let me know so I can add them to this section. + +On all + write a character to /proc/sysrq-trigger. e.g.:: + + echo t > /proc/sysrq-trigger + +What are the 'command' keys? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +=========== =================================================================== +Command Function +=========== =================================================================== +``b`` Will immediately reboot the system without syncing or unmounting + your disks. + +``c`` Will perform a system crash by a NULL pointer dereference. + A crashdump will be taken if configured. + +``d`` Shows all locks that are held. + +``e`` Send a SIGTERM to all processes, except for init. + +``f`` Will call the oom killer to kill a memory hog process, but do not + panic if nothing can be killed. + +``g`` Used by kgdb (kernel debugger) + +``h`` Will display help (actually any other key than those listed + here will display help. but ``h`` is easy to remember :-) + +``i`` Send a SIGKILL to all processes, except for init. + +``j`` Forcibly "Just thaw it" - filesystems frozen by the FIFREEZE ioctl. + +``k`` Secure Access Key (SAK) Kills all programs on the current virtual + console. NOTE: See important comments below in SAK section. + +``l`` Shows a stack backtrace for all active CPUs. + +``m`` Will dump current memory info to your console. + +``n`` Used to make RT tasks nice-able + +``o`` Will shut your system off (if configured and supported). + +``p`` Will dump the current registers and flags to your console. + +``q`` Will dump per CPU lists of all armed hrtimers (but NOT regular + timer_list timers) and detailed information about all + clockevent devices. + +``r`` Turns off keyboard raw mode and sets it to XLATE. + +``s`` Will attempt to sync all mounted filesystems. + +``t`` Will dump a list of current tasks and their information to your + console. + +``u`` Will attempt to remount all mounted filesystems read-only. + +``v`` Forcefully restores framebuffer console +``v`` Causes ETM buffer dump [ARM-specific] + +``w`` Dumps tasks that are in uninterruptable (blocked) state. + +``x`` Used by xmon interface on ppc/powerpc platforms. + Show global PMU Registers on sparc64. + Dump all TLB entries on MIPS. + +``y`` Show global CPU Registers [SPARC-64 specific] + +``z`` Dump the ftrace buffer + +``0``-``9`` Sets the console log level, controlling which kernel messages + will be printed to your console. (``0``, for example would make + it so that only emergency messages like PANICs or OOPSes would + make it to your console.) +=========== =================================================================== + +Okay, so what can I use them for? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Well, unraw(r) is very handy when your X server or a svgalib program crashes. + +sak(k) (Secure Access Key) is useful when you want to be sure there is no +trojan program running at console which could grab your password +when you would try to login. It will kill all programs on given console, +thus letting you make sure that the login prompt you see is actually +the one from init, not some trojan program. + +.. important:: + + In its true form it is not a true SAK like the one in a + c2 compliant system, and it should not be mistaken as + such. + +It seems others find it useful as (System Attention Key) which is +useful when you want to exit a program that will not let you switch consoles. +(For example, X or a svgalib program.) + +``reboot(b)`` is good when you're unable to shut down. But you should also +``sync(s)`` and ``umount(u)`` first. + +``crash(c)`` can be used to manually trigger a crashdump when the system is hung. +Note that this just triggers a crash if there is no dump mechanism available. + +``sync(s)`` is great when your system is locked up, it allows you to sync your +disks and will certainly lessen the chance of data loss and fscking. Note +that the sync hasn't taken place until you see the "OK" and "Done" appear +on the screen. (If the kernel is really in strife, you may not ever get the +OK or Done message...) + +``umount(u)`` is basically useful in the same ways as ``sync(s)``. I generally +``sync(s)``, ``umount(u)``, then ``reboot(b)`` when my system locks. It's saved +me many a fsck. Again, the unmount (remount read-only) hasn't taken place until +you see the "OK" and "Done" message appear on the screen. + +The loglevels ``0``-``9`` are useful when your console is being flooded with +kernel messages you do not want to see. Selecting ``0`` will prevent all but +the most urgent kernel messages from reaching your console. (They will +still be logged if syslogd/klogd are alive, though.) + +``term(e)`` and ``kill(i)`` are useful if you have some sort of runaway process +you are unable to kill any other way, especially if it's spawning other +processes. + +"just thaw ``it(j)``" is useful if your system becomes unresponsive due to a +frozen (probably root) filesystem via the FIFREEZE ioctl. + +Sometimes SysRq seems to get 'stuck' after using it, what can I do? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +That happens to me, also. I've found that tapping shift, alt, and control +on both sides of the keyboard, and hitting an invalid sysrq sequence again +will fix the problem. (i.e., something like :kbd:`alt-sysrq-z`). Switching to +another virtual console (:kbd:`ALT+Fn`) and then back again should also help. + +I hit SysRq, but nothing seems to happen, what's wrong? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +There are some keyboards that produce a different keycode for SysRq than the +pre-defined value of 99 (see ``KEY_SYSRQ`` in ``include/linux/input.h``), or +which don't have a SysRq key at all. In these cases, run ``showkey -s`` to find +an appropriate scancode sequence, and use ``setkeycodes <sequence> 99`` to map +this sequence to the usual SysRq code (e.g., ``setkeycodes e05b 99``). It's +probably best to put this command in a boot script. Oh, and by the way, you +exit ``showkey`` by not typing anything for ten seconds. + +I want to add SysRQ key events to a module, how does it work? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +In order to register a basic function with the table, you must first include +the header ``include/linux/sysrq.h``, this will define everything else you need. +Next, you must create a ``sysrq_key_op`` struct, and populate it with A) the key +handler function you will use, B) a help_msg string, that will print when SysRQ +prints help, and C) an action_msg string, that will print right before your +handler is called. Your handler must conform to the prototype in 'sysrq.h'. + +After the ``sysrq_key_op`` is created, you can call the kernel function +``register_sysrq_key(int key, struct sysrq_key_op *op_p);`` this will +register the operation pointed to by ``op_p`` at table key 'key', +if that slot in the table is blank. At module unload time, you must call +the function ``unregister_sysrq_key(int key, struct sysrq_key_op *op_p)``, which +will remove the key op pointed to by 'op_p' from the key 'key', if and only if +it is currently registered in that slot. This is in case the slot has been +overwritten since you registered it. + +The Magic SysRQ system works by registering key operations against a key op +lookup table, which is defined in 'drivers/tty/sysrq.c'. This key table has +a number of operations registered into it at compile time, but is mutable, +and 2 functions are exported for interface to it:: + + register_sysrq_key and unregister_sysrq_key. + +Of course, never ever leave an invalid pointer in the table. I.e., when +your module that called register_sysrq_key() exits, it must call +unregister_sysrq_key() to clean up the sysrq key table entry that it used. +Null pointers in the table are always safe. :) + +If for some reason you feel the need to call the handle_sysrq function from +within a function called by handle_sysrq, you must be aware that you are in +a lock (you are also in an interrupt handler, which means don't sleep!), so +you must call ``__handle_sysrq_nolock`` instead. + +When I hit a SysRq key combination only the header appears on the console? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Sysrq output is subject to the same console loglevel control as all +other console output. This means that if the kernel was booted 'quiet' +as is common on distro kernels the output may not appear on the actual +console, even though it will appear in the dmesg buffer, and be accessible +via the dmesg command and to the consumers of ``/proc/kmsg``. As a specific +exception the header line from the sysrq command is passed to all console +consumers as if the current loglevel was maximum. If only the header +is emitted it is almost certain that the kernel loglevel is too low. +Should you require the output on the console channel then you will need +to temporarily up the console loglevel using :kbd:`alt-sysrq-8` or:: + + echo 8 > /proc/sysrq-trigger + +Remember to return the loglevel to normal after triggering the sysrq +command you are interested in. + +I have more questions, who can I ask? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Just ask them on the linux-kernel mailing list: + linux-kernel@vger.kernel.org + +Credits +~~~~~~~ + +Written by Mydraal <vulpyne@vulpyne.net> +Updated by Adam Sulmicki <adam@cfar.umd.edu> +Updated by Jeremy M. Dolan <jmd@turbogeek.org> 2001/01/28 10:15:59 +Added to by Crutcher Dunnavant <crutcher+kernel@datastacks.com> diff --git a/Documentation/unicode.txt b/Documentation/admin-guide/unicode.rst index 4a33f81..4e5c3df 100644 --- a/Documentation/unicode.txt +++ b/Documentation/admin-guide/unicode.rst @@ -1,12 +1,16 @@ +Unicode support +=============== + Last update: 2005-01-17, version 1.4 This file is maintained by H. Peter Anvin <unicode@lanana.org> as part of the Linux Assigned Names And Numbers Authority (LANANA) project. The current version can be found at: - http://www.lanana.org/docs/unicode/unicode.txt + http://www.lanana.org/docs/unicode/admin-guide/unicode.rst - ------------------------ +Introdution +----------- The Linux kernel code has been rewritten to use Unicode to map characters to fonts. By downloading a single Unicode-to-font table, @@ -16,12 +20,14 @@ the font as indicated. This changes the semantics of the eight-bit character tables subtly. The four character tables are now: +=============== =============================== ================ Map symbol Map name Escape code (G0) - +=============== =============================== ================ LAT1_MAP Latin-1 (ISO 8859-1) ESC ( B GRAF_MAP DEC VT100 pseudographics ESC ( 0 IBMPC_MAP IBM code page 437 ESC ( U USER_MAP User defined ESC ( K +=============== =============================== ================ In particular, ESC ( U is no longer "straight to font", since the font might be completely different than the IBM character set. This @@ -55,10 +61,12 @@ In addition, the following characters not present in Unicode 1.1.4 have been defined; these are used by the DEC VT graphics map. [v1.2] THIS USE IS OBSOLETE AND SHOULD NO LONGER BE USED; PLEASE SEE BELOW. +====== ====================================== U+F800 DEC VT GRAPHICS HORIZONTAL LINE SCAN 1 U+F801 DEC VT GRAPHICS HORIZONTAL LINE SCAN 3 U+F803 DEC VT GRAPHICS HORIZONTAL LINE SCAN 7 U+F804 DEC VT GRAPHICS HORIZONTAL LINE SCAN 9 +====== ====================================== The DEC VT220 uses a 6x10 character matrix, and these characters form a smooth progression in the DEC VT graphics character set. I have @@ -74,10 +82,12 @@ keyboard symbols that are unlikely to ever be added to Unicode proper since they are horribly vendor-specific. This, of course, is an excellent example of horrible design. +====== ====================================== U+F810 KEYBOARD SYMBOL FLYING FLAG U+F811 KEYBOARD SYMBOL PULLDOWN MENU U+F812 KEYBOARD SYMBOL OPEN APPLE U+F813 KEYBOARD SYMBOL SOLID APPLE +====== ====================================== Klingon language support ------------------------ @@ -99,8 +109,10 @@ of the dingbats/symbols/forms type and this is a language, I have located it at the end, on a 16-cell boundary in keeping with standard Unicode practice. -NOTE: This range is now officially managed by the ConScript Unicode -Registry. The normative reference is at: +.. note:: + + This range is now officially managed by the ConScript Unicode + Registry. The normative reference is at: http://www.evertype.com/standards/csur/klingon.html @@ -112,6 +124,7 @@ However, since the set of symbols appear to be consistent throughout, with only the actual shapes being different, in keeping with standard Unicode practice these differences are considered font variants. +====== ======================================================= U+F8D0 KLINGON LETTER A U+F8D1 KLINGON LETTER B U+F8D2 KLINGON LETTER CH @@ -155,6 +168,7 @@ U+F8F9 KLINGON DIGIT NINE U+F8FD KLINGON COMMA U+F8FE KLINGON FULL STOP U+F8FF KLINGON SYMBOL FOR EMPIRE +====== ======================================================= Other Fictional and Artificial Scripts -------------------------------------- diff --git a/Documentation/admin-guide/vga-softcursor.rst b/Documentation/admin-guide/vga-softcursor.rst new file mode 100644 index 0000000..9eac674 --- /dev/null +++ b/Documentation/admin-guide/vga-softcursor.rst @@ -0,0 +1,66 @@ +Software cursor for VGA +======================= + +by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz> +and Martin Mares <mj@atrey.karlin.mff.cuni.cz> + +Linux now has some ability to manipulate cursor appearance. Normally, you +can set the size of hardware cursor (and also work around some ugly bugs in +those miserable Trident cards [#f1]_. You can now play a few new tricks: +you can make your cursor look + +like a non-blinking red block, make it inverse background of the character it's +over or to highlight that character and still choose whether the original +hardware cursor should remain visible or not. There may be other things I have +never thought of. + +The cursor appearance is controlled by a ``<ESC>[?1;2;3c`` escape sequence +where 1, 2 and 3 are parameters described below. If you omit any of them, +they will default to zeroes. + +first Parameter + specifies cursor size:: + + 0=default + 1=invisible + 2=underline, + ... + 8=full block + + 16 if you want the software cursor to be applied + + 32 if you want to always change the background color + + 64 if you dislike having the background the same as the + foreground. + + Highlights are ignored for the last two flags. + +second parameter + selects character attribute bits you want to change + (by simply XORing them with the value of this parameter). On standard + VGA, the high four bits specify background and the low four the + foreground. In both groups, low three bits set color (as in normal + color codes used by the console) and the most significant one turns + on highlight (or sometimes blinking -- it depends on the configuration + of your VGA). + +third parameter + consists of character attribute bits you want to set. + + Bit setting takes place before bit toggling, so you can simply clear a + bit by including it in both the set mask and the toggle mask. + +.. [#f1] see ``#define TRIDENT_GLITCH`` in ``drivers/video/vgacon.c``. + +Examples: +========= + +To get normal blinking underline, use:: + + echo -e '\033[?2c' + +To get blinking block, use:: + + echo -e '\033[?6c' + +To get red non-blinking block, use:: + + echo -e '\033[?17;0;64c' diff --git a/Documentation/arm/Booting b/Documentation/arm/Booting index 83c1df2..259f00a 100644 --- a/Documentation/arm/Booting +++ b/Documentation/arm/Booting @@ -51,7 +51,7 @@ As an alternative, the boot loader can pass the relevant 'console=' option to the kernel via the tagged lists specifying the port, and serial format options as described in - Documentation/kernel-parameters.txt. + Documentation/admin-guide/kernel-parameters.rst. 3. Detect the machine type diff --git a/Documentation/atomic_ops.txt b/Documentation/atomic_ops.txt index c9d1cac..7281bf9 100644 --- a/Documentation/atomic_ops.txt +++ b/Documentation/atomic_ops.txt @@ -16,7 +16,7 @@ will fail. Something like the following should suffice: typedef struct { long counter; } atomic_long_t; Historically, counter has been declared volatile. This is now discouraged. -See Documentation/volatile-considered-harmful.txt for the complete rationale. +See Documentation/process/volatile-considered-harmful.rst for the complete rationale. local_t is very similar to atomic_t. If the counter is per CPU and only updated by one CPU, local_t is probably more appropriate. Please see diff --git a/Documentation/basic_profiling.txt b/Documentation/basic_profiling.txt deleted file mode 100644 index 8764e9f..0000000 --- a/Documentation/basic_profiling.txt +++ /dev/null @@ -1,56 +0,0 @@ -These instructions are deliberately very basic. If you want something clever, -go read the real docs ;-) Please don't add more stuff, but feel free to -correct my mistakes ;-) (mbligh@aracnet.com) -Thanks to John Levon, Dave Hansen, et al. for help writing this. - -<test> is the thing you're trying to measure. -Make sure you have the correct System.map / vmlinux referenced! - -It is probably easiest to use "make install" for linux and hack -/sbin/installkernel to copy vmlinux to /boot, in addition to vmlinuz, -config, System.map, which are usually installed by default. - -Readprofile ------------ -A recent readprofile command is needed for 2.6, such as found in util-linux -2.12a, which can be downloaded from: - -http://www.kernel.org/pub/linux/utils/util-linux/ - -Most distributions will ship it already. - -Add "profile=2" to the kernel command line. - -clear readprofile -r - <test> -dump output readprofile -m /boot/System.map > captured_profile - -Oprofile --------- - -Get the source (see Changes for required version) from -http://oprofile.sourceforge.net/ and add "idle=poll" to the kernel command -line. - -Configure with CONFIG_PROFILING=y and CONFIG_OPROFILE=y & reboot on new kernel - -./configure --with-kernel-support -make install - -For superior results, be sure to enable the local APIC. If opreport sees -a 0Hz CPU, APIC was not on. Be aware that idle=poll may mean a performance -penalty. - -One time setup: - opcontrol --setup --vmlinux=/boot/vmlinux - -clear opcontrol --reset -start opcontrol --start - <test> -stop opcontrol --stop -dump output opreport > output_file - -To only report on the kernel, run opreport -l /boot/vmlinux > output_file - -A reset is needed to clear old statistics, which survive a reboot. - diff --git a/Documentation/binfmt_misc.txt b/Documentation/binfmt_misc.txt deleted file mode 100644 index ec83bbc..0000000 --- a/Documentation/binfmt_misc.txt +++ /dev/null @@ -1,131 +0,0 @@ - Kernel Support for miscellaneous (your favourite) Binary Formats v1.1 - ===================================================================== - -This Kernel feature allows you to invoke almost (for restrictions see below) -every program by simply typing its name in the shell. -This includes for example compiled Java(TM), Python or Emacs programs. - -To achieve this you must tell binfmt_misc which interpreter has to be invoked -with which binary. Binfmt_misc recognises the binary-type by matching some bytes -at the beginning of the file with a magic byte sequence (masking out specified -bits) you have supplied. Binfmt_misc can also recognise a filename extension -aka '.com' or '.exe'. - -First you must mount binfmt_misc: - mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc - -To actually register a new binary type, you have to set up a string looking like -:name:type:offset:magic:mask:interpreter:flags (where you can choose the ':' -upon your needs) and echo it to /proc/sys/fs/binfmt_misc/register. - -Here is what the fields mean: - - 'name' is an identifier string. A new /proc file will be created with this - name below /proc/sys/fs/binfmt_misc; cannot contain slashes '/' for obvious - reasons. - - 'type' is the type of recognition. Give 'M' for magic and 'E' for extension. - - 'offset' is the offset of the magic/mask in the file, counted in bytes. This - defaults to 0 if you omit it (i.e. you write ':name:type::magic...'). Ignored - when using filename extension matching. - - 'magic' is the byte sequence binfmt_misc is matching for. The magic string - may contain hex-encoded characters like \x0a or \xA4. Note that you must - escape any NUL bytes; parsing halts at the first one. In a shell environment - you might have to write \\x0a to prevent the shell from eating your \. - If you chose filename extension matching, this is the extension to be - recognised (without the '.', the \x0a specials are not allowed). Extension - matching is case sensitive, and slashes '/' are not allowed! - - 'mask' is an (optional, defaults to all 0xff) mask. You can mask out some - bits from matching by supplying a string like magic and as long as magic. - The mask is anded with the byte sequence of the file. Note that you must - escape any NUL bytes; parsing halts at the first one. Ignored when using - filename extension matching. - - 'interpreter' is the program that should be invoked with the binary as first - argument (specify the full path) - - 'flags' is an optional field that controls several aspects of the invocation - of the interpreter. It is a string of capital letters, each controls a - certain aspect. The following flags are supported - - 'P' - preserve-argv[0]. Legacy behavior of binfmt_misc is to overwrite - the original argv[0] with the full path to the binary. When this - flag is included, binfmt_misc will add an argument to the argument - vector for this purpose, thus preserving the original argv[0]. - e.g. If your interp is set to /bin/foo and you run `blah` (which is - in /usr/local/bin), then the kernel will execute /bin/foo with - argv[] set to ["/bin/foo", "/usr/local/bin/blah", "blah"]. The - interp has to be aware of this so it can execute /usr/local/bin/blah - with argv[] set to ["blah"]. - 'O' - open-binary. Legacy behavior of binfmt_misc is to pass the full path - of the binary to the interpreter as an argument. When this flag is - included, binfmt_misc will open the file for reading and pass its - descriptor as an argument, instead of the full path, thus allowing - the interpreter to execute non-readable binaries. This feature - should be used with care - the interpreter has to be trusted not to - emit the contents of the non-readable binary. - 'C' - credentials. Currently, the behavior of binfmt_misc is to calculate - the credentials and security token of the new process according to - the interpreter. When this flag is included, these attributes are - calculated according to the binary. It also implies the 'O' flag. - This feature should be used with care as the interpreter - will run with root permissions when a setuid binary owned by root - is run with binfmt_misc. - 'F' - fix binary. The usual behaviour of binfmt_misc is to spawn the - binary lazily when the misc format file is invoked. However, - this doesn't work very well in the face of mount namespaces and - changeroots, so the F mode opens the binary as soon as the - emulation is installed and uses the opened image to spawn the - emulator, meaning it is always available once installed, - regardless of how the environment changes. - - -There are some restrictions: - - the whole register string may not exceed 1920 characters - - the magic must reside in the first 128 bytes of the file, i.e. - offset+size(magic) has to be less than 128 - - the interpreter string may not exceed 127 characters - -To use binfmt_misc you have to mount it first. You can mount it with -"mount -t binfmt_misc none /proc/sys/fs/binfmt_misc" command, or you can add -a line "none /proc/sys/fs/binfmt_misc binfmt_misc defaults 0 0" to your -/etc/fstab so it auto mounts on boot. - -You may want to add the binary formats in one of your /etc/rc scripts during -boot-up. Read the manual of your init program to figure out how to do this -right. - -Think about the order of adding entries! Later added entries are matched first! - - -A few examples (assumed you are in /proc/sys/fs/binfmt_misc): - -- enable support for em86 (like binfmt_em86, for Alpha AXP only): - echo ':i386:M::\x7fELF\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x03:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfb\xff\xff:/bin/em86:' > register - echo ':i486:M::\x7fELF\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x06:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfb\xff\xff:/bin/em86:' > register - -- enable support for packed DOS applications (pre-configured dosemu hdimages): - echo ':DEXE:M::\x0eDEX::/usr/bin/dosexec:' > register - -- enable support for Windows executables using wine: - echo ':DOSWin:M::MZ::/usr/local/bin/wine:' > register - -For java support see Documentation/java.txt - - -You can enable/disable binfmt_misc or one binary type by echoing 0 (to disable) -or 1 (to enable) to /proc/sys/fs/binfmt_misc/status or /proc/.../the_name. -Catting the file tells you the current status of binfmt_misc/the entry. - -You can remove one entry or all entries by echoing -1 to /proc/.../the_name -or /proc/sys/fs/binfmt_misc/status. - - -HINTS: -====== - -If you want to pass special arguments to your interpreter, you can -write a wrapper script for it. See Documentation/java.txt for an -example. - -Your interpreter should NOT look in the PATH for the filename; the kernel -passes it the full filename (or the file descriptor) to use. Using $PATH can -cause unexpected behaviour and can be a security hazard. - - -Richard Günther <rguenth@tat.physik.uni-tuebingen.de> diff --git a/Documentation/blockdev/ramdisk.txt b/Documentation/blockdev/ramdisk.txt index fe2ef97..501e12e 100644 --- a/Documentation/blockdev/ramdisk.txt +++ b/Documentation/blockdev/ramdisk.txt @@ -14,7 +14,7 @@ Contents: The RAM disk driver is a way to use main system memory as a block device. It is required for initrd, an initial filesystem used if you need to load modules -in order to access the root filesystem (see Documentation/initrd.txt). It can +in order to access the root filesystem (see Documentation/admin-guide/initrd.rst). It can also be used for a temporary filesystem for crypto work, since the contents are erased on reboot. diff --git a/Documentation/braille-console.txt b/Documentation/braille-console.txt deleted file mode 100644 index d0d042c..0000000 --- a/Documentation/braille-console.txt +++ /dev/null @@ -1,34 +0,0 @@ - Linux Braille Console - -To get early boot messages on a braille device (before userspace screen -readers can start), you first need to compile the support for the usual serial -console (see serial-console.txt), and for braille device (in Device Drivers - -Accessibility). - -Then you need to specify a console=brl, option on the kernel command line, the -format is: - - console=brl,serial_options... - -where serial_options... are the same as described in serial-console.txt - -So for instance you can use console=brl,ttyS0 if the braille device is connected -to the first serial port, and console=brl,ttyS0,115200 to override the baud rate -to 115200, etc. - -By default, the braille device will just show the last kernel message (console -mode). To review previous messages, press the Insert key to switch to the VT -review mode. In review mode, the arrow keys permit to browse in the VT content, -page up/down keys go at the top/bottom of the screen, and the home key goes back -to the cursor, hence providing very basic screen reviewing facility. - -Sound feedback can be obtained by adding the braille_console.sound=1 kernel -parameter. - -For simplicity, only one braille console can be enabled, other uses of -console=brl,... will be discarded. Also note that it does not interfere with -the console selection mechanism described in serial-console.txt - -For now, only the VisioBraille device is supported. - -Samuel Thibault <samuel.thibault@ens-lyon.org> diff --git a/Documentation/cgroup-v1/00-INDEX b/Documentation/cgroup-v1/00-INDEX index 106885a..13e0c85 100644 --- a/Documentation/cgroup-v1/00-INDEX +++ b/Documentation/cgroup-v1/00-INDEX @@ -8,7 +8,7 @@ cpuacct.txt - CPU Accounting Controller; account CPU usage for groups of tasks. cpusets.txt - documents the cpusets feature; assign CPUs and Mem to a set of tasks. -devices.txt +admin-guide/devices.rst - Device Whitelist Controller; description, interface and security. freezer-subsystem.txt - checkpointing; rationale to not use signals, interface. diff --git a/Documentation/conf.py b/Documentation/conf.py index 4db1993..d9bad21 100644 --- a/Documentation/conf.py +++ b/Documentation/conf.py @@ -336,9 +336,11 @@ latex_elements = { # (source start file, target name, title, # author, documentclass [howto, manual, or own class]). latex_documents = [ + ('user/index', 'linux-user.tex', 'Linux Kernel User Documentation', + 'The kernel development community', 'manual'), ('kernel-documentation', 'kernel-documentation.tex', 'The Linux Kernel Documentation', 'The kernel development community', 'manual'), - ('development-process/index', 'development-process.tex', 'Linux Kernel Development Documentation', + ('process/index', 'development-process.tex', 'Linux Kernel Development Documentation', 'The kernel development community', 'manual'), ('gpu/index', 'gpu.tex', 'Linux GPU Driver Developer\'s Guide', 'The kernel development community', 'manual'), diff --git a/Documentation/development-process/index.rst b/Documentation/development-process/index.rst deleted file mode 100644 index c37475d..0000000 --- a/Documentation/development-process/index.rst +++ /dev/null @@ -1,9 +0,0 @@ -Linux Kernel Development Documentation -====================================== - -Contents: - -.. toctree:: - :maxdepth: 2 - - development-process diff --git a/Documentation/devicetree/bindings/rtc/maxim,ds3231.txt b/Documentation/devicetree/bindings/rtc/maxim,ds3231.txt index ddef330..1ad4c1c 100644 --- a/Documentation/devicetree/bindings/rtc/maxim,ds3231.txt +++ b/Documentation/devicetree/bindings/rtc/maxim,ds3231.txt @@ -1,7 +1,7 @@ * Maxim DS3231 Real Time Clock Required properties: -see: Documentation/devicetree/bindings/i2c/trivial-devices.txt +see: Documentation/devicetree/bindings/i2c/trivial-admin-guide/devices.rst Optional property: - #clock-cells: Should be 1. diff --git a/Documentation/devicetree/bindings/rtc/pcf8563.txt b/Documentation/devicetree/bindings/rtc/pcf8563.txt index 72f6d2c..086c998 100644 --- a/Documentation/devicetree/bindings/rtc/pcf8563.txt +++ b/Documentation/devicetree/bindings/rtc/pcf8563.txt @@ -3,7 +3,7 @@ Philips PCF8563/Epson RTC8564 Real Time Clock Required properties: -see: Documentation/devicetree/bindings/i2c/trivial-devices.txt +see: Documentation/devicetree/bindings/i2c/trivial-admin-guide/devices.rst Optional property: - #clock-cells: Should be 0. diff --git a/Documentation/devicetree/bindings/submitting-patches.txt b/Documentation/devicetree/bindings/submitting-patches.txt index 7d44eae..274058c 100644 --- a/Documentation/devicetree/bindings/submitting-patches.txt +++ b/Documentation/devicetree/bindings/submitting-patches.txt @@ -3,7 +3,7 @@ I. For patch submitters - 0) Normal patch submission rules from Documentation/SubmittingPatches + 0) Normal patch submission rules from Documentation/process/submitting-patches.rst applies. 1) The Documentation/ portion of the patch should be a separate patch. diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt deleted file mode 100644 index 9417871..0000000 --- a/Documentation/dynamic-debug-howto.txt +++ /dev/null @@ -1,340 +0,0 @@ - -Introduction -============ - -This document describes how to use the dynamic debug (dyndbg) feature. - -Dynamic debug is designed to allow you to dynamically enable/disable -kernel code to obtain additional kernel information. Currently, if -CONFIG_DYNAMIC_DEBUG is set, then all pr_debug()/dev_dbg() and -print_hex_dump_debug()/print_hex_dump_bytes() calls can be dynamically -enabled per-callsite. - -If CONFIG_DYNAMIC_DEBUG is not set, print_hex_dump_debug() is just -shortcut for print_hex_dump(KERN_DEBUG). - -For print_hex_dump_debug()/print_hex_dump_bytes(), format string is -its 'prefix_str' argument, if it is constant string; or "hexdump" -in case 'prefix_str' is build dynamically. - -Dynamic debug has even more useful features: - - * Simple query language allows turning on and off debugging - statements by matching any combination of 0 or 1 of: - - - source filename - - function name - - line number (including ranges of line numbers) - - module name - - format string - - * Provides a debugfs control file: <debugfs>/dynamic_debug/control - which can be read to display the complete list of known debug - statements, to help guide you - -Controlling dynamic debug Behaviour -=================================== - -The behaviour of pr_debug()/dev_dbg()s are controlled via writing to a -control file in the 'debugfs' filesystem. Thus, you must first mount -the debugfs filesystem, in order to make use of this feature. -Subsequently, we refer to the control file as: -<debugfs>/dynamic_debug/control. For example, if you want to enable -printing from source file 'svcsock.c', line 1603 you simply do: - -nullarbor:~ # echo 'file svcsock.c line 1603 +p' > - <debugfs>/dynamic_debug/control - -If you make a mistake with the syntax, the write will fail thus: - -nullarbor:~ # echo 'file svcsock.c wtf 1 +p' > - <debugfs>/dynamic_debug/control --bash: echo: write error: Invalid argument - -Viewing Dynamic Debug Behaviour -=========================== - -You can view the currently configured behaviour of all the debug -statements via: - -nullarbor:~ # cat <debugfs>/dynamic_debug/control -# filename:lineno [module]function flags format -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:323 [svcxprt_rdma]svc_rdma_cleanup =_ "SVCRDMA Module Removed, deregister RPC RDMA transport\012" -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:341 [svcxprt_rdma]svc_rdma_init =_ "\011max_inline : %d\012" -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:340 [svcxprt_rdma]svc_rdma_init =_ "\011sq_depth : %d\012" -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:338 [svcxprt_rdma]svc_rdma_init =_ "\011max_requests : %d\012" -... - - -You can also apply standard Unix text manipulation filters to this -data, e.g. - -nullarbor:~ # grep -i rdma <debugfs>/dynamic_debug/control | wc -l -62 - -nullarbor:~ # grep -i tcp <debugfs>/dynamic_debug/control | wc -l -42 - -The third column shows the currently enabled flags for each debug -statement callsite (see below for definitions of the flags). The -default value, with no flags enabled, is "=_". So you can view all -the debug statement callsites with any non-default flags: - -nullarbor:~ # awk '$3 != "=_"' <debugfs>/dynamic_debug/control -# filename:lineno [module]function flags format -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c:1603 [sunrpc]svc_send p "svc_process: st_sendto returned %d\012" - - -Command Language Reference -========================== - -At the lexical level, a command comprises a sequence of words separated -by spaces or tabs. So these are all equivalent: - -nullarbor:~ # echo -c 'file svcsock.c line 1603 +p' > - <debugfs>/dynamic_debug/control -nullarbor:~ # echo -c ' file svcsock.c line 1603 +p ' > - <debugfs>/dynamic_debug/control -nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > - <debugfs>/dynamic_debug/control - -Command submissions are bounded by a write() system call. -Multiple commands can be written together, separated by ';' or '\n'. - - ~# echo "func pnpacpi_get_resources +p; func pnp_assign_mem +p" \ - > <debugfs>/dynamic_debug/control - -If your query set is big, you can batch them too: - - ~# cat query-batch-file > <debugfs>/dynamic_debug/control - -A another way is to use wildcard. The match rule support '*' (matches -zero or more characters) and '?' (matches exactly one character).For -example, you can match all usb drivers: - - ~# echo "file drivers/usb/* +p" > <debugfs>/dynamic_debug/control - -At the syntactical level, a command comprises a sequence of match -specifications, followed by a flags change specification. - -command ::= match-spec* flags-spec - -The match-spec's are used to choose a subset of the known pr_debug() -callsites to which to apply the flags-spec. Think of them as a query -with implicit ANDs between each pair. Note that an empty list of -match-specs will select all debug statement callsites. - -A match specification comprises a keyword, which controls the -attribute of the callsite to be compared, and a value to compare -against. Possible keywords are: - -match-spec ::= 'func' string | - 'file' string | - 'module' string | - 'format' string | - 'line' line-range - -line-range ::= lineno | - '-'lineno | - lineno'-' | - lineno'-'lineno -// Note: line-range cannot contain space, e.g. -// "1-30" is valid range but "1 - 30" is not. - -lineno ::= unsigned-int - -The meanings of each keyword are: - -func - The given string is compared against the function name - of each callsite. Example: - - func svc_tcp_accept - -file - The given string is compared against either the full pathname, the - src-root relative pathname, or the basename of the source file of - each callsite. Examples: - - file svcsock.c - file kernel/freezer.c - file /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c - -module - The given string is compared against the module name - of each callsite. The module name is the string as - seen in "lsmod", i.e. without the directory or the .ko - suffix and with '-' changed to '_'. Examples: - - module sunrpc - module nfsd - -format - The given string is searched for in the dynamic debug format - string. Note that the string does not need to match the - entire format, only some part. Whitespace and other - special characters can be escaped using C octal character - escape \ooo notation, e.g. the space character is \040. - Alternatively, the string can be enclosed in double quote - characters (") or single quote characters ('). - Examples: - - format svcrdma: // many of the NFS/RDMA server pr_debugs - format readahead // some pr_debugs in the readahead cache - format nfsd:\040SETATTR // one way to match a format with whitespace - format "nfsd: SETATTR" // a neater way to match a format with whitespace - format 'nfsd: SETATTR' // yet another way to match a format with whitespace - -line - The given line number or range of line numbers is compared - against the line number of each pr_debug() callsite. A single - line number matches the callsite line number exactly. A - range of line numbers matches any callsite between the first - and last line number inclusive. An empty first number means - the first line in the file, an empty line number means the - last number in the file. Examples: - - line 1603 // exactly line 1603 - line 1600-1605 // the six lines from line 1600 to line 1605 - line -1605 // the 1605 lines from line 1 to line 1605 - line 1600- // all lines from line 1600 to the end of the file - -The flags specification comprises a change operation followed -by one or more flag characters. The change operation is one -of the characters: - - - remove the given flags - + add the given flags - = set the flags to the given flags - -The flags are: - - p enables the pr_debug() callsite. - f Include the function name in the printed message - l Include line number in the printed message - m Include module name in the printed message - t Include thread ID in messages not generated from interrupt context - _ No flags are set. (Or'd with others on input) - -For print_hex_dump_debug() and print_hex_dump_bytes(), only 'p' flag -have meaning, other flags ignored. - -For display, the flags are preceded by '=' -(mnemonic: what the flags are currently equal to). - -Note the regexp ^[-+=][flmpt_]+$ matches a flags specification. -To clear all flags at once, use "=_" or "-flmpt". - - -Debug messages during Boot Process -================================== - -To activate debug messages for core code and built-in modules during -the boot process, even before userspace and debugfs exists, use -dyndbg="QUERY", module.dyndbg="QUERY", or ddebug_query="QUERY" -(ddebug_query is obsoleted by dyndbg, and deprecated). QUERY follows -the syntax described above, but must not exceed 1023 characters. Your -bootloader may impose lower limits. - -These dyndbg params are processed just after the ddebug tables are -processed, as part of the arch_initcall. Thus you can enable debug -messages in all code run after this arch_initcall via this boot -parameter. - -On an x86 system for example ACPI enablement is a subsys_initcall and - dyndbg="file ec.c +p" -will show early Embedded Controller transactions during ACPI setup if -your machine (typically a laptop) has an Embedded Controller. -PCI (or other devices) initialization also is a hot candidate for using -this boot parameter for debugging purposes. - -If foo module is not built-in, foo.dyndbg will still be processed at -boot time, without effect, but will be reprocessed when module is -loaded later. dyndbg_query= and bare dyndbg= are only processed at -boot. - - -Debug Messages at Module Initialization Time -============================================ - -When "modprobe foo" is called, modprobe scans /proc/cmdline for -foo.params, strips "foo.", and passes them to the kernel along with -params given in modprobe args or /etc/modprob.d/*.conf files, -in the following order: - -1. # parameters given via /etc/modprobe.d/*.conf - options foo dyndbg=+pt - options foo dyndbg # defaults to +p - -2. # foo.dyndbg as given in boot args, "foo." is stripped and passed - foo.dyndbg=" func bar +p; func buz +mp" - -3. # args to modprobe - modprobe foo dyndbg==pmf # override previous settings - -These dyndbg queries are applied in order, with last having final say. -This allows boot args to override or modify those from /etc/modprobe.d -(sensible, since 1 is system wide, 2 is kernel or boot specific), and -modprobe args to override both. - -In the foo.dyndbg="QUERY" form, the query must exclude "module foo". -"foo" is extracted from the param-name, and applied to each query in -"QUERY", and only 1 match-spec of each type is allowed. - -The dyndbg option is a "fake" module parameter, which means: - -- modules do not need to define it explicitly -- every module gets it tacitly, whether they use pr_debug or not -- it doesn't appear in /sys/module/$module/parameters/ - To see it, grep the control file, or inspect /proc/cmdline. - -For CONFIG_DYNAMIC_DEBUG kernels, any settings given at boot-time (or -enabled by -DDEBUG flag during compilation) can be disabled later via -the sysfs interface if the debug messages are no longer needed: - - echo "module module_name -p" > <debugfs>/dynamic_debug/control - -Examples -======== - -// enable the message at line 1603 of file svcsock.c -nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > - <debugfs>/dynamic_debug/control - -// enable all the messages in file svcsock.c -nullarbor:~ # echo -n 'file svcsock.c +p' > - <debugfs>/dynamic_debug/control - -// enable all the messages in the NFS server module -nullarbor:~ # echo -n 'module nfsd +p' > - <debugfs>/dynamic_debug/control - -// enable all 12 messages in the function svc_process() -nullarbor:~ # echo -n 'func svc_process +p' > - <debugfs>/dynamic_debug/control - -// disable all 12 messages in the function svc_process() -nullarbor:~ # echo -n 'func svc_process -p' > - <debugfs>/dynamic_debug/control - -// enable messages for NFS calls READ, READLINK, READDIR and READDIR+. -nullarbor:~ # echo -n 'format "nfsd: READ" +p' > - <debugfs>/dynamic_debug/control - -// enable messages in files of which the paths include string "usb" -nullarbor:~ # echo -n '*usb* +p' > <debugfs>/dynamic_debug/control - -// enable all messages -nullarbor:~ # echo -n '+p' > <debugfs>/dynamic_debug/control - -// add module, function to all enabled messages -nullarbor:~ # echo -n '+mf' > <debugfs>/dynamic_debug/control - -// boot-args example, with newlines and comments for readability -Kernel command line: ... - // see whats going on in dyndbg=value processing - dynamic_debug.verbose=1 - // enable pr_debugs in 2 builtins, #cmt is stripped - dyndbg="module params +p #cmt ; module sys +p" - // enable pr_debugs in 2 functions in a module loaded later - pc87360.dyndbg="func pc87360_init_device +p; func pc87360_find +p" diff --git a/Documentation/filesystems/locks.txt b/Documentation/filesystems/locks.txt index 2cf8108..5368690 100644 --- a/Documentation/filesystems/locks.txt +++ b/Documentation/filesystems/locks.txt @@ -19,7 +19,7 @@ forever. This should not cause problems for anybody, since everybody using a 2.1.x kernel should have updated their C library to a suitable version -anyway (see the file "Documentation/Changes".) +anyway (see the file "Documentation/process/changes.rst".) 1.2 Allow Mixed Locks Again --------------------------- diff --git a/Documentation/filesystems/nfs/nfsroot.txt b/Documentation/filesystems/nfs/nfsroot.txt index 0b2883b..5efae00 100644 --- a/Documentation/filesystems/nfs/nfsroot.txt +++ b/Documentation/filesystems/nfs/nfsroot.txt @@ -11,7 +11,7 @@ Updated 2006 by Horms <horms@verge.net.au> In order to use a diskless system, such as an X-terminal or printer server for example, it is necessary for the root filesystem to be present on a non-disk device. This may be an initramfs (see Documentation/filesystems/ -ramfs-rootfs-initramfs.txt), a ramdisk (see Documentation/initrd.txt) or a +ramfs-rootfs-initramfs.txt), a ramdisk (see Documentation/admin-guide/initrd.rst) or a filesystem mounted via NFS. The following text describes on how to use NFS for the root filesystem. For the rest of this text 'client' means the diskless system, and 'server' means the NFS server. @@ -284,7 +284,7 @@ They depend on various facilities being available: "kernel <relative-path-below /tftpboot>". The nfsroot parameters are passed to the kernel by adding them to the "append" line. It is common to use serial console in conjunction with pxeliunx, - see Documentation/serial-console.txt for more information. + see Documentation/admin-guide/serial-console.rst for more information. For more information on isolinux, including how to create bootdisks for prebuilt kernels, see http://syslinux.zytor.com/ diff --git a/Documentation/frv/booting.txt b/Documentation/frv/booting.txt index 9bdf4b4..cd9dc1d 100644 --- a/Documentation/frv/booting.txt +++ b/Documentation/frv/booting.txt @@ -119,7 +119,7 @@ separated by spaces: 253:0 Device with major 253 and minor 0 Authoritative information can be found in - "Documentation/kernel-parameters.txt". + "Documentation/admin-guide/kernel-parameters.rst". (*) rw diff --git a/Documentation/hwmon/submitting-patches b/Documentation/hwmon/submitting-patches index 57f6030..f88221b 100644 --- a/Documentation/hwmon/submitting-patches +++ b/Documentation/hwmon/submitting-patches @@ -10,10 +10,10 @@ increase the chances of your change being accepted. ---------- * It should be unnecessary to mention, but please read and follow - Documentation/SubmitChecklist - Documentation/SubmittingDrivers - Documentation/SubmittingPatches - Documentation/CodingStyle + Documentation/process/submit-checklist.rst + Documentation/process/submitting-drivers.rst + Documentation/process/submitting-patches.rst + Documentation/process/coding-style.rst * Please run your patch through 'checkpatch --strict'. There should be no errors, no warnings, and few if any check messages. If there are any diff --git a/Documentation/index.rst b/Documentation/index.rst index c53d089..f6a3d47 100644 --- a/Documentation/index.rst +++ b/Documentation/index.rst @@ -11,8 +11,9 @@ Contents: .. toctree:: :maxdepth: 2 + admin-guide/index kernel-documentation - development-process/index + process/index dev-tools/tools driver-api/index media/index diff --git a/Documentation/isdn/README b/Documentation/isdn/README index cfb1884..32d4e80 100644 --- a/Documentation/isdn/README +++ b/Documentation/isdn/README @@ -332,7 +332,7 @@ README for the ISDN-subsystem 4. Device-inodes The major and minor numbers and their names are described in - Documentation/devices.txt. The major numbers are: + Documentation/admin-guide/devices.rst. The major numbers are: 43 for the ISDN-tty's. 44 for the ISDN-callout-tty's. diff --git a/Documentation/ja_JP/HOWTO b/Documentation/ja_JP/HOWTO index 581c14b..b03fc80 100644 --- a/Documentation/ja_JP/HOWTO +++ b/Documentation/ja_JP/HOWTO @@ -127,15 +127,15 @@ linux-api@ver.kernel.org に送ることを勧めます。 小限のレベルで必要な数々のソフトウェアパッケージの一覧を示してい ます。 - Documentation/CodingStyle + Documentation/process/coding-style.rst これは Linux カーネルのコーディングスタイルと背景にある理由を記述 しています。全ての新しいコードはこのドキュメントにあるガイドライン に従っていることを期待されています。大部分のメンテナはこれらのルー ルに従っているものだけを受け付け、多くの人は正しいスタイルのコード だけをレビューします。 - Documentation/SubmittingPatches - Documentation/SubmittingDrivers + Documentation/process/submitting-patches.rst + Documentation/process/submitting-drivers.rst これらのファイルには、どうやってうまくパッチを作って投稿するかに ついて非常に詳しく書かれており、以下を含みます(これだけに限らない けれども) @@ -153,7 +153,7 @@ linux-api@ver.kernel.org に送ることを勧めます。 "Linux kernel patch submission format" http://linux.yyz.us/patch-format.html - Documentation/stable_api_nonsense.txt + Documentation/process/stable-api-nonsense.rst このファイルはカーネルの中に不変のAPIを持たないことにした意識的な 決断の背景にある理由について書かれています。以下のようなことを含 んでいます- @@ -164,29 +164,29 @@ linux-api@ver.kernel.org に送ることを勧めます。 このドキュメントは Linux 開発の思想を理解するのに非常に重要です。 そして、他のOSでの開発者が Linux に移る時にとても重要です。 - Documentation/SecurityBugs + Documentation/admin-guide/security-bugs.rst もし Linux カーネルでセキュリティ問題を発見したように思ったら、こ のドキュメントのステップに従ってカーネル開発者に連絡し、問題解決を 支援してください。 - Documentation/ManagementStyle + Documentation/process/management-style.rst このドキュメントは Linux カーネルのメンテナ達がどう行動するか、 彼らの手法の背景にある共有されている精神について記述しています。こ れはカーネル開発の初心者なら（もしくは、単に興味があるだけの人でも） 重要です。なぜならこのドキュメントは、カーネルメンテナ達の独特な 行動についての多くの誤解や混乱を解消するからです。 - Documentation/stable_kernel_rules.txt + Documentation/process/stable-kernel-rules.rst このファイルはどのように stable カーネルのリリースが行われるかのルー ルが記述されています。そしてこれらのリリースの中のどこかで変更を取 り入れてもらいたい場合に何をすれば良いかが示されています。 - Documentation/kernel-docs.txt + Documentation/process/kernel-docs.rst カーネル開発に付随する外部ドキュメントのリストです。もしあなたが 探しているものがカーネル内のドキュメントでみつからなかった場合、 このリストをあたってみてください。 - Documentation/applying-patches.txt + Documentation/process/applying-patches.rst パッチとはなにか、パッチをどうやって様々なカーネルの開発ブランチに 適用するのかについて正確に記述した良い入門書です。 @@ -314,7 +314,7 @@ Andrew Morton が Linux-kernel メーリングリストにカーネルリリー た問題がなければもう少し長くなることもあります。セキュリティ関連の問題 の場合はこれに対してだいたいの場合、すぐにリリースがされます。 -カーネルツリーに入っている、Documentation/stable_kernel_rules.txt ファ +カーネルツリーに入っている、Documentation/process/stable-kernel-rules.rst ファ イルにはどのような種類の変更が -stable ツリーに受け入れ可能か、またリ リースプロセスがどう動くかが記述されています。 @@ -372,7 +372,7 @@ bugzilla.kernel.org は Linux カーネル開発者がカーネルのバグを 場所です。ユーザは見つけたバグの全てをこのツールで報告すべきです。 どう kernel bugzilla を使うかの詳細は、以下を参照してください- http://bugzilla.kernel.org/page.cgi?id=faq.html -メインカーネルソースディレクトリにあるファイル REPORTING-BUGS はカーネ +メインカーネルソースディレクトリにあるファイル admin-guide/reporting-bugs.rst はカーネ ルバグらしいものについてどうレポートするかの良いテンプレートであり、問 題の追跡を助けるためにカーネル開発者にとってどんな情報が必要なのかの詳 細が書かれています。 @@ -438,7 +438,7 @@ MAINTAINERS ファイルにリストがありますので参照してくださ メールの先頭でなく、各引用行の間にあなたの言いたいことを追加するべきで す。 -もしパッチをメールに付ける場合は、Documentation/SubmittingPatches に提 +もしパッチをメールに付ける場合は、Documentation/process/submitting-patches.rst に提 示されているように、それは プレーンな可読テキストにすることを忘れない ようにしましょう。カーネル開発者は 添付や圧縮したパッチを扱いたがりま せん- diff --git a/Documentation/ja_JP/SubmitChecklist b/Documentation/ja_JP/SubmitChecklist index cb5507b..60c7c35 100644 --- a/Documentation/ja_JP/SubmitChecklist +++ b/Documentation/ja_JP/SubmitChecklist @@ -1,5 +1,5 @@ NOTE: -This is a version of Documentation/SubmitChecklist into Japanese. +This is a version of Documentation/process/submit-checklist.rst into Japanese. This document is maintained by Takenori Nagano <t-nagano@ah.jp.nec.com> and the JF Project team <http://www.linux.or.jp/JF/>. If you find any difference between this document and the original file @@ -14,7 +14,7 @@ to update the original English file first. Last Updated: 2008/07/14 ================================== これは、 -linux-2.6.26/Documentation/SubmitChecklist の和訳です。 +linux-2.6.26/Documentation/process/submit-checklist.rst の和訳です。 翻訳団体： JF プロジェクト < http://www.linux.or.jp/JF/ > 翻訳日： 2008/07/14 @@ -27,7 +27,7 @@ Linux カーネルパッチ投稿者向けチェックリスト ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 本書では、パッチをより素早く取り込んでもらいたい開発者が実践すべき基本的な事柄 -をいくつか紹介します。ここにある全ての事柄は、Documentation/SubmittingPatches +をいくつか紹介します。ここにある全ての事柄は、Documentation/process/submitting-patches.rst などのLinuxカーネルパッチ投稿に際しての心得を補足するものです。 1: 妥当なCONFIGオプションや変更されたCONFIGオプション、つまり =y, =m, =n @@ -84,7 +84,7 @@ Linux カーネルパッチ投稿者向けチェックリスト 必ずドキュメントを追加してください。 17: 新しいブートパラメータを追加した場合には、 - 必ずDocumentation/kernel-parameters.txt に説明を追加してください。 + 必ずDocumentation/admin-guide/kernel-parameters.rst に説明を追加してください。 18: 新しくmoduleにパラメータを追加した場合には、MODULE_PARM_DESC()を 利用して必ずその説明を記述してください。 diff --git a/Documentation/ja_JP/SubmittingPatches b/Documentation/ja_JP/SubmittingPatches index 5d6ae63..0213965 100644 --- a/Documentation/ja_JP/SubmittingPatches +++ b/Documentation/ja_JP/SubmittingPatches @@ -1,5 +1,5 @@ NOTE: -This is a version of Documentation/SubmittingPatches into Japanese. +This is a version of Documentation/process/submitting-patches.rst into Japanese. This document is maintained by Keiichi KII <k-keiichi@bx.jp.nec.com> and the JF Project team <http://www.linux.or.jp/JF/>. If you find any difference between this document and the original file @@ -15,7 +15,7 @@ Last Updated: 2011/06/09 ================================== これは、 -linux-2.6.39/Documentation/SubmittingPatches の和訳 +linux-2.6.39/Documentation/process/submitting-patches.rst の和訳 です。 翻訳団体： JF プロジェクト < http://www.linux.or.jp/JF/ > 翻訳日： 2011/06/09 @@ -34,9 +34,9 @@ Linux カーネルに変更を加えたいと思っている個人又は会社 おじけづかせることもあります。この文章はあなたの変更を大いに受け入れ てもらえやすくする提案を集めたものです。 -コードを投稿する前に、Documentation/SubmitChecklist の項目リストに目 +コードを投稿する前に、Documentation/process/submit-checklist.rst の項目リストに目 を通してチェックしてください。もしあなたがドライバーを投稿しようとし -ているなら、Documentation/SubmittingDrivers にも目を通してください。 +ているなら、Documentation/process/submitting-drivers.rst にも目を通してください。 -------------------------------------------- セクション1 パッチの作り方と送り方 @@ -148,7 +148,7 @@ http://savannah.nongnu.org/projects/quilt 4) パッチのスタイルチェック あなたのパッチが基本的な( Linux カーネルの)コーディングスタイルに違反し -ていないかをチェックして下さい。その詳細を Documentation/CodingStyle で +ていないかをチェックして下さい。その詳細を Documentation/process/coding-style.rst で 見つけることができます。コーディングスタイルの違反はレビューする人の 時間を無駄にするだけなので、恐らくあなたのパッチは読まれることすらなく 拒否されるでしょう。 @@ -246,7 +246,7 @@ MIME 形式の添付ファイルは Linus に手間を取らせることにな あれば、誰かが MIME 形式のパッチを再送するよう求めるかもしれません。 余計な変更を加えずにあなたのパッチを送信するための電子メールクライアントの設定 -のヒントについては Documentation/email-clients.txt を参照してください。 +のヒントについては Documentation/process/email-clients.rst を参照してください。 8) 電子メールのサイズ @@ -609,7 +609,7 @@ diffstat の結果を生成するために「 git diff -M --stat --summary 」 し例外を適用するには、本当に妥当な理由が不可欠です。あなたは恐らくこの セクションを Linus のコンピュータ・サイエンス101と呼ぶでしょう。 -1) Documentation/CodingStyleを参照 +1) Documentation/process/coding-style.rstを参照 言うまでもなく、あなたのコードがこのコーディングスタイルからあまりに も逸脱していると、レビューやコメントなしに受け取ってもらえないかもし @@ -704,8 +704,8 @@ Greg Kroah-Hartman, "How to piss off a kernel subsystem maintainer". NO!!!! No more huge patch bombs to linux-kernel@vger.kernel.org people! <https://lkml.org/lkml/2005/7/11/336> -Kernel Documentation/CodingStyle: - <http://users.sosdg.org/~qiyong/lxr/source/Documentation/CodingStyle> +Kernel Documentation/process/coding-style.rst: + <http://users.sosdg.org/~qiyong/lxr/source/Documentation/process/coding-style.rst> Linus Torvalds's mail on the canonical patch format: <http://lkml.org/lkml/2005/4/7/183> diff --git a/Documentation/ja_JP/stable_api_nonsense.txt b/Documentation/ja_JP/stable_api_nonsense.txt index 7653b5c..a3b40a4 100644 --- a/Documentation/ja_JP/stable_api_nonsense.txt +++ b/Documentation/ja_JP/stable_api_nonsense.txt @@ -1,5 +1,5 @@ NOTE: -This is a version of Documentation/stable_api_nonsense.txt into Japanese. +This is a version of Documentation/process/stable-api-nonsense.rst into Japanese. This document is maintained by IKEDA, Munehiro <m-ikeda@ds.jp.nec.com> and the JF Project team <http://www.linux.or.jp/JF/>. If you find any difference between this document and the original file @@ -14,7 +14,7 @@ to update the original English file first. Last Updated: 2007/07/18 ================================== これは、 -linux-2.6.22-rc4/Documentation/stable_api_nonsense.txt の和訳 +linux-2.6.22-rc4/Documentation/process/stable-api-nonsense.rst の和訳 です。 翻訳団体： JF プロジェクト < http://www.linux.or.jp/JF/ > 翻訳日 ： 2007/06/11 diff --git a/Documentation/ja_JP/stable_kernel_rules.txt b/Documentation/ja_JP/stable_kernel_rules.txt index 9dbda9b..f9249ae 100644 --- a/Documentation/ja_JP/stable_kernel_rules.txt +++ b/Documentation/ja_JP/stable_kernel_rules.txt @@ -1,5 +1,5 @@ NOTE: -This is Japanese translated version of "Documentation/stable_kernel_rules.txt". +This is Japanese translated version of "Documentation/process/stable-kernel-rules.rst". This one is maintained by Tsugikazu Shibata <tshibata@ab.jp.nec.com> and JF Project team <www.linux.or.jp/JF>. If you find difference with original file or problem in translation, @@ -12,7 +12,7 @@ file at first. ================================== これは、 -linux-2.6.29/Documentation/stable_kernel_rules.txt +linux-2.6.29/Documentation/process/stable-kernel-rules.rst の和訳です。 翻訳団体： JF プロジェクト < http://www.linux.or.jp/JF/ > @@ -43,7 +43,7 @@ linux-2.6.29/Documentation/stable_kernel_rules.txt "理論的には競合状態になる"ようなものは不可。 - いかなる些細な修正も含めることはできない。(スペルの修正、空白のクリー ンアップなど) - - Documentation/SubmittingPatches の規則に従ったものでなければならない。 + - Documentation/process/submitting-patches.rst の規則に従ったものでなければならない。 - パッチ自体か同等の修正が Linus のツリーに既に存在しなければならない。 Linus のツリーでのコミットID を -stable へのパッチ投稿の際に引用す ること。 diff --git a/Documentation/kernel-per-CPU-kthreads.txt b/Documentation/kernel-per-CPU-kthreads.txt index bbc3a8b..df31e30 100644 --- a/Documentation/kernel-per-CPU-kthreads.txt +++ b/Documentation/kernel-per-CPU-kthreads.txt @@ -264,7 +264,7 @@ To reduce its OS jitter, do at least one of the following: kthreads from being created in the first place. 2. Boot with "nosoftlockup=0", which will also prevent these kthreads from being created. Other related watchdog and softlockup boot - parameters may be found in Documentation/kernel-parameters.txt + parameters may be found in Documentation/admin-guide/kernel-parameters.rst and Documentation/watchdog/watchdog-parameters.txt. 3. Echo a zero to /proc/sys/kernel/watchdog to disable the watchdog timer. diff --git a/Documentation/ko_KR/HOWTO b/Documentation/ko_KR/HOWTO index 9a3e659..0252527 100644 --- a/Documentation/ko_KR/HOWTO +++ b/Documentation/ko_KR/HOWTO @@ -1,5 +1,5 @@ NOTE: -This is a version of Documentation/HOWTO translated into korean +This is a version of Documentation/process/howto.rst translated into korean This document is maintained by Minchan Kim <minchan@kernel.org> If you find any difference between this document and the original file or a problem with the translation, please contact the maintainer of this file. @@ -11,7 +11,7 @@ try to update the original English file first. ================================== 이 문서는 -Documentation/HOWTO +Documentation/process/howto.rst 의 한글 번역입니다. 역자： 김민찬 <minchan@kernel.org> @@ -98,18 +98,18 @@ mtk.manpages@gmail.com의 메인테이너에게 보낼 것을 권장한다. 빌드하기 위해 필요한 것을 설명한다. 커널에 입문하는 사람들은 여기서 시작해야 한다. - Documentation/Changes + Documentation/process/changes.rst 이 파일은 커널을 성공적으로 빌드하고 실행시키기 위해 필요한 다양한 소프트웨어 패키지들의 최소 버젼을 나열한다. - Documentation/CodingStyle + Documentation/process/coding-style.rst 이 문서는 리눅스 커널 코딩 스타일과 그렇게 한 몇몇 이유를 설명한다. 모든 새로운 코드는 이 문서에 가이드라인들을 따라야 한다. 대부분의 메인테이너들은 이 규칙을 따르는 패치들만을 받아들일 것이고 많은 사람들이 그 패치가 올바른 스타일일 경우만 코드를 검토할 것이다. - Documentation/SubmittingPatches - Documentation/SubmittingDrivers + Documentation/process/submitting-patches.rst + Documentation/process/submitting-drivers.rst 이 파일들은 성공적으로 패치를 만들고 보내는 법을 다음의 내용들로 굉장히 상세히 설명하고 있다(그러나 다음으로 한정되진 않는다). - Email 내용들 @@ -126,7 +126,7 @@ mtk.manpages@gmail.com의 메인테이너에게 보낼 것을 권장한다. "Linux kernel patch submission format" http://linux.yyz.us/patch-format.html - Documentation/stable_api_nonsense.txt + Documentation/process/stable-api-nonsense.rst 이 문서는 의도적으로 커널이 불변하는 API를 갖지 않도록 결정한 이유를 설명하며 다음과 같은 것들을 포함한다. - 서브시스템 shim-layer(호환성을 위해?) @@ -136,12 +136,12 @@ mtk.manpages@gmail.com의 메인테이너에게 보낼 것을 권장한다. 리눅스로 전향하는 사람들에게는 매우 중요하다. - Documentation/SecurityBugs + Documentation/admin-guide/security-bugs.rst 여러분들이 리눅스 커널의 보안 문제를 발견했다고 생각한다면 이 문서에 나온 단계에 따라서 커널 개발자들에게 알리고 그 문제를 해결할 수 있도록 도와 달라. - Documentation/ManagementStyle + Documentation/process/management-style.rst 이 문서는 리눅스 커널 메인테이너들이 그들의 방법론에 녹아 있는 정신을 어떻게 공유하고 운영하는지를 설명한다. 이것은 커널 개발에 입문하는 모든 사람들(또는 커널 개발에 작은 호기심이라도 있는 사람들)이 @@ -149,17 +149,17 @@ mtk.manpages@gmail.com의 메인테이너에게 보낼 것을 권장한다. 독특한 행동에 관하여 흔히 있는 오해들과 혼란들을 해소하고 있기 때문이다. - Documentation/stable_kernel_rules.txt + Documentation/process/stable-kernel-rules.rst 이 문서는 안정적인 커널 배포가 이루어지는 규칙을 설명하고 있으며 여러분들이 이러한 배포들 중 하나에 변경을 하길 원한다면 무엇을 해야 하는지를 설명한다. - Documentation/kernel-docs.txt + Documentation/process/kernel-docs.rst 커널 개발에 관계된 외부 문서의 리스트이다. 커널 내의 포함된 문서들 중에 여러분이 찾고 싶은 문서를 발견하지 못할 경우 이 리스트를 살펴보라. - Documentation/applying-patches.txt + Documentation/process/applying-patches.rst 패치가 무엇이며 그것을 커널의 다른 개발 브랜치들에 어떻게 적용하는지에 관하여 자세히 설명하고 있는 좋은 입문서이다. @@ -276,7 +276,7 @@ Andrew Morton의 글이 있다. 4.x.y는 "stable" 팀<stable@vger.kernel.org>에 의해 관리되며 거의 매번 격주로 배포된다. -커널 트리 문서들 내에 Documentation/stable_kernel_rules.txt 파일은 어떤 +커널 트리 문서들 내에 Documentation/process/stable-kernel-rules.rst 파일은 어떤 종류의 변경들이 -stable 트리로 들어왔는지와 배포 프로세스가 어떻게 진행되는지를 설명한다. @@ -328,7 +328,7 @@ bugzilla.kernel.org는 리눅스 커널 개발자들이 커널의 버그를 추 kernel bugzilla를 사용하는 자세한 방법은 다음을 참조하라. http://test.kernel.org/bugzilla/faq.html -메인 커널 소스 디렉토리에 있는 REPORTING-BUGS 파일은 커널 버그라고 생각되는 +메인 커널 소스 디렉토리에 있는 admin-guide/reporting-bugs.rst 파일은 커널 버그라고 생각되는 것을 보고하는 방법에 관한 좋은 템플릿이며 문제를 추적하기 위해서 커널 개발자들이 필요로 하는 정보가 무엇들인지를 상세히 설명하고 있다. @@ -391,7 +391,7 @@ bugme-janitor 메일링 리스트(bugzilla에 모든 변화들이 여기서 메 "John 커널해커는 작성했다...."를 유지하며 여러분들의 의견을 그 메일의 윗부분에 작성하지 말고 각 인용한 단락들 사이에 넣어라. -여러분들이 패치들을 메일에 넣는다면 그것들은 Documentation/SubmittingPatches에 +여러분들이 패치들을 메일에 넣는다면 그것들은 Documentation/process/submitting-patches.rst에 나와있는데로 명백히(plain) 읽을 수 있는 텍스트여야 한다. 커널 개발자들은 첨부파일이나 압축된 패치들을 원하지 않는다. 그들은 여러분들의 패치의 각 라인 단위로 코멘트를 하길 원하며 압축하거나 첨부하지 않고 보내는 것이 diff --git a/Documentation/ko_KR/stable_api_nonsense.txt b/Documentation/ko_KR/stable_api_nonsense.txt index 3ba10b1..4d93af1 100644 --- a/Documentation/ko_KR/stable_api_nonsense.txt +++ b/Documentation/ko_KR/stable_api_nonsense.txt @@ -1,5 +1,5 @@ NOTE: -This is a version of Documentation/stable_api_nonsense.txt translated +This is a version of Documentation/process/stable-api-nonsense.rst translated into korean This document is maintained by Minchan Kim <minchan@kernel.org> If you find any difference between this document and the original file or @@ -12,7 +12,7 @@ try to update the original English file first. ================================== 이 문서는 -Documentation/stable_api_nonsense.txt +Documentation/process/stable-api-nonsense.rst 의 한글 번역입니다. 역자： 김민찬 <minchan@kernel.org> diff --git a/Documentation/lockup-watchdogs.txt b/Documentation/lockup-watchdogs.txt index 4a6e33e..c8b8378 100644 --- a/Documentation/lockup-watchdogs.txt +++ b/Documentation/lockup-watchdogs.txt @@ -11,7 +11,7 @@ details), without giving other tasks a chance to run. The current stack trace is displayed upon detection and, by default, the system will stay locked up. Alternatively, the kernel can be configured to panic; a sysctl, "kernel.softlockup_panic", a kernel parameter, -"softlockup_panic" (see "Documentation/kernel-parameters.txt" for +"softlockup_panic" (see "Documentation/admin-guide/kernel-parameters.rst" for details), and a compile option, "BOOTPARAM_SOFTLOCKUP_PANIC", are provided for this. @@ -23,7 +23,7 @@ upon detection and the system will stay locked up unless the default behavior is changed, which can be done through a sysctl, 'hardlockup_panic', a compile time knob, "BOOTPARAM_HARDLOCKUP_PANIC", and a kernel parameter, "nmi_watchdog" -(see "Documentation/kernel-parameters.txt" for details). +(see "Documentation/admin-guide/kernel-parameters.rst" for details). The panic option can be used in combination with panic_timeout (this timeout is set through the confusingly named "kernel.panic" sysctl), diff --git a/Documentation/m68k/kernel-options.txt b/Documentation/m68k/kernel-options.txt index eaf32a1..79d2124 100644 --- a/Documentation/m68k/kernel-options.txt +++ b/Documentation/m68k/kernel-options.txt @@ -139,7 +139,7 @@ follows: PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF/PARTNROFF=-2 Authoritative information can be found in -"Documentation/kernel-parameters.txt". +"Documentation/admin-guide/kernel-parameters.rst". 2.2) ro, rw diff --git a/Documentation/magic-number.txt b/Documentation/magic-number.txt deleted file mode 100644 index 28befed..0000000 --- a/Documentation/magic-number.txt +++ /dev/null @@ -1,158 +0,0 @@ -This file is a registry of magic numbers which are in use. When you -add a magic number to a structure, you should also add it to this -file, since it is best if the magic numbers used by various structures -are unique. - -It is a *very* good idea to protect kernel data structures with magic -numbers. This allows you to check at run time whether (a) a structure -has been clobbered, or (b) you've passed the wrong structure to a -routine. This last is especially useful --- particularly when you are -passing pointers to structures via a void * pointer. The tty code, -for example, does this frequently to pass driver-specific and line -discipline-specific structures back and forth. - -The way to use magic numbers is to declare then at the beginning of -the structure, like so: - -struct tty_ldisc { - int magic; - ... -}; - -Please follow this discipline when you are adding future enhancements -to the kernel! It has saved me countless hours of debugging, -especially in the screwy cases where an array has been overrun and -structures following the array have been overwritten. Using this -discipline, these cases get detected quickly and safely. - - Theodore Ts'o - 31 Mar 94 - -The magic table is current to Linux 2.1.55. - - Michael Chastain - <mailto:mec@shout.net> - 22 Sep 1997 - -Now it should be up to date with Linux 2.1.112. Because -we are in feature freeze time it is very unlikely that -something will change before 2.2.x. The entries are -sorted by number field. - - Krzysztof G. Baranowski - <mailto: kgb@knm.org.pl> - 29 Jul 1998 - -Updated the magic table to Linux 2.5.45. Right over the feature freeze, -but it is possible that some new magic numbers will sneak into the -kernel before 2.6.x yet. - - Petr Baudis - <pasky@ucw.cz> - 03 Nov 2002 - -Updated the magic table to Linux 2.5.74. - - Fabian Frederick - <ffrederick@users.sourceforge.net> - 09 Jul 2003 - - -Magic Name Number Structure File -=========================================================================== -PG_MAGIC 'P' pg_{read,write}_hdr include/linux/pg.h -CMAGIC 0x0111 user include/linux/a.out.h -MKISS_DRIVER_MAGIC 0x04bf mkiss_channel drivers/net/mkiss.h -HDLC_MAGIC 0x239e n_hdlc drivers/char/n_hdlc.c -APM_BIOS_MAGIC 0x4101 apm_user arch/x86/kernel/apm_32.c -CYCLADES_MAGIC 0x4359 cyclades_port include/linux/cyclades.h -DB_MAGIC 0x4442 fc_info drivers/net/iph5526_novram.c -DL_MAGIC 0x444d fc_info drivers/net/iph5526_novram.c -FASYNC_MAGIC 0x4601 fasync_struct include/linux/fs.h -FF_MAGIC 0x4646 fc_info drivers/net/iph5526_novram.c -ISICOM_MAGIC 0x4d54 isi_port include/linux/isicom.h -PTY_MAGIC 0x5001 drivers/char/pty.c -PPP_MAGIC 0x5002 ppp include/linux/if_pppvar.h -SERIAL_MAGIC 0x5301 async_struct include/linux/serial.h -SSTATE_MAGIC 0x5302 serial_state include/linux/serial.h -SLIP_MAGIC 0x5302 slip drivers/net/slip.h -STRIP_MAGIC 0x5303 strip drivers/net/strip.c -X25_ASY_MAGIC 0x5303 x25_asy drivers/net/x25_asy.h -SIXPACK_MAGIC 0x5304 sixpack drivers/net/hamradio/6pack.h -AX25_MAGIC 0x5316 ax_disp drivers/net/mkiss.h -TTY_MAGIC 0x5401 tty_struct include/linux/tty.h -MGSL_MAGIC 0x5401 mgsl_info drivers/char/synclink.c -TTY_DRIVER_MAGIC 0x5402 tty_driver include/linux/tty_driver.h -MGSLPC_MAGIC 0x5402 mgslpc_info drivers/char/pcmcia/synclink_cs.c -TTY_LDISC_MAGIC 0x5403 tty_ldisc include/linux/tty_ldisc.h -USB_SERIAL_MAGIC 0x6702 usb_serial drivers/usb/serial/usb-serial.h -FULL_DUPLEX_MAGIC 0x6969 drivers/net/ethernet/dec/tulip/de2104x.c -USB_BLUETOOTH_MAGIC 0x6d02 usb_bluetooth drivers/usb/class/bluetty.c -RFCOMM_TTY_MAGIC 0x6d02 net/bluetooth/rfcomm/tty.c -USB_SERIAL_PORT_MAGIC 0x7301 usb_serial_port drivers/usb/serial/usb-serial.h -CG_MAGIC 0x00090255 ufs_cylinder_group include/linux/ufs_fs.h -RPORT_MAGIC 0x00525001 r_port drivers/char/rocket_int.h -LSEMAGIC 0x05091998 lse drivers/fc4/fc.c -GDTIOCTL_MAGIC 0x06030f07 gdth_iowr_str drivers/scsi/gdth_ioctl.h -RIEBL_MAGIC 0x09051990 drivers/net/atarilance.c -NBD_REQUEST_MAGIC 0x12560953 nbd_request include/linux/nbd.h -RED_MAGIC2 0x170fc2a5 (any) mm/slab.c -BAYCOM_MAGIC 0x19730510 baycom_state drivers/net/baycom_epp.c -ISDN_X25IFACE_MAGIC 0x1e75a2b9 isdn_x25iface_proto_data - drivers/isdn/isdn_x25iface.h -ECP_MAGIC 0x21504345 cdkecpsig include/linux/cdk.h -LSOMAGIC 0x27091997 lso drivers/fc4/fc.c -LSMAGIC 0x2a3b4d2a ls drivers/fc4/fc.c -WANPIPE_MAGIC 0x414C4453 sdla_{dump,exec} include/linux/wanpipe.h -CS_CARD_MAGIC 0x43525553 cs_card sound/oss/cs46xx.c -LABELCL_MAGIC 0x4857434c labelcl_info_s include/asm/ia64/sn/labelcl.h -ISDN_ASYNC_MAGIC 0x49344C01 modem_info include/linux/isdn.h -CTC_ASYNC_MAGIC 0x49344C01 ctc_tty_info drivers/s390/net/ctctty.c -ISDN_NET_MAGIC 0x49344C02 isdn_net_local_s drivers/isdn/i4l/isdn_net_lib.h -SAVEKMSG_MAGIC2 0x4B4D5347 savekmsg arch/*/amiga/config.c -CS_STATE_MAGIC 0x4c4f4749 cs_state sound/oss/cs46xx.c -SLAB_C_MAGIC 0x4f17a36d kmem_cache mm/slab.c -COW_MAGIC 0x4f4f4f4d cow_header_v1 arch/um/drivers/ubd_user.c -I810_CARD_MAGIC 0x5072696E i810_card sound/oss/i810_audio.c -TRIDENT_CARD_MAGIC 0x5072696E trident_card sound/oss/trident.c -ROUTER_MAGIC 0x524d4157 wan_device [in wanrouter.h pre 3.9] -SAVEKMSG_MAGIC1 0x53415645 savekmsg arch/*/amiga/config.c -GDA_MAGIC 0x58464552 gda arch/mips/include/asm/sn/gda.h -RED_MAGIC1 0x5a2cf071 (any) mm/slab.c -EEPROM_MAGIC_VALUE 0x5ab478d2 lanai_dev drivers/atm/lanai.c -HDLCDRV_MAGIC 0x5ac6e778 hdlcdrv_state include/linux/hdlcdrv.h -PCXX_MAGIC 0x5c6df104 channel drivers/char/pcxx.h -KV_MAGIC 0x5f4b565f kernel_vars_s arch/mips/include/asm/sn/klkernvars.h -I810_STATE_MAGIC 0x63657373 i810_state sound/oss/i810_audio.c -TRIDENT_STATE_MAGIC 0x63657373 trient_state sound/oss/trident.c -M3_CARD_MAGIC 0x646e6f50 m3_card sound/oss/maestro3.c -FW_HEADER_MAGIC 0x65726F66 fw_header drivers/atm/fore200e.h -SLOT_MAGIC 0x67267321 slot drivers/hotplug/cpqphp.h -SLOT_MAGIC 0x67267322 slot drivers/hotplug/acpiphp.h -LO_MAGIC 0x68797548 nbd_device include/linux/nbd.h -OPROFILE_MAGIC 0x6f70726f super_block drivers/oprofile/oprofilefs.h -M3_STATE_MAGIC 0x734d724d m3_state sound/oss/maestro3.c -VMALLOC_MAGIC 0x87654320 snd_alloc_track sound/core/memory.c -KMALLOC_MAGIC 0x87654321 snd_alloc_track sound/core/memory.c -PWC_MAGIC 0x89DC10AB pwc_device drivers/usb/media/pwc.h -NBD_REPLY_MAGIC 0x96744668 nbd_reply include/linux/nbd.h -ENI155_MAGIC 0xa54b872d midway_eprom drivers/atm/eni.h -CODA_MAGIC 0xC0DAC0DA coda_file_info fs/coda/coda_fs_i.h -DPMEM_MAGIC 0xc0ffee11 gdt_pci_sram drivers/scsi/gdth.h -YAM_MAGIC 0xF10A7654 yam_port drivers/net/hamradio/yam.c -CCB_MAGIC 0xf2691ad2 ccb drivers/scsi/ncr53c8xx.c -QUEUE_MAGIC_FREE 0xf7e1c9a3 queue_entry drivers/scsi/arm/queue.c -QUEUE_MAGIC_USED 0xf7e1cc33 queue_entry drivers/scsi/arm/queue.c -HTB_CMAGIC 0xFEFAFEF1 htb_class net/sched/sch_htb.c -NMI_MAGIC 0x48414d4d455201 nmi_s arch/mips/include/asm/sn/nmi.h - -Note that there are also defined special per-driver magic numbers in sound -memory management. See include/sound/sndmagic.h for complete list of them. Many -OSS sound drivers have their magic numbers constructed from the soundcard PCI -ID - these are not listed here as well. - -IrDA subsystem also uses large number of own magic numbers, see -include/net/irda/irda.h for a complete list of them. - -HFS is another larger user of magic numbers - you can find them in -fs/hfs/hfs.h. diff --git a/Documentation/media/uapi/v4l/diff-v4l.rst b/Documentation/media/uapi/v4l/diff-v4l.rst index 76b2eca..8209eeb 100644 --- a/Documentation/media/uapi/v4l/diff-v4l.rst +++ b/Documentation/media/uapi/v4l/diff-v4l.rst @@ -648,12 +648,12 @@ microcode programming. A new interface for MPEG compression and playback devices is documented in :ref:`extended-controls`. .. [#f1] - According to Documentation/devices.txt these should be symbolic links + According to Documentation/admin-guide/devices.rst these should be symbolic links to ``/dev/video0``. Note the original bttv interface is not compatible with V4L or V4L2. .. [#f2] - According to ``Documentation/devices.txt`` a symbolic link to + According to ``Documentation/admin-guide/devices.rst`` a symbolic link to ``/dev/radio0``. .. [#f3] diff --git a/Documentation/media/v4l-drivers/bttv.rst b/Documentation/media/v4l-drivers/bttv.rst index 7abc1c9..bc63b12 100644 --- a/Documentation/media/v4l-drivers/bttv.rst +++ b/Documentation/media/v4l-drivers/bttv.rst @@ -304,10 +304,10 @@ bug. It is very helpful if you can tell where exactly it broke With a hard freeze you probably doesn't find anything in the logfiles. The only way to capture any kernel messages is to hook up a serial console and let some terminal application log the messages. /me uses -screen. See Documentation/serial-console.txt for details on setting +screen. See Documentation/admin-guide/serial-console.rst for details on setting up a serial console. -Read Documentation/oops-tracing.txt to learn how to get any useful +Read Documentation/admin-guide/oops-tracing.rst to learn how to get any useful information out of a register+stack dump printed by the kernel on protection faults (so-called "kernel oops"). diff --git a/Documentation/memory-hotplug.txt b/Documentation/memory-hotplug.txt index 0d7cb95..5de846d 100644 --- a/Documentation/memory-hotplug.txt +++ b/Documentation/memory-hotplug.txt @@ -324,7 +324,7 @@ guarantee that the memory block contains only migratable pages. Now, a boot option for making a memory block which consists of migratable pages is supported. By specifying "kernelcore=" or "movablecore=" boot option, you can create ZONE_MOVABLE...a zone which is just used for movable pages. -(See also Documentation/kernel-parameters.txt) +(See also Documentation/admin-guide/kernel-parameters.rst) Assume the system has "TOTAL" amount of memory at boot time, this boot option creates ZONE_MOVABLE as following. diff --git a/Documentation/networking/netconsole.txt b/Documentation/networking/netconsole.txt index 30409a3..296ea00 100644 --- a/Documentation/networking/netconsole.txt +++ b/Documentation/networking/netconsole.txt @@ -200,7 +200,7 @@ priority messages to the console. You can change this at runtime using: or by specifying "debug" on the kernel command line at boot, to send all kernel messages to the console. A specific value for this parameter can also be set using the "loglevel" kernel boot option. See the -dmesg(8) man page and Documentation/kernel-parameters.txt for details. +dmesg(8) man page and Documentation/admin-guide/kernel-parameters.rst for details. Netconsole was designed to be as instantaneous as possible, to enable the logging of even the most critical kernel bugs. It works diff --git a/Documentation/networking/netdev-FAQ.txt b/Documentation/networking/netdev-FAQ.txt index 0fe1c6e..cdebc5c 100644 --- a/Documentation/networking/netdev-FAQ.txt +++ b/Documentation/networking/netdev-FAQ.txt @@ -136,14 +136,14 @@ A: Normally Greg Kroah-Hartman collects stable commits himself, but Q: I see a network patch and I think it should be backported to stable. Should I request it via "stable@vger.kernel.org" like the references in - the kernel's Documentation/stable_kernel_rules.txt file say? + the kernel's Documentation/process/stable-kernel-rules.rst file say? A: No, not for networking. Check the stable queues as per above 1st to see if it is already queued. If not, then send a mail to netdev, listing the upstream commit ID and why you think it should be a stable candidate. Before you jump to go do the above, do note that the normal stable rules - in Documentation/stable_kernel_rules.txt still apply. So you need to + in Documentation/process/stable-kernel-rules.rst still apply. So you need to explicitly indicate why it is a critical fix and exactly what users are impacted. In addition, you need to convince yourself that you _really_ think it has been overlooked, vs. having been considered and rejected. @@ -165,7 +165,7 @@ A: No. See above answer. In short, if you think it really belongs in If you think there is some valid information relating to it being in stable that does _not_ belong in the commit log, then use the three - dash marker line as described in Documentation/SubmittingPatches to + dash marker line as described in Documentation/process/submitting-patches.rst to temporarily embed that information into the patch that you send. Q: Someone said that the comment style and coding convention is different @@ -220,5 +220,5 @@ A: Attention to detail. Re-read your own work as if you were the If it is your first patch, mail it to yourself so you can test apply it to an unpatched tree to confirm infrastructure didn't mangle it. - Finally, go back and read Documentation/SubmittingPatches to be + Finally, go back and read Documentation/process/submitting-patches.rst to be sure you are not repeating some common mistake documented there. diff --git a/Documentation/networking/vortex.txt b/Documentation/networking/vortex.txt index 97282da..ad3dead 100644 --- a/Documentation/networking/vortex.txt +++ b/Documentation/networking/vortex.txt @@ -364,7 +364,7 @@ steps you should take: - The contents of your report will vary a lot depending upon the problem. If it's a kernel crash then you should refer to the - REPORTING-BUGS file. + admin-guide/reporting-bugs.rst file. But for most problems it is useful to provide the following: diff --git a/Documentation/parport.txt b/Documentation/parport.txt deleted file mode 100644 index c208e43..0000000 --- a/Documentation/parport.txt +++ /dev/null @@ -1,267 +0,0 @@ -The `parport' code provides parallel-port support under Linux. This -includes the ability to share one port between multiple device -drivers. - -You can pass parameters to the parport code to override its automatic -detection of your hardware. This is particularly useful if you want -to use IRQs, since in general these can't be autoprobed successfully. -By default IRQs are not used even if they _can_ be probed. This is -because there are a lot of people using the same IRQ for their -parallel port and a sound card or network card. - -The parport code is split into two parts: generic (which deals with -port-sharing) and architecture-dependent (which deals with actually -using the port). - - -Parport as modules -================== - -If you load the parport code as a module, say - - # insmod parport - -to load the generic parport code. You then must load the -architecture-dependent code with (for example): - - # insmod parport_pc io=0x3bc,0x378,0x278 irq=none,7,auto - -to tell the parport code that you want three PC-style ports, one at -0x3bc with no IRQ, one at 0x378 using IRQ 7, and one at 0x278 with an -auto-detected IRQ. Currently, PC-style (parport_pc), Sun `bpp', -Amiga, Atari, and MFC3 hardware is supported. - -PCI parallel I/O card support comes from parport_pc. Base I/O -addresses should not be specified for supported PCI cards since they -are automatically detected. - - -modprobe --------- - -If you use modprobe , you will find it useful to add lines as below to a -configuration file in /etc/modprobe.d/ directory:. - - alias parport_lowlevel parport_pc - options parport_pc io=0x378,0x278 irq=7,auto - -modprobe will load parport_pc (with the options "io=0x378,0x278 irq=7,auto") -whenever a parallel port device driver (such as lp) is loaded. - -Note that these are example lines only! You shouldn't in general need -to specify any options to parport_pc in order to be able to use a -parallel port. - - -Parport probe [optional] -------------- - -In 2.2 kernels there was a module called parport_probe, which was used -for collecting IEEE 1284 device ID information. This has now been -enhanced and now lives with the IEEE 1284 support. When a parallel -port is detected, the devices that are connected to it are analysed, -and information is logged like this: - - parport0: Printer, BJC-210 (Canon) - -The probe information is available from files in /proc/sys/dev/parport/. - - -Parport linked into the kernel statically -========================================= - -If you compile the parport code into the kernel, then you can use -kernel boot parameters to get the same effect. Add something like the -following to your LILO command line: - - parport=0x3bc parport=0x378,7 parport=0x278,auto,nofifo - -You can have many `parport=...' statements, one for each port you want -to add. Adding `parport=0' to the kernel command-line will disable -parport support entirely. Adding `parport=auto' to the kernel -command-line will make parport use any IRQ lines or DMA channels that -it auto-detects. - - -Files in /proc -============== - -If you have configured the /proc filesystem into your kernel, you will -see a new directory entry: /proc/sys/dev/parport. In there will be a -directory entry for each parallel port for which parport is -configured. In each of those directories are a collection of files -describing that parallel port. - -The /proc/sys/dev/parport directory tree looks like: - -parport -|-- default -| |-- spintime -| `-- timeslice -|-- parport0 -| |-- autoprobe -| |-- autoprobe0 -| |-- autoprobe1 -| |-- autoprobe2 -| |-- autoprobe3 -| |-- devices -| | |-- active -| | `-- lp -| | `-- timeslice -| |-- base-addr -| |-- irq -| |-- dma -| |-- modes -| `-- spintime -`-- parport1 - |-- autoprobe - |-- autoprobe0 - |-- autoprobe1 - |-- autoprobe2 - |-- autoprobe3 - |-- devices - | |-- active - | `-- ppa - | `-- timeslice - |-- base-addr - |-- irq - |-- dma - |-- modes - `-- spintime - - -File: Contents: - -devices/active A list of the device drivers using that port. A "+" - will appear by the name of the device currently using - the port (it might not appear against any). The - string "none" means that there are no device drivers - using that port. - -base-addr Parallel port's base address, or addresses if the port - has more than one in which case they are separated - with tabs. These values might not have any sensible - meaning for some ports. - -irq Parallel port's IRQ, or -1 if none is being used. - -dma Parallel port's DMA channel, or -1 if none is being - used. - -modes Parallel port's hardware modes, comma-separated, - meaning: - - PCSPP PC-style SPP registers are available. - TRISTATE Port is bidirectional. - COMPAT Hardware acceleration for printers is - available and will be used. - EPP Hardware acceleration for EPP protocol - is available and will be used. - ECP Hardware acceleration for ECP protocol - is available and will be used. - DMA DMA is available and will be used. - - Note that the current implementation will only take - advantage of COMPAT and ECP modes if it has an IRQ - line to use. - -autoprobe Any IEEE-1284 device ID information that has been - acquired from the (non-IEEE 1284.3) device. - -autoprobe[0-3] IEEE 1284 device ID information retrieved from - daisy-chain devices that conform to IEEE 1284.3. - -spintime The number of microseconds to busy-loop while waiting - for the peripheral to respond. You might find that - adjusting this improves performance, depending on your - peripherals. This is a port-wide setting, i.e. it - applies to all devices on a particular port. - -timeslice The number of milliseconds that a device driver is - allowed to keep a port claimed for. This is advisory, - and driver can ignore it if it must. - -default/* The defaults for spintime and timeslice. When a new - port is registered, it picks up the default spintime. - When a new device is registered, it picks up the - default timeslice. - -Device drivers -============== - -Once the parport code is initialised, you can attach device drivers to -specific ports. Normally this happens automatically; if the lp driver -is loaded it will create one lp device for each port found. You can -override this, though, by using parameters either when you load the lp -driver: - - # insmod lp parport=0,2 - -or on the LILO command line: - - lp=parport0 lp=parport2 - -Both the above examples would inform lp that you want /dev/lp0 to be -the first parallel port, and /dev/lp1 to be the _third_ parallel port, -with no lp device associated with the second port (parport1). Note -that this is different to the way older kernels worked; there used to -be a static association between the I/O port address and the device -name, so /dev/lp0 was always the port at 0x3bc. This is no longer the -case - if you only have one port, it will default to being /dev/lp0, -regardless of base address. - -Also: - - * If you selected the IEEE 1284 support at compile time, you can say - `lp=auto' on the kernel command line, and lp will create devices - only for those ports that seem to have printers attached. - - * If you give PLIP the `timid' parameter, either with `plip=timid' on - the command line, or with `insmod plip timid=1' when using modules, - it will avoid any ports that seem to be in use by other devices. - - * IRQ autoprobing works only for a few port types at the moment. - -Reporting printer problems with parport -======================================= - -If you are having problems printing, please go through these steps to -try to narrow down where the problem area is. - -When reporting problems with parport, really you need to give all of -the messages that parport_pc spits out when it initialises. There are -several code paths: - -o polling -o interrupt-driven, protocol in software -o interrupt-driven, protocol in hardware using PIO -o interrupt-driven, protocol in hardware using DMA - -The kernel messages that parport_pc logs give an indication of which -code path is being used. (They could be a lot better actually..) - -For normal printer protocol, having IEEE 1284 modes enabled or not -should not make a difference. - -To turn off the 'protocol in hardware' code paths, disable -CONFIG_PARPORT_PC_FIFO. Note that when they are enabled they are not -necessarily _used_; it depends on whether the hardware is available, -enabled by the BIOS, and detected by the driver. - -So, to start with, disable CONFIG_PARPORT_PC_FIFO, and load parport_pc -with 'irq=none'. See if printing works then. It really should, -because this is the simplest code path. - -If that works fine, try with 'io=0x378 irq=7' (adjust for your -hardware), to make it use interrupt-driven in-software protocol. - -If _that_ works fine, then one of the hardware modes isn't working -right. Enable CONFIG_PARPORT_PC_FIFO (no, it isn't a module option, -and yes, it should be), set the port to ECP mode in the BIOS and note -the DMA channel, and try with: - - io=0x378 irq=7 dma=none (for PIO) - io=0x378 irq=7 dma=3 (for DMA) --- -philb@gnu.org -tim@cyberelk.net diff --git a/Documentation/power/00-INDEX b/Documentation/power/00-INDEX index ad04cc8..7cb6085 100644 --- a/Documentation/power/00-INDEX +++ b/Documentation/power/00-INDEX @@ -6,7 +6,7 @@ basic-pm-debugging.txt - Debugging suspend and resume charger-manager.txt - Battery charger management. -devices.txt +admin-guide/devices.rst - How drivers interact with system-wide power management drivers-testing.txt - Testing suspend and resume support in device drivers diff --git a/Documentation/power/pci.txt b/Documentation/power/pci.txt index 4455888..85c746c 100644 --- a/Documentation/power/pci.txt +++ b/Documentation/power/pci.txt @@ -8,7 +8,7 @@ management. Based on previous work by Patrick Mochel <mochel@transmeta.com> This document only covers the aspects of power management specific to PCI devices. For general description of the kernel's interfaces related to device -power management refer to Documentation/power/devices.txt and +power management refer to Documentation/power/admin-guide/devices.rst and Documentation/power/runtime_pm.txt. --------------------------------------------------------------------------- @@ -417,7 +417,7 @@ pm->runtime_idle() callback. 2.4. System-Wide Power Transitions ---------------------------------- There are a few different types of system-wide power transitions, described in -Documentation/power/devices.txt. Each of them requires devices to be handled +Documentation/power/admin-guide/devices.rst. Each of them requires devices to be handled in a specific way and the PM core executes subsystem-level power management callbacks for this purpose. They are executed in phases such that each phase involves executing the same subsystem-level callback for every device belonging @@ -623,7 +623,7 @@ System restore requires a hibernation image to be loaded into memory and the pre-hibernation memory contents to be restored before the pre-hibernation system activity can be resumed. -As described in Documentation/power/devices.txt, the hibernation image is loaded +As described in Documentation/power/admin-guide/devices.rst, the hibernation image is loaded into memory by a fresh instance of the kernel, called the boot kernel, which in turn is loaded and run by a boot loader in the usual way. After the boot kernel has loaded the image, it needs to replace its own code and data with the code @@ -677,7 +677,7 @@ controlling the runtime power management of their devices. At the time of this writing there are two ways to define power management callbacks for a PCI device driver, the recommended one, based on using a -dev_pm_ops structure described in Documentation/power/devices.txt, and the +dev_pm_ops structure described in Documentation/power/admin-guide/devices.rst, and the "legacy" one, in which the .suspend(), .suspend_late(), .resume_early(), and .resume() callbacks from struct pci_driver are used. The legacy approach, however, doesn't allow one to define runtime power management callbacks and is @@ -1046,5 +1046,5 @@ PCI Local Bus Specification, Rev. 3.0 PCI Bus Power Management Interface Specification, Rev. 1.2 Advanced Configuration and Power Interface (ACPI) Specification, Rev. 3.0b PCI Express Base Specification, Rev. 2.0 -Documentation/power/devices.txt +Documentation/power/admin-guide/devices.rst Documentation/power/runtime_pm.txt diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 1fd1fbe..4870980 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -674,7 +674,7 @@ left in runtime suspend. If that happens, the PM core will not execute any system suspend and resume callbacks for all of those devices, except for the complete callback, which is then entirely responsible for handling the device as appropriate. This only applies to system suspend transitions that are not -related to hibernation (see Documentation/power/devices.txt for more +related to hibernation (see Documentation/power/admin-guide/devices.rst for more information). The PM core does its best to reduce the probability of race conditions between diff --git a/Documentation/power/swsusp-dmcrypt.txt b/Documentation/power/swsusp-dmcrypt.txt index 59931b4..b802fbf 100644 --- a/Documentation/power/swsusp-dmcrypt.txt +++ b/Documentation/power/swsusp-dmcrypt.txt @@ -8,7 +8,7 @@ Some prerequisites: You know how dm-crypt works. If not, visit the following web page: http://www.saout.de/misc/dm-crypt/ You have read Documentation/power/swsusp.txt and understand it. -You did read Documentation/initrd.txt and know how an initrd works. +You did read Documentation/admin-guide/initrd.rst and know how an initrd works. You know how to create or how to modify an initrd. Now your system is properly set up, your disk is encrypted except for diff --git a/Documentation/development-process/1.Intro.rst b/Documentation/process/1.Intro.rst index 22642b3..22642b3 100644 --- a/Documentation/development-process/1.Intro.rst +++ b/Documentation/process/1.Intro.rst diff --git a/Documentation/development-process/2.Process.rst b/Documentation/process/2.Process.rst index ce5561b..ce5561b 100644 --- a/Documentation/development-process/2.Process.rst +++ b/Documentation/process/2.Process.rst diff --git a/Documentation/development-process/3.Early-stage.rst b/Documentation/process/3.Early-stage.rst index af2c0af..af2c0af 100644 --- a/Documentation/development-process/3.Early-stage.rst +++ b/Documentation/process/3.Early-stage.rst diff --git a/Documentation/development-process/4.Coding.rst b/Documentation/process/4.Coding.rst index 9d5cef9..983d628 100644 --- a/Documentation/development-process/4.Coding.rst +++ b/Documentation/process/4.Coding.rst @@ -22,7 +22,7 @@ Coding style ************ The kernel has long had a standard coding style, described in -Documentation/CodingStyle. For much of that time, the policies described +Documentation/process/coding-style.rst. For much of that time, the policies described in that file were taken as being, at most, advisory. As a result, there is a substantial amount of code in the kernel which does not meet the coding style guidelines. The presence of that code leads to two independent @@ -343,7 +343,7 @@ user-space developers to know what they are working with. See Documentation/ABI/README for a description of how this documentation should be formatted and what information needs to be provided. -The file Documentation/kernel-parameters.txt describes all of the kernel's +The file Documentation/admin-guide/kernel-parameters.rst describes all of the kernel's boot-time parameters. Any patch which adds new parameters should add the appropriate entries to this file. diff --git a/Documentation/development-process/5.Posting.rst b/Documentation/process/5.Posting.rst index b511ddf..1b7728b 100644 --- a/Documentation/development-process/5.Posting.rst +++ b/Documentation/process/5.Posting.rst @@ -9,8 +9,8 @@ kernel. Unsurprisingly, the kernel development community has evolved a set of conventions and procedures which are used in the posting of patches; following them will make life much easier for everybody involved. This document will attempt to cover these expectations in reasonable detail; -more information can also be found in the files SubmittingPatches, -SubmittingDrivers, and SubmitChecklist in the kernel documentation +more information can also be found in the files process/submitting-patches.rst, +process/submitting-drivers.rst, and process/submit-checklist.rst in the kernel documentation directory. @@ -198,7 +198,7 @@ pass it to diff with the "-X" option. The tags mentioned above are used to describe how various developers have been associated with the development of this patch. They are described in -detail in the SubmittingPatches document; what follows here is a brief +detail in the process/submitting-patches.rst document; what follows here is a brief summary. Each of these lines has the format: :: @@ -210,7 +210,7 @@ The tags in common use are: - Signed-off-by: this is a developer's certification that he or she has the right to submit the patch for inclusion into the kernel. It is an agreement to the Developer's Certificate of Origin, the full text of - which can be found in Documentation/SubmittingPatches. Code without a + which can be found in Documentation/process/submitting-patches.rst. Code without a proper signoff cannot be merged into the mainline. - Acked-by: indicates an agreement by another developer (often a @@ -221,7 +221,7 @@ The tags in common use are: it to work. - Reviewed-by: the named developer has reviewed the patch for correctness; - see the reviewer's statement in Documentation/SubmittingPatches for more + see the reviewer's statement in Documentation/process/submitting-patches.rst for more detail. - Reported-by: names a user who reported a problem which is fixed by this @@ -248,7 +248,7 @@ take care of: be examined in any detail. If there is any doubt at all, mail the patch to yourself and convince yourself that it shows up intact. - Documentation/email-clients.txt has some helpful hints on making + Documentation/process/email-clients.rst has some helpful hints on making specific mail clients work for sending patches. - Are you sure your patch is free of silly mistakes? You should always diff --git a/Documentation/development-process/6.Followthrough.rst b/Documentation/process/6.Followthrough.rst index a173cd5..a173cd5 100644 --- a/Documentation/development-process/6.Followthrough.rst +++ b/Documentation/process/6.Followthrough.rst diff --git a/Documentation/development-process/7.AdvancedTopics.rst b/Documentation/process/7.AdvancedTopics.rst index 81d61c5..172733c 100644 --- a/Documentation/development-process/7.AdvancedTopics.rst +++ b/Documentation/process/7.AdvancedTopics.rst @@ -176,5 +176,3 @@ security issues, duplication of code found elsewhere, adequate documentation, adverse effects on performance, user-space ABI changes, etc. All types of review, if they lead to better code going into the kernel, are welcome and worthwhile. - - diff --git a/Documentation/development-process/8.Conclusion.rst b/Documentation/process/8.Conclusion.rst index 23ec7cb..1c7f54c 100644 --- a/Documentation/development-process/8.Conclusion.rst +++ b/Documentation/process/8.Conclusion.rst @@ -5,9 +5,9 @@ For more information There are numerous sources of information on Linux kernel development and related topics. First among those will always be the Documentation -directory found in the kernel source distribution. The top-level HOWTO -file is an important starting point; SubmittingPatches and -SubmittingDrivers are also something which all kernel developers should +directory found in the kernel source distribution. The top-level process/howto.rst +file is an important starting point; process/submitting-patches.rst and +process/submitting-drivers.rst are also something which all kernel developers should read. Many internal kernel APIs are documented using the kerneldoc mechanism; "make htmldocs" or "make pdfdocs" can be used to generate those documents in HTML or PDF format (though the version of TeX shipped by some diff --git a/Documentation/adding-syscalls.txt b/Documentation/process/adding-syscalls.rst index bbb31e0..8cc25a0 100644 --- a/Documentation/adding-syscalls.txt +++ b/Documentation/process/adding-syscalls.rst @@ -3,7 +3,7 @@ Adding a New System Call This document describes what's involved in adding a new system call to the Linux kernel, over and above the normal submission advice in -Documentation/SubmittingPatches. +:ref:`Documentation/process/submitting-patches.rst <submittingpatches>`. System Call Alternatives @@ -19,30 +19,33 @@ interface. object, it may make more sense to create a new filesystem or device. This also makes it easier to encapsulate the new functionality in a kernel module rather than requiring it to be built into the main kernel. + - If the new functionality involves operations where the kernel notifies userspace that something has happened, then returning a new file descriptor for the relevant object allows userspace to use - poll/select/epoll to receive that notification. - - However, operations that don't map to read(2)/write(2)-like operations - have to be implemented as ioctl(2) requests, which can lead to a - somewhat opaque API. + ``poll``/``select``/``epoll`` to receive that notification. + - However, operations that don't map to + :manpage:`read(2)`/:manpage:`write(2)`-like operations + have to be implemented as :manpage:`ioctl(2)` requests, which can lead + to a somewhat opaque API. + - If you're just exposing runtime system information, a new node in sysfs - (see Documentation/filesystems/sysfs.txt) or the /proc filesystem may be - more appropriate. However, access to these mechanisms requires that the + (see ``Documentation/filesystems/sysfs.txt``) or the ``/proc`` filesystem may + be more appropriate. However, access to these mechanisms requires that the relevant filesystem is mounted, which might not always be the case (e.g. in a namespaced/sandboxed/chrooted environment). Avoid adding any API to debugfs, as this is not considered a 'production' interface to userspace. - If the operation is specific to a particular file or file descriptor, then - an additional fcntl(2) command option may be more appropriate. However, - fcntl(2) is a multiplexing system call that hides a lot of complexity, so + an additional :manpage:`fcntl(2)` command option may be more appropriate. However, + :manpage:`fcntl(2)` is a multiplexing system call that hides a lot of complexity, so this option is best for when the new function is closely analogous to - existing fcntl(2) functionality, or the new functionality is very simple + existing :manpage:`fcntl(2)` functionality, or the new functionality is very simple (for example, getting/setting a simple flag related to a file descriptor). - If the operation is specific to a particular task or process, then an - additional prctl(2) command option may be more appropriate. As with - fcntl(2), this system call is a complicated multiplexor so is best reserved - for near-analogs of existing prctl() commands or getting/setting a simple - flag related to a process. + additional :manpage:`prctl(2)` command option may be more appropriate. As + with :manpage:`fcntl(2)`, this system call is a complicated multiplexor so + is best reserved for near-analogs of existing ``prctl()`` commands or + getting/setting a simple flag related to a process. Designing the API: Planning for Extension @@ -54,15 +57,16 @@ interface on the kernel mailing list, and it's important to plan for future extensions of the interface. (The syscall table is littered with historical examples where this wasn't done, -together with the corresponding follow-up system calls -- eventfd/eventfd2, -dup2/dup3, inotify_init/inotify_init1, pipe/pipe2, renameat/renameat2 -- so +together with the corresponding follow-up system calls -- +``eventfd``/``eventfd2``, ``dup2``/``dup3``, ``inotify_init``/``inotify_init1``, +``pipe``/``pipe2``, ``renameat``/``renameat2`` -- so learn from the history of the kernel and plan for extensions from the start.) For simpler system calls that only take a couple of arguments, the preferred way to allow for future extensibility is to include a flags argument to the system call. To make sure that userspace programs can safely use flags between kernel versions, check whether the flags value holds any unknown -flags, and reject the system call (with EINVAL) if it does: +flags, and reject the system call (with ``EINVAL``) if it does:: if (flags & ~(THING_FLAG1 | THING_FLAG2 | THING_FLAG3)) return -EINVAL; @@ -72,7 +76,7 @@ flags, and reject the system call (with EINVAL) if it does: For more sophisticated system calls that involve a larger number of arguments, it's preferred to encapsulate the majority of the arguments into a structure that is passed in by pointer. Such a structure can cope with future extension -by including a size argument in the structure: +by including a size argument in the structure:: struct xyzzy_params { u32 size; /* userspace sets p->size = sizeof(struct xyzzy_params) */ @@ -81,19 +85,19 @@ by including a size argument in the structure: u64 param_3; }; -As long as any subsequently added field, say param_4, is designed so that a +As long as any subsequently added field, say ``param_4``, is designed so that a zero value gives the previous behaviour, then this allows both directions of version mismatch: - To cope with a later userspace program calling an older kernel, the kernel code should check that any memory beyond the size of the structure that it - expects is zero (effectively checking that param_4 == 0). + expects is zero (effectively checking that ``param_4 == 0``). - To cope with an older userspace program calling a newer kernel, the kernel code can zero-extend a smaller instance of the structure (effectively - setting param_4 = 0). + setting ``param_4 = 0``). -See perf_event_open(2) and the perf_copy_attr() function (in -kernel/events/core.c) for an example of this approach. +See :manpage:`perf_event_open(2)` and the ``perf_copy_attr()`` function (in +``kernel/events/core.c``) for an example of this approach. Designing the API: Other Considerations @@ -104,57 +108,60 @@ should use a file descriptor as the handle for that object -- don't invent a new type of userspace object handle when the kernel already has mechanisms and well-defined semantics for using file descriptors. -If your new xyzzy(2) system call does return a new file descriptor, then the -flags argument should include a value that is equivalent to setting O_CLOEXEC -on the new FD. This makes it possible for userspace to close the timing -window between xyzzy() and calling fcntl(fd, F_SETFD, FD_CLOEXEC), where an -unexpected fork() and execve() in another thread could leak a descriptor to +If your new :manpage:`xyzzy(2)` system call does return a new file descriptor, +then the flags argument should include a value that is equivalent to setting +``O_CLOEXEC`` on the new FD. This makes it possible for userspace to close +the timing window between ``xyzzy()`` and calling +``fcntl(fd, F_SETFD, FD_CLOEXEC)``, where an unexpected ``fork()`` and +``execve()`` in another thread could leak a descriptor to the exec'ed program. (However, resist the temptation to re-use the actual value -of the O_CLOEXEC constant, as it is architecture-specific and is part of a -numbering space of O_* flags that is fairly full.) +of the ``O_CLOEXEC`` constant, as it is architecture-specific and is part of a +numbering space of ``O_*`` flags that is fairly full.) If your system call returns a new file descriptor, you should also consider -what it means to use the poll(2) family of system calls on that file +what it means to use the :manpage:`poll(2)` family of system calls on that file descriptor. Making a file descriptor ready for reading or writing is the normal way for the kernel to indicate to userspace that an event has occurred on the corresponding kernel object. -If your new xyzzy(2) system call involves a filename argument: +If your new :manpage:`xyzzy(2)` system call involves a filename argument:: int sys_xyzzy(const char __user *path, ..., unsigned int flags); -you should also consider whether an xyzzyat(2) version is more appropriate: +you should also consider whether an :manpage:`xyzzyat(2)` version is more appropriate:: int sys_xyzzyat(int dfd, const char __user *path, ..., unsigned int flags); This allows more flexibility for how userspace specifies the file in question; in particular it allows userspace to request the functionality for an -already-opened file descriptor using the AT_EMPTY_PATH flag, effectively giving -an fxyzzy(3) operation for free: +already-opened file descriptor using the ``AT_EMPTY_PATH`` flag, effectively +giving an :manpage:`fxyzzy(3)` operation for free:: - xyzzyat(AT_FDCWD, path, ..., 0) is equivalent to xyzzy(path,...) - xyzzyat(fd, "", ..., AT_EMPTY_PATH) is equivalent to fxyzzy(fd, ...) -(For more details on the rationale of the *at() calls, see the openat(2) man -page; for an example of AT_EMPTY_PATH, see the fstatat(2) man page.) - -If your new xyzzy(2) system call involves a parameter describing an offset -within a file, make its type loff_t so that 64-bit offsets can be supported -even on 32-bit architectures. - -If your new xyzzy(2) system call involves privileged functionality, it needs -to be governed by the appropriate Linux capability bit (checked with a call to -capable()), as described in the capabilities(7) man page. Choose an existing -capability bit that governs related functionality, but try to avoid combining -lots of only vaguely related functions together under the same bit, as this -goes against capabilities' purpose of splitting the power of root. In -particular, avoid adding new uses of the already overly-general CAP_SYS_ADMIN -capability. - -If your new xyzzy(2) system call manipulates a process other than the calling -process, it should be restricted (using a call to ptrace_may_access()) so that -only a calling process with the same permissions as the target process, or -with the necessary capabilities, can manipulate the target process. +(For more details on the rationale of the \*at() calls, see the +:manpage:`openat(2)` man page; for an example of AT_EMPTY_PATH, see the +:manpage:`fstatat(2)` man page.) + +If your new :manpage:`xyzzy(2)` system call involves a parameter describing an +offset within a file, make its type ``loff_t`` so that 64-bit offsets can be +supported even on 32-bit architectures. + +If your new :manpage:`xyzzy(2)` system call involves privileged functionality, +it needs to be governed by the appropriate Linux capability bit (checked with +a call to ``capable()``), as described in the :manpage:`capabilities(7)` man +page. Choose an existing capability bit that governs related functionality, +but try to avoid combining lots of only vaguely related functions together +under the same bit, as this goes against capabilities' purpose of splitting +the power of root. In particular, avoid adding new uses of the already +overly-general ``CAP_SYS_ADMIN`` capability. + +If your new :manpage:`xyzzy(2)` system call manipulates a process other than +the calling process, it should be restricted (using a call to +``ptrace_may_access()``) so that only a calling process with the same +permissions as the target process, or with the necessary capabilities, can +manipulate the target process. Finally, be aware that some non-x86 architectures have an easier time if system call parameters that are explicitly 64-bit fall on odd-numbered @@ -175,7 +182,7 @@ distinct commits (each of which is described further below): - Wiring up of the new system call for one particular architecture, usually x86 (including all of x86_64, x86_32 and x32). - A demonstration of the use of the new system call in userspace via a - selftest in tools/testing/selftests/. + selftest in ``tools/testing/selftests/``. - A draft man-page for the new system call, either as plain text in the cover letter, or as a patch to the (separate) man-pages repository. @@ -186,24 +193,24 @@ be cc'ed to linux-api@vger.kernel.org. Generic System Call Implementation ---------------------------------- -The main entry point for your new xyzzy(2) system call will be called -sys_xyzzy(), but you add this entry point with the appropriate -SYSCALL_DEFINEn() macro rather than explicitly. The 'n' indicates the number -of arguments to the system call, and the macro takes the system call name +The main entry point for your new :manpage:`xyzzy(2)` system call will be called +``sys_xyzzy()``, but you add this entry point with the appropriate +``SYSCALL_DEFINEn()`` macro rather than explicitly. The 'n' indicates the +number of arguments to the system call, and the macro takes the system call name followed by the (type, name) pairs for the parameters as arguments. Using this macro allows metadata about the new system call to be made available for other tools. The new entry point also needs a corresponding function prototype, in -include/linux/syscalls.h, marked as asmlinkage to match the way that system -calls are invoked: +``include/linux/syscalls.h``, marked as asmlinkage to match the way that system +calls are invoked:: asmlinkage long sys_xyzzy(...); Some architectures (e.g. x86) have their own architecture-specific syscall tables, but several other architectures share a generic syscall table. Add your new system call to the generic list by adding an entry to the list in -include/uapi/asm-generic/unistd.h: +``include/uapi/asm-generic/unistd.h``:: #define __NR_xyzzy 292 __SYSCALL(__NR_xyzzy, sys_xyzzy) @@ -212,30 +219,30 @@ Also update the __NR_syscalls count to reflect the additional system call, and note that if multiple new system calls are added in the same merge window, your new syscall number may get adjusted to resolve conflicts. -The file kernel/sys_ni.c provides a fallback stub implementation of each system -call, returning -ENOSYS. Add your new system call here too: +The file ``kernel/sys_ni.c`` provides a fallback stub implementation of each +system call, returning ``-ENOSYS``. Add your new system call here too:: cond_syscall(sys_xyzzy); Your new kernel functionality, and the system call that controls it, should -normally be optional, so add a CONFIG option (typically to init/Kconfig) for -it. As usual for new CONFIG options: +normally be optional, so add a ``CONFIG`` option (typically to +``init/Kconfig``) for it. As usual for new ``CONFIG`` options: - Include a description of the new functionality and system call controlled by the option. - Make the option depend on EXPERT if it should be hidden from normal users. - Make any new source files implementing the function dependent on the CONFIG - option in the Makefile (e.g. "obj-$(CONFIG_XYZZY_SYSCALL) += xyzzy.c"). + option in the Makefile (e.g. ``obj-$(CONFIG_XYZZY_SYSCALL) += xyzzy.c``). - Double check that the kernel still builds with the new CONFIG option turned off. To summarize, you need a commit that includes: - - CONFIG option for the new function, normally in init/Kconfig - - SYSCALL_DEFINEn(xyzzy, ...) for the entry point - - corresponding prototype in include/linux/syscalls.h - - generic table entry in include/uapi/asm-generic/unistd.h - - fallback stub in kernel/sys_ni.c + - ``CONFIG`` option for the new function, normally in ``init/Kconfig`` + - ``SYSCALL_DEFINEn(xyzzy, ...)`` for the entry point + - corresponding prototype in ``include/linux/syscalls.h`` + - generic table entry in ``include/uapi/asm-generic/unistd.h`` + - fallback stub in ``kernel/sys_ni.c`` x86 System Call Implementation @@ -244,11 +251,11 @@ x86 System Call Implementation To wire up your new system call for x86 platforms, you need to update the master syscall tables. Assuming your new system call isn't special in some way (see below), this involves a "common" entry (for x86_64 and x32) in -arch/x86/entry/syscalls/syscall_64.tbl: +arch/x86/entry/syscalls/syscall_64.tbl:: 333 common xyzzy sys_xyzzy -and an "i386" entry in arch/x86/entry/syscalls/syscall_32.tbl: +and an "i386" entry in ``arch/x86/entry/syscalls/syscall_32.tbl``:: 380 i386 xyzzy sys_xyzzy @@ -267,48 +274,49 @@ However, there are a couple of situations where a compatibility layer is needed to cope with size differences between 32-bit and 64-bit. The first is if the 64-bit kernel also supports 32-bit userspace programs, and -so needs to parse areas of (__user) memory that could hold either 32-bit or +so needs to parse areas of (``__user``) memory that could hold either 32-bit or 64-bit values. In particular, this is needed whenever a system call argument is: - a pointer to a pointer - - a pointer to a struct containing a pointer (e.g. struct iovec __user *) - - a pointer to a varying sized integral type (time_t, off_t, long, ...) + - a pointer to a struct containing a pointer (e.g. ``struct iovec __user *``) + - a pointer to a varying sized integral type (``time_t``, ``off_t``, + ``long``, ...) - a pointer to a struct containing a varying sized integral type. The second situation that requires a compatibility layer is if one of the system call's arguments has a type that is explicitly 64-bit even on a 32-bit -architecture, for example loff_t or __u64. In this case, a value that arrives -at a 64-bit kernel from a 32-bit application will be split into two 32-bit -values, which then need to be re-assembled in the compatibility layer. +architecture, for example ``loff_t`` or ``__u64``. In this case, a value that +arrives at a 64-bit kernel from a 32-bit application will be split into two +32-bit values, which then need to be re-assembled in the compatibility layer. (Note that a system call argument that's a pointer to an explicit 64-bit type -does *not* need a compatibility layer; for example, splice(2)'s arguments of -type loff_t __user * do not trigger the need for a compat_ system call.) +does **not** need a compatibility layer; for example, :manpage:`splice(2)`'s arguments of +type ``loff_t __user *`` do not trigger the need for a ``compat_`` system call.) -The compatibility version of the system call is called compat_sys_xyzzy(), and -is added with the COMPAT_SYSCALL_DEFINEn() macro, analogously to +The compatibility version of the system call is called ``compat_sys_xyzzy()``, +and is added with the ``COMPAT_SYSCALL_DEFINEn()`` macro, analogously to SYSCALL_DEFINEn. This version of the implementation runs as part of a 64-bit kernel, but expects to receive 32-bit parameter values and does whatever is -needed to deal with them. (Typically, the compat_sys_ version converts the -values to 64-bit versions and either calls on to the sys_ version, or both of +needed to deal with them. (Typically, the ``compat_sys_`` version converts the +values to 64-bit versions and either calls on to the ``sys_`` version, or both of them call a common inner implementation function.) The compat entry point also needs a corresponding function prototype, in -include/linux/compat.h, marked as asmlinkage to match the way that system -calls are invoked: +``include/linux/compat.h``, marked as asmlinkage to match the way that system +calls are invoked:: asmlinkage long compat_sys_xyzzy(...); If the system call involves a structure that is laid out differently on 32-bit -and 64-bit systems, say struct xyzzy_args, then the include/linux/compat.h -header file should also include a compat version of the structure (struct -compat_xyzzy_args) where each variable-size field has the appropriate compat_ -type that corresponds to the type in struct xyzzy_args. The -compat_sys_xyzzy() routine can then use this compat_ structure to parse the -arguments from a 32-bit invocation. +and 64-bit systems, say ``struct xyzzy_args``, then the include/linux/compat.h +header file should also include a compat version of the structure (``struct +compat_xyzzy_args``) where each variable-size field has the appropriate +``compat_`` type that corresponds to the type in ``struct xyzzy_args``. The +``compat_sys_xyzzy()`` routine can then use this ``compat_`` structure to +parse the arguments from a 32-bit invocation. -For example, if there are fields: +For example, if there are fields:: struct xyzzy_args { const char __user *ptr; @@ -317,7 +325,7 @@ For example, if there are fields: /* ... */ }; -in struct xyzzy_args, then struct compat_xyzzy_args would have: +in struct xyzzy_args, then struct compat_xyzzy_args would have:: struct compat_xyzzy_args { compat_uptr_t ptr; @@ -327,18 +335,19 @@ in struct xyzzy_args, then struct compat_xyzzy_args would have: }; The generic system call list also needs adjusting to allow for the compat -version; the entry in include/uapi/asm-generic/unistd.h should use -__SC_COMP rather than __SYSCALL: +version; the entry in ``include/uapi/asm-generic/unistd.h`` should use +``__SC_COMP`` rather than ``__SYSCALL``:: #define __NR_xyzzy 292 __SC_COMP(__NR_xyzzy, sys_xyzzy, compat_sys_xyzzy) To summarize, you need: - - a COMPAT_SYSCALL_DEFINEn(xyzzy, ...) for the compat entry point - - corresponding prototype in include/linux/compat.h - - (if needed) 32-bit mapping struct in include/linux/compat.h - - instance of __SC_COMP not __SYSCALL in include/uapi/asm-generic/unistd.h + - a ``COMPAT_SYSCALL_DEFINEn(xyzzy, ...)`` for the compat entry point + - corresponding prototype in ``include/linux/compat.h`` + - (if needed) 32-bit mapping struct in ``include/linux/compat.h`` + - instance of ``__SC_COMP`` not ``__SYSCALL`` in + ``include/uapi/asm-generic/unistd.h`` Compatibility System Calls (x86) @@ -347,9 +356,9 @@ Compatibility System Calls (x86) To wire up the x86 architecture of a system call with a compatibility version, the entries in the syscall tables need to be adjusted. -First, the entry in arch/x86/entry/syscalls/syscall_32.tbl gets an extra +First, the entry in ``arch/x86/entry/syscalls/syscall_32.tbl`` gets an extra column to indicate that a 32-bit userspace program running on a 64-bit kernel -should hit the compat entry point: +should hit the compat entry point:: 380 i386 xyzzy sys_xyzzy compat_sys_xyzzy @@ -359,8 +368,8 @@ should either match the 64-bit version or the 32-bit version. If there's a pointer-to-a-pointer involved, the decision is easy: x32 is ILP32, so the layout should match the 32-bit version, and the entry in -arch/x86/entry/syscalls/syscall_64.tbl is split so that x32 programs hit the -compatibility wrapper: +``arch/x86/entry/syscalls/syscall_64.tbl`` is split so that x32 programs hit +the compatibility wrapper:: 333 64 xyzzy sys_xyzzy ... @@ -384,8 +393,9 @@ stack the same and most of the registers the same as before the system call, and with the same virtual memory space. However, a few system calls do things differently. They might return to a -different location (rt_sigreturn) or change the memory space (fork/vfork/clone) -or even architecture (execve/execveat) of the program. +different location (``rt_sigreturn``) or change the memory space +(``fork``/``vfork``/``clone``) or even architecture (``execve``/``execveat``) +of the program. To allow for this, the kernel implementation of the system call may need to save and restore additional registers to the kernel stack, allowing complete @@ -395,31 +405,31 @@ This is arch-specific, but typically involves defining assembly entry points that save/restore additional registers and invoke the real system call entry point. -For x86_64, this is implemented as a stub_xyzzy entry point in -arch/x86/entry/entry_64.S, and the entry in the syscall table -(arch/x86/entry/syscalls/syscall_64.tbl) is adjusted to match: +For x86_64, this is implemented as a ``stub_xyzzy`` entry point in +``arch/x86/entry/entry_64.S``, and the entry in the syscall table +(``arch/x86/entry/syscalls/syscall_64.tbl``) is adjusted to match:: 333 common xyzzy stub_xyzzy The equivalent for 32-bit programs running on a 64-bit kernel is normally -called stub32_xyzzy and implemented in arch/x86/entry/entry_64_compat.S, +called ``stub32_xyzzy`` and implemented in ``arch/x86/entry/entry_64_compat.S``, with the corresponding syscall table adjustment in -arch/x86/entry/syscalls/syscall_32.tbl: +``arch/x86/entry/syscalls/syscall_32.tbl``:: 380 i386 xyzzy sys_xyzzy stub32_xyzzy If the system call needs a compatibility layer (as in the previous section) -then the stub32_ version needs to call on to the compat_sys_ version of the -system call rather than the native 64-bit version. Also, if the x32 ABI +then the ``stub32_`` version needs to call on to the ``compat_sys_`` version +of the system call rather than the native 64-bit version. Also, if the x32 ABI implementation is not common with the x86_64 version, then its syscall -table will also need to invoke a stub that calls on to the compat_sys_ +table will also need to invoke a stub that calls on to the ``compat_sys_`` version. For completeness, it's also nice to set up a mapping so that user-mode Linux still works -- its syscall table will reference stub_xyzzy, but the UML build -doesn't include arch/x86/entry/entry_64.S implementation (because UML +doesn't include ``arch/x86/entry/entry_64.S`` implementation (because UML simulates registers etc). Fixing this is as simple as adding a #define to -arch/x86/um/sys_call_table_64.c: +``arch/x86/um/sys_call_table_64.c``:: #define stub_xyzzy sys_xyzzy @@ -432,9 +442,9 @@ occasional exception that may need updating for your particular system call. The audit subsystem is one such special case; it includes (arch-specific) functions that classify some special types of system call -- specifically -file open (open/openat), program execution (execve/exeveat) or socket -multiplexor (socketcall) operations. If your new system call is analogous to -one of these, then the audit system should be updated. +file open (``open``/``openat``), program execution (``execve``/``exeveat``) or +socket multiplexor (``socketcall``) operations. If your new system call is +analogous to one of these, then the audit system should be updated. More generally, if there is an existing system call that is analogous to your new system call, it's worth doing a kernel-wide grep for the existing system @@ -447,10 +457,10 @@ Testing A new system call should obviously be tested; it is also useful to provide reviewers with a demonstration of how user space programs will use the system call. A good way to combine these aims is to include a simple self-test -program in a new directory under tools/testing/selftests/. +program in a new directory under ``tools/testing/selftests/``. For a new system call, there will obviously be no libc wrapper function and so -the test will need to invoke it using syscall(); also, if the system call +the test will need to invoke it using ``syscall()``; also, if the system call involves a new userspace-visible structure, the corresponding header will need to be installed to compile the test. @@ -461,6 +471,7 @@ and x32 (-mx32) ABI program. For more extensive and thorough testing of new functionality, you should also consider adding tests to the Linux Test Project, or to the xfstests project for filesystem-related changes. + - https://linux-test-project.github.io/ - git://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git @@ -487,12 +498,14 @@ References and Sources arguments: https://lwn.net/Articles/311630/ - Pair of LWN articles from David Drysdale that describe the system call implementation paths in detail for v3.14: + - https://lwn.net/Articles/604287/ - https://lwn.net/Articles/604515/ + - Architecture-specific requirements for system calls are discussed in the - syscall(2) man-page: + :manpage:`syscall(2)` man-page: http://man7.org/linux/man-pages/man2/syscall.2.html#NOTES - - Collated emails from Linus Torvalds discussing the problems with ioctl(): + - Collated emails from Linus Torvalds discussing the problems with ``ioctl()``: http://yarchive.net/comp/linux/ioctl.html - "How to not invent kernel interfaces", Arnd Bergmann, http://www.ukuug.org/events/linux2007/2007/papers/Bergmann.pdf @@ -507,17 +520,19 @@ References and Sources commit: https://lkml.org/lkml/2014/11/19/254 - Suggestion from Greg Kroah-Hartman that it's good for new system calls to come with a man-page & selftest: https://lkml.org/lkml/2014/3/19/710 - - Discussion from Michael Kerrisk of new system call vs. prctl(2) extension: + - Discussion from Michael Kerrisk of new system call vs. :manpage:`prctl(2)` extension: https://lkml.org/lkml/2014/6/3/411 - Suggestion from Ingo Molnar that system calls that involve multiple arguments should encapsulate those arguments in a struct, which includes a size field for future extensibility: https://lkml.org/lkml/2015/7/30/117 - Numbering oddities arising from (re-)use of O_* numbering space flags: + - commit 75069f2b5bfb ("vfs: renumber FMODE_NONOTIFY and add to uniqueness check") - commit 12ed2e36c98a ("fanotify: FMODE_NONOTIFY and __O_SYNC in sparc conflict") - commit bb458c644a59 ("Safer ABI for O_TMPFILE") + - Discussion from Matthew Wilcox about restrictions on 64-bit arguments: https://lkml.org/lkml/2008/12/12/187 - Recommendation from Greg Kroah-Hartman that unknown flags should be diff --git a/Documentation/applying-patches.txt b/Documentation/process/applying-patches.rst index 02ce492..abd7dc7 100644 --- a/Documentation/applying-patches.txt +++ b/Documentation/process/applying-patches.rst @@ -427,7 +427,7 @@ The -mm patches are experimental patches released by Andrew Morton. In the past, -mm tree were used to also test subsystem patches, but this function is now done via the -:ref:`linux-next <https://www.kernel.org/doc/man-pages/linux-next.html>` +`linux-next <https://www.kernel.org/doc/man-pages/linux-next.html>` tree. The Subsystem maintainers push their patches first to linux-next, and, during the merge window, sends them directly to Linus. @@ -462,4 +462,3 @@ the kernel. Thank you's to Randy Dunlap, Rolf Eike Beer, Linus Torvalds, Bodo Eggert, Johannes Stezenbach, Grant Coady, Pavel Machek and others that I may have forgotten for their reviews and contributions to this document. - diff --git a/Documentation/Changes b/Documentation/process/changes.rst index 22797a1..22797a1 100644 --- a/Documentation/Changes +++ b/Documentation/process/changes.rst diff --git a/Documentation/CodeOfConflict b/Documentation/process/code-of-conflict.rst index 49a8ecc..47b6de76 100644 --- a/Documentation/CodeOfConflict +++ b/Documentation/process/code-of-conflict.rst @@ -19,7 +19,8 @@ please contact the Linux Foundation's Technical Advisory Board at will work to resolve the issue to the best of their ability. For more information on who is on the Technical Advisory Board and what their role is, please see: - http://www.linuxfoundation.org/projects/linux/tab + + - http://www.linuxfoundation.org/projects/linux/tab As a reviewer of code, please strive to keep things civil and focused on the technical issues involved. We are all humans, and frustrations can diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst new file mode 100644 index 0000000..968808be --- /dev/null +++ b/Documentation/process/coding-style.rst @@ -0,0 +1,1062 @@ +.. _codingstyle: + +Linux kernel coding style +========================= + +This is a short document describing the preferred coding style for the +linux kernel. Coding style is very personal, and I won't **force** my +views on anybody, but this is what goes for anything that I have to be +able to maintain, and I'd prefer it for most other things too. Please +at least consider the points made here. + +First off, I'd suggest printing out a copy of the GNU coding standards, +and NOT read it. Burn them, it's a great symbolic gesture. + +Anyway, here goes: + + +1) Indentation +-------------- + +Tabs are 8 characters, and thus indentations are also 8 characters. +There are heretic movements that try to make indentations 4 (or even 2!) +characters deep, and that is akin to trying to define the value of PI to +be 3. + +Rationale: The whole idea behind indentation is to clearly define where +a block of control starts and ends. Especially when you've been looking +at your screen for 20 straight hours, you'll find it a lot easier to see +how the indentation works if you have large indentations. + +Now, some people will claim that having 8-character indentations makes +the code move too far to the right, and makes it hard to read on a +80-character terminal screen. The answer to that is that if you need +more than 3 levels of indentation, you're screwed anyway, and should fix +your program. + +In short, 8-char indents make things easier to read, and have the added +benefit of warning you when you're nesting your functions too deep. +Heed that warning. + +The preferred way to ease multiple indentation levels in a switch statement is +to align the ``switch`` and its subordinate ``case`` labels in the same column +instead of ``double-indenting`` the ``case`` labels. E.g.: + +.. code-block:: c + + switch (suffix) { + case 'G': + case 'g': + mem <<= 30; + break; + case 'M': + case 'm': + mem <<= 20; + break; + case 'K': + case 'k': + mem <<= 10; + /* fall through */ + default: + break; + } + +Don't put multiple statements on a single line unless you have +something to hide: + +.. code-block:: c + + if (condition) do_this; + do_something_everytime; + +Don't put multiple assignments on a single line either. Kernel coding style +is super simple. Avoid tricky expressions. + +Outside of comments, documentation and except in Kconfig, spaces are never +used for indentation, and the above example is deliberately broken. + +Get a decent editor and don't leave whitespace at the end of lines. + + +2) Breaking long lines and strings +---------------------------------- + +Coding style is all about readability and maintainability using commonly +available tools. + +The limit on the length of lines is 80 columns and this is a strongly +preferred limit. + +Statements longer than 80 columns will be broken into sensible chunks, unless +exceeding 80 columns significantly increases readability and does not hide +information. Descendants are always substantially shorter than the parent and +are placed substantially to the right. The same applies to function headers +with a long argument list. However, never break user-visible strings such as +printk messages, because that breaks the ability to grep for them. + + +3) Placing Braces and Spaces +---------------------------- + +The other issue that always comes up in C styling is the placement of +braces. Unlike the indent size, there are few technical reasons to +choose one placement strategy over the other, but the preferred way, as +shown to us by the prophets Kernighan and Ritchie, is to put the opening +brace last on the line, and put the closing brace first, thusly: + +.. code-block:: c + + if (x is true) { + we do y + } + +This applies to all non-function statement blocks (if, switch, for, +while, do). E.g.: + +.. code-block:: c + + switch (action) { + case KOBJ_ADD: + return "add"; + case KOBJ_REMOVE: + return "remove"; + case KOBJ_CHANGE: + return "change"; + default: + return NULL; + } + +However, there is one special case, namely functions: they have the +opening brace at the beginning of the next line, thus: + +.. code-block:: c + + int function(int x) + { + body of function + } + +Heretic people all over the world have claimed that this inconsistency +is ... well ... inconsistent, but all right-thinking people know that +(a) K&R are **right** and (b) K&R are right. Besides, functions are +special anyway (you can't nest them in C). + +Note that the closing brace is empty on a line of its own, **except** in +the cases where it is followed by a continuation of the same statement, +ie a ``while`` in a do-statement or an ``else`` in an if-statement, like +this: + +.. code-block:: c + + do { + body of do-loop + } while (condition); + +and + +.. code-block:: c + + if (x == y) { + .. + } else if (x > y) { + ... + } else { + .... + } + +Rationale: K&R. + +Also, note that this brace-placement also minimizes the number of empty +(or almost empty) lines, without any loss of readability. Thus, as the +supply of new-lines on your screen is not a renewable resource (think +25-line terminal screens here), you have more empty lines to put +comments on. + +Do not unnecessarily use braces where a single statement will do. + +.. code-block:: c + + if (condition) + action(); + +and + +.. code-block:: none + + if (condition) + do_this(); + else + do_that(); + +This does not apply if only one branch of a conditional statement is a single +statement; in the latter case use braces in both branches: + +.. code-block:: c + + if (condition) { + do_this(); + do_that(); + } else { + otherwise(); + } + +3.1) Spaces +*********** + +Linux kernel style for use of spaces depends (mostly) on +function-versus-keyword usage. Use a space after (most) keywords. The +notable exceptions are sizeof, typeof, alignof, and __attribute__, which look +somewhat like functions (and are usually used with parentheses in Linux, +although they are not required in the language, as in: ``sizeof info`` after +``struct fileinfo info;`` is declared). + +So use a space after these keywords:: + + if, switch, case, for, do, while + +but not with sizeof, typeof, alignof, or __attribute__. E.g., + +.. code-block:: c + + + s = sizeof(struct file); + +Do not add spaces around (inside) parenthesized expressions. This example is +**bad**: + +.. code-block:: c + + + s = sizeof( struct file ); + +When declaring pointer data or a function that returns a pointer type, the +preferred use of ``*`` is adjacent to the data name or function name and not +adjacent to the type name. Examples: + +.. code-block:: c + + + char *linux_banner; + unsigned long long memparse(char *ptr, char **retptr); + char *match_strdup(substring_t *s); + +Use one space around (on each side of) most binary and ternary operators, +such as any of these:: + + = + - < > * / % | & ^ <= >= == != ? : + +but no space after unary operators:: + + & * + - ~ ! sizeof typeof alignof __attribute__ defined + +no space before the postfix increment & decrement unary operators:: + + ++ -- + +no space after the prefix increment & decrement unary operators:: + + ++ -- + +and no space around the ``.`` and ``->`` structure member operators. + +Do not leave trailing whitespace at the ends of lines. Some editors with +``smart`` indentation will insert whitespace at the beginning of new lines as +appropriate, so you can start typing the next line of code right away. +However, some such editors do not remove the whitespace if you end up not +putting a line of code there, such as if you leave a blank line. As a result, +you end up with lines containing trailing whitespace. + +Git will warn you about patches that introduce trailing whitespace, and can +optionally strip the trailing whitespace for you; however, if applying a series +of patches, this may make later patches in the series fail by changing their +context lines. + + +4) Naming +--------- + +C is a Spartan language, and so should your naming be. Unlike Modula-2 +and Pascal programmers, C programmers do not use cute names like +ThisVariableIsATemporaryCounter. A C programmer would call that +variable ``tmp``, which is much easier to write, and not the least more +difficult to understand. + +HOWEVER, while mixed-case names are frowned upon, descriptive names for +global variables are a must. To call a global function ``foo`` is a +shooting offense. + +GLOBAL variables (to be used only if you **really** need them) need to +have descriptive names, as do global functions. If you have a function +that counts the number of active users, you should call that +``count_active_users()`` or similar, you should **not** call it ``cntusr()``. + +Encoding the type of a function into the name (so-called Hungarian +notation) is brain damaged - the compiler knows the types anyway and can +check those, and it only confuses the programmer. No wonder MicroSoft +makes buggy programs. + +LOCAL variable names should be short, and to the point. If you have +some random integer loop counter, it should probably be called ``i``. +Calling it ``loop_counter`` is non-productive, if there is no chance of it +being mis-understood. Similarly, ``tmp`` can be just about any type of +variable that is used to hold a temporary value. + +If you are afraid to mix up your local variable names, you have another +problem, which is called the function-growth-hormone-imbalance syndrome. +See chapter 6 (Functions). + + +5) Typedefs +----------- + +Please don't use things like ``vps_t``. +It's a **mistake** to use typedef for structures and pointers. When you see a + +.. code-block:: c + + + vps_t a; + +in the source, what does it mean? +In contrast, if it says + +.. code-block:: c + + struct virtual_container *a; + +you can actually tell what ``a`` is. + +Lots of people think that typedefs ``help readability``. Not so. They are +useful only for: + + (a) totally opaque objects (where the typedef is actively used to **hide** + what the object is). + + Example: ``pte_t`` etc. opaque objects that you can only access using + the proper accessor functions. + + .. note:: + + Opaqueness and ``accessor functions`` are not good in themselves. + The reason we have them for things like pte_t etc. is that there + really is absolutely **zero** portably accessible information there. + + (b) Clear integer types, where the abstraction **helps** avoid confusion + whether it is ``int`` or ``long``. + + u8/u16/u32 are perfectly fine typedefs, although they fit into + category (d) better than here. + + .. note:: + + Again - there needs to be a **reason** for this. If something is + ``unsigned long``, then there's no reason to do + + typedef unsigned long myflags_t; + + but if there is a clear reason for why it under certain circumstances + might be an ``unsigned int`` and under other configurations might be + ``unsigned long``, then by all means go ahead and use a typedef. + + (c) when you use sparse to literally create a **new** type for + type-checking. + + (d) New types which are identical to standard C99 types, in certain + exceptional circumstances. + + Although it would only take a short amount of time for the eyes and + brain to become accustomed to the standard types like ``uint32_t``, + some people object to their use anyway. + + Therefore, the Linux-specific ``u8/u16/u32/u64`` types and their + signed equivalents which are identical to standard types are + permitted -- although they are not mandatory in new code of your + own. + + When editing existing code which already uses one or the other set + of types, you should conform to the existing choices in that code. + + (e) Types safe for use in userspace. + + In certain structures which are visible to userspace, we cannot + require C99 types and cannot use the ``u32`` form above. Thus, we + use __u32 and similar types in all structures which are shared + with userspace. + +Maybe there are other cases too, but the rule should basically be to NEVER +EVER use a typedef unless you can clearly match one of those rules. + +In general, a pointer, or a struct that has elements that can reasonably +be directly accessed should **never** be a typedef. + + +6) Functions +------------ + +Functions should be short and sweet, and do just one thing. They should +fit on one or two screenfuls of text (the ISO/ANSI screen size is 80x24, +as we all know), and do one thing and do that well. + +The maximum length of a function is inversely proportional to the +complexity and indentation level of that function. So, if you have a +conceptually simple function that is just one long (but simple) +case-statement, where you have to do lots of small things for a lot of +different cases, it's OK to have a longer function. + +However, if you have a complex function, and you suspect that a +less-than-gifted first-year high-school student might not even +understand what the function is all about, you should adhere to the +maximum limits all the more closely. Use helper functions with +descriptive names (you can ask the compiler to in-line them if you think +it's performance-critical, and it will probably do a better job of it +than you would have done). + +Another measure of the function is the number of local variables. They +shouldn't exceed 5-10, or you're doing something wrong. Re-think the +function, and split it into smaller pieces. A human brain can +generally easily keep track of about 7 different things, anything more +and it gets confused. You know you're brilliant, but maybe you'd like +to understand what you did 2 weeks from now. + +In source files, separate functions with one blank line. If the function is +exported, the **EXPORT** macro for it should follow immediately after the +closing function brace line. E.g.: + +.. code-block:: c + + int system_is_up(void) + { + return system_state == SYSTEM_RUNNING; + } + EXPORT_SYMBOL(system_is_up); + +In function prototypes, include parameter names with their data types. +Although this is not required by the C language, it is preferred in Linux +because it is a simple way to add valuable information for the reader. + + +7) Centralized exiting of functions +----------------------------------- + +Albeit deprecated by some people, the equivalent of the goto statement is +used frequently by compilers in form of the unconditional jump instruction. + +The goto statement comes in handy when a function exits from multiple +locations and some common work such as cleanup has to be done. If there is no +cleanup needed then just return directly. + +Choose label names which say what the goto does or why the goto exists. An +example of a good name could be ``out_free_buffer:`` if the goto frees ``buffer``. +Avoid using GW-BASIC names like ``err1:`` and ``err2:``, as you would have to +renumber them if you ever add or remove exit paths, and they make correctness +difficult to verify anyway. + +The rationale for using gotos is: + +- unconditional statements are easier to understand and follow +- nesting is reduced +- errors by not updating individual exit points when making + modifications are prevented +- saves the compiler work to optimize redundant code away ;) + +.. code-block:: c + + int fun(int a) + { + int result = 0; + char *buffer; + + buffer = kmalloc(SIZE, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + if (condition1) { + while (loop1) { + ... + } + result = 1; + goto out_buffer; + } + ... + out_free_buffer: + kfree(buffer); + return result; + } + +A common type of bug to be aware of is ``one err bugs`` which look like this: + +.. code-block:: c + + err: + kfree(foo->bar); + kfree(foo); + return ret; + +The bug in this code is that on some exit paths ``foo`` is NULL. Normally the +fix for this is to split it up into two error labels ``err_free_bar:`` and +``err_free_foo:``: + +.. code-block:: c + + err_free_bar: + kfree(foo->bar); + err_free_foo: + kfree(foo); + return ret; + +Ideally you should simulate errors to test all exit paths. + + +8) Commenting +------------- + +Comments are good, but there is also a danger of over-commenting. NEVER +try to explain HOW your code works in a comment: it's much better to +write the code so that the **working** is obvious, and it's a waste of +time to explain badly written code. + +Generally, you want your comments to tell WHAT your code does, not HOW. +Also, try to avoid putting comments inside a function body: if the +function is so complex that you need to separately comment parts of it, +you should probably go back to chapter 6 for a while. You can make +small comments to note or warn about something particularly clever (or +ugly), but try to avoid excess. Instead, put the comments at the head +of the function, telling people what it does, and possibly WHY it does +it. + +When commenting the kernel API functions, please use the kernel-doc format. +See the files Documentation/kernel-documentation.rst and scripts/kernel-doc +for details. + +The preferred style for long (multi-line) comments is: + +.. code-block:: c + + /* + * This is the preferred style for multi-line + * comments in the Linux kernel source code. + * Please use it consistently. + * + * Description: A column of asterisks on the left side, + * with beginning and ending almost-blank lines. + */ + +For files in net/ and drivers/net/ the preferred style for long (multi-line) +comments is a little different. + +.. code-block:: c + + /* The preferred comment style for files in net/ and drivers/net + * looks like this. + * + * It is nearly the same as the generally preferred comment style, + * but there is no initial almost-blank line. + */ + +It's also important to comment data, whether they are basic types or derived +types. To this end, use just one data declaration per line (no commas for +multiple data declarations). This leaves you room for a small comment on each +item, explaining its use. + + +9) You've made a mess of it +--------------------------- + +That's OK, we all do. You've probably been told by your long-time Unix +user helper that ``GNU emacs`` automatically formats the C sources for +you, and you've noticed that yes, it does do that, but the defaults it +uses are less than desirable (in fact, they are worse than random +typing - an infinite number of monkeys typing into GNU emacs would never +make a good program). + +So, you can either get rid of GNU emacs, or change it to use saner +values. To do the latter, you can stick the following in your .emacs file: + +.. code-block:: none + + (defun c-lineup-arglist-tabs-only (ignored) + "Line up argument lists by tabs, not spaces" + (let* ((anchor (c-langelem-pos c-syntactic-element)) + (column (c-langelem-2nd-pos c-syntactic-element)) + (offset (- (1+ column) anchor)) + (steps (floor offset c-basic-offset))) + (* (max steps 1) + c-basic-offset))) + + (add-hook 'c-mode-common-hook + (lambda () + ;; Add kernel style + (c-add-style + "linux-tabs-only" + '("linux" (c-offsets-alist + (arglist-cont-nonempty + c-lineup-gcc-asm-reg + c-lineup-arglist-tabs-only)))))) + + (add-hook 'c-mode-hook + (lambda () + (let ((filename (buffer-file-name))) + ;; Enable kernel mode for the appropriate files + (when (and filename + (string-match (expand-file-name "~/src/linux-trees") + filename)) + (setq indent-tabs-mode t) + (setq show-trailing-whitespace t) + (c-set-style "linux-tabs-only"))))) + +This will make emacs go better with the kernel coding style for C +files below ``~/src/linux-trees``. + +But even if you fail in getting emacs to do sane formatting, not +everything is lost: use ``indent``. + +Now, again, GNU indent has the same brain-dead settings that GNU emacs +has, which is why you need to give it a few command line options. +However, that's not too bad, because even the makers of GNU indent +recognize the authority of K&R (the GNU people aren't evil, they are +just severely misguided in this matter), so you just give indent the +options ``-kr -i8`` (stands for ``K&R, 8 character indents``), or use +``scripts/Lindent``, which indents in the latest style. + +``indent`` has a lot of options, and especially when it comes to comment +re-formatting you may want to take a look at the man page. But +remember: ``indent`` is not a fix for bad programming. + + +10) Kconfig configuration files +------------------------------- + +For all of the Kconfig* configuration files throughout the source tree, +the indentation is somewhat different. Lines under a ``config`` definition +are indented with one tab, while help text is indented an additional two +spaces. Example:: + + config AUDIT + bool "Auditing support" + depends on NET + help + Enable auditing infrastructure that can be used with another + kernel subsystem, such as SELinux (which requires this for + logging of avc messages output). Does not do system-call + auditing without CONFIG_AUDITSYSCALL. + +Seriously dangerous features (such as write support for certain +filesystems) should advertise this prominently in their prompt string:: + + config ADFS_FS_RW + bool "ADFS write support (DANGEROUS)" + depends on ADFS_FS + ... + +For full documentation on the configuration files, see the file +Documentation/kbuild/kconfig-language.txt. + + +11) Data structures +------------------- + +Data structures that have visibility outside the single-threaded +environment they are created and destroyed in should always have +reference counts. In the kernel, garbage collection doesn't exist (and +outside the kernel garbage collection is slow and inefficient), which +means that you absolutely **have** to reference count all your uses. + +Reference counting means that you can avoid locking, and allows multiple +users to have access to the data structure in parallel - and not having +to worry about the structure suddenly going away from under them just +because they slept or did something else for a while. + +Note that locking is **not** a replacement for reference counting. +Locking is used to keep data structures coherent, while reference +counting is a memory management technique. Usually both are needed, and +they are not to be confused with each other. + +Many data structures can indeed have two levels of reference counting, +when there are users of different ``classes``. The subclass count counts +the number of subclass users, and decrements the global count just once +when the subclass count goes to zero. + +Examples of this kind of ``multi-level-reference-counting`` can be found in +memory management (``struct mm_struct``: mm_users and mm_count), and in +filesystem code (``struct super_block``: s_count and s_active). + +Remember: if another thread can find your data structure, and you don't +have a reference count on it, you almost certainly have a bug. + + +12) Macros, Enums and RTL +------------------------- + +Names of macros defining constants and labels in enums are capitalized. + +.. code-block:: c + + #define CONSTANT 0x12345 + +Enums are preferred when defining several related constants. + +CAPITALIZED macro names are appreciated but macros resembling functions +may be named in lower case. + +Generally, inline functions are preferable to macros resembling functions. + +Macros with multiple statements should be enclosed in a do - while block: + +.. code-block:: c + + #define macrofun(a, b, c) \ + do { \ + if (a == 5) \ + do_this(b, c); \ + } while (0) + +Things to avoid when using macros: + +1) macros that affect control flow: + +.. code-block:: c + + #define FOO(x) \ + do { \ + if (blah(x) < 0) \ + return -EBUGGERED; \ + } while (0) + +is a **very** bad idea. It looks like a function call but exits the ``calling`` +function; don't break the internal parsers of those who will read the code. + +2) macros that depend on having a local variable with a magic name: + +.. code-block:: c + + #define FOO(val) bar(index, val) + +might look like a good thing, but it's confusing as hell when one reads the +code and it's prone to breakage from seemingly innocent changes. + +3) macros with arguments that are used as l-values: FOO(x) = y; will +bite you if somebody e.g. turns FOO into an inline function. + +4) forgetting about precedence: macros defining constants using expressions +must enclose the expression in parentheses. Beware of similar issues with +macros using parameters. + +.. code-block:: c + + #define CONSTANT 0x4000 + #define CONSTEXP (CONSTANT | 3) + +5) namespace collisions when defining local variables in macros resembling +functions: + +.. code-block:: c + + #define FOO(x) \ + ({ \ + typeof(x) ret; \ + ret = calc_ret(x); \ + (ret); \ + }) + +ret is a common name for a local variable - __foo_ret is less likely +to collide with an existing variable. + +The cpp manual deals with macros exhaustively. The gcc internals manual also +covers RTL which is used frequently with assembly language in the kernel. + + +13) Printing kernel messages +---------------------------- + +Kernel developers like to be seen as literate. Do mind the spelling +of kernel messages to make a good impression. Do not use crippled +words like ``dont``; use ``do not`` or ``don't`` instead. Make the messages +concise, clear, and unambiguous. + +Kernel messages do not have to be terminated with a period. + +Printing numbers in parentheses (%d) adds no value and should be avoided. + +There are a number of driver model diagnostic macros in <linux/device.h> +which you should use to make sure messages are matched to the right device +and driver, and are tagged with the right level: dev_err(), dev_warn(), +dev_info(), and so forth. For messages that aren't associated with a +particular device, <linux/printk.h> defines pr_notice(), pr_info(), +pr_warn(), pr_err(), etc. + +Coming up with good debugging messages can be quite a challenge; and once +you have them, they can be a huge help for remote troubleshooting. However +debug message printing is handled differently than printing other non-debug +messages. While the other pr_XXX() functions print unconditionally, +pr_debug() does not; it is compiled out by default, unless either DEBUG is +defined or CONFIG_DYNAMIC_DEBUG is set. That is true for dev_dbg() also, +and a related convention uses VERBOSE_DEBUG to add dev_vdbg() messages to +the ones already enabled by DEBUG. + +Many subsystems have Kconfig debug options to turn on -DDEBUG in the +corresponding Makefile; in other cases specific files #define DEBUG. And +when a debug message should be unconditionally printed, such as if it is +already inside a debug-related #ifdef section, printk(KERN_DEBUG ...) can be +used. + + +14) Allocating memory +--------------------- + +The kernel provides the following general purpose memory allocators: +kmalloc(), kzalloc(), kmalloc_array(), kcalloc(), vmalloc(), and +vzalloc(). Please refer to the API documentation for further information +about them. + +The preferred form for passing a size of a struct is the following: + +.. code-block:: c + + p = kmalloc(sizeof(*p), ...); + +The alternative form where struct name is spelled out hurts readability and +introduces an opportunity for a bug when the pointer variable type is changed +but the corresponding sizeof that is passed to a memory allocator is not. + +Casting the return value which is a void pointer is redundant. The conversion +from void pointer to any other pointer type is guaranteed by the C programming +language. + +The preferred form for allocating an array is the following: + +.. code-block:: c + + p = kmalloc_array(n, sizeof(...), ...); + +The preferred form for allocating a zeroed array is the following: + +.. code-block:: c + + p = kcalloc(n, sizeof(...), ...); + +Both forms check for overflow on the allocation size n * sizeof(...), +and return NULL if that occurred. + + +15) The inline disease +---------------------- + +There appears to be a common misperception that gcc has a magic "make me +faster" speedup option called ``inline``. While the use of inlines can be +appropriate (for example as a means of replacing macros, see Chapter 12), it +very often is not. Abundant use of the inline keyword leads to a much bigger +kernel, which in turn slows the system as a whole down, due to a bigger +icache footprint for the CPU and simply because there is less memory +available for the pagecache. Just think about it; a pagecache miss causes a +disk seek, which easily takes 5 milliseconds. There are a LOT of cpu cycles +that can go into these 5 milliseconds. + +A reasonable rule of thumb is to not put inline at functions that have more +than 3 lines of code in them. An exception to this rule are the cases where +a parameter is known to be a compiletime constant, and as a result of this +constantness you *know* the compiler will be able to optimize most of your +function away at compile time. For a good example of this later case, see +the kmalloc() inline function. + +Often people argue that adding inline to functions that are static and used +only once is always a win since there is no space tradeoff. While this is +technically correct, gcc is capable of inlining these automatically without +help, and the maintenance issue of removing the inline when a second user +appears outweighs the potential value of the hint that tells gcc to do +something it would have done anyway. + + +16) Function return values and names +------------------------------------ + +Functions can return values of many different kinds, and one of the +most common is a value indicating whether the function succeeded or +failed. Such a value can be represented as an error-code integer +(-Exxx = failure, 0 = success) or a ``succeeded`` boolean (0 = failure, +non-zero = success). + +Mixing up these two sorts of representations is a fertile source of +difficult-to-find bugs. If the C language included a strong distinction +between integers and booleans then the compiler would find these mistakes +for us... but it doesn't. To help prevent such bugs, always follow this +convention:: + + If the name of a function is an action or an imperative command, + the function should return an error-code integer. If the name + is a predicate, the function should return a "succeeded" boolean. + +For example, ``add work`` is a command, and the add_work() function returns 0 +for success or -EBUSY for failure. In the same way, ``PCI device present`` is +a predicate, and the pci_dev_present() function returns 1 if it succeeds in +finding a matching device or 0 if it doesn't. + +All EXPORTed functions must respect this convention, and so should all +public functions. Private (static) functions need not, but it is +recommended that they do. + +Functions whose return value is the actual result of a computation, rather +than an indication of whether the computation succeeded, are not subject to +this rule. Generally they indicate failure by returning some out-of-range +result. Typical examples would be functions that return pointers; they use +NULL or the ERR_PTR mechanism to report failure. + + +17) Don't re-invent the kernel macros +------------------------------------- + +The header file include/linux/kernel.h contains a number of macros that +you should use, rather than explicitly coding some variant of them yourself. +For example, if you need to calculate the length of an array, take advantage +of the macro + +.. code-block:: c + + #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) + +Similarly, if you need to calculate the size of some structure member, use + +.. code-block:: c + + #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) + +There are also min() and max() macros that do strict type checking if you +need them. Feel free to peruse that header file to see what else is already +defined that you shouldn't reproduce in your code. + + +18) Editor modelines and other cruft +------------------------------------ + +Some editors can interpret configuration information embedded in source files, +indicated with special markers. For example, emacs interprets lines marked +like this: + +.. code-block:: c + + -*- mode: c -*- + +Or like this: + +.. code-block:: c + + /* + Local Variables: + compile-command: "gcc -DMAGIC_DEBUG_FLAG foo.c" + End: + */ + +Vim interprets markers that look like this: + +.. code-block:: c + + /* vim:set sw=8 noet */ + +Do not include any of these in source files. People have their own personal +editor configurations, and your source files should not override them. This +includes markers for indentation and mode configuration. People may use their +own custom mode, or may have some other magic method for making indentation +work correctly. + + +19) Inline assembly +------------------- + +In architecture-specific code, you may need to use inline assembly to interface +with CPU or platform functionality. Don't hesitate to do so when necessary. +However, don't use inline assembly gratuitously when C can do the job. You can +and should poke hardware from C when possible. + +Consider writing simple helper functions that wrap common bits of inline +assembly, rather than repeatedly writing them with slight variations. Remember +that inline assembly can use C parameters. + +Large, non-trivial assembly functions should go in .S files, with corresponding +C prototypes defined in C header files. The C prototypes for assembly +functions should use ``asmlinkage``. + +You may need to mark your asm statement as volatile, to prevent GCC from +removing it if GCC doesn't notice any side effects. You don't always need to +do so, though, and doing so unnecessarily can limit optimization. + +When writing a single inline assembly statement containing multiple +instructions, put each instruction on a separate line in a separate quoted +string, and end each string except the last with \n\t to properly indent the +next instruction in the assembly output: + +.. code-block:: c + + asm ("magic %reg1, #42\n\t" + "more_magic %reg2, %reg3" + : /* outputs */ : /* inputs */ : /* clobbers */); + + +20) Conditional Compilation +--------------------------- + +Wherever possible, don't use preprocessor conditionals (#if, #ifdef) in .c +files; doing so makes code harder to read and logic harder to follow. Instead, +use such conditionals in a header file defining functions for use in those .c +files, providing no-op stub versions in the #else case, and then call those +functions unconditionally from .c files. The compiler will avoid generating +any code for the stub calls, producing identical results, but the logic will +remain easy to follow. + +Prefer to compile out entire functions, rather than portions of functions or +portions of expressions. Rather than putting an ifdef in an expression, factor +out part or all of the expression into a separate helper function and apply the +conditional to that function. + +If you have a function or variable which may potentially go unused in a +particular configuration, and the compiler would warn about its definition +going unused, mark the definition as __maybe_unused rather than wrapping it in +a preprocessor conditional. (However, if a function or variable *always* goes +unused, delete it.) + +Within code, where possible, use the IS_ENABLED macro to convert a Kconfig +symbol into a C boolean expression, and use it in a normal C conditional: + +.. code-block:: c + + if (IS_ENABLED(CONFIG_SOMETHING)) { + ... + } + +The compiler will constant-fold the conditional away, and include or exclude +the block of code just as with an #ifdef, so this will not add any runtime +overhead. However, this approach still allows the C compiler to see the code +inside the block, and check it for correctness (syntax, types, symbol +references, etc). Thus, you still have to use an #ifdef if the code inside the +block references symbols that will not exist if the condition is not met. + +At the end of any non-trivial #if or #ifdef block (more than a few lines), +place a comment after the #endif on the same line, noting the conditional +expression used. For instance: + +.. code-block:: c + + #ifdef CONFIG_SOMETHING + ... + #endif /* CONFIG_SOMETHING */ + + +Appendix I) References +---------------------- + +The C Programming Language, Second Edition +by Brian W. Kernighan and Dennis M. Ritchie. +Prentice Hall, Inc., 1988. +ISBN 0-13-110362-8 (paperback), 0-13-110370-9 (hardback). + +The Practice of Programming +by Brian W. Kernighan and Rob Pike. +Addison-Wesley, Inc., 1999. +ISBN 0-201-61586-X. + +GNU manuals - where in compliance with K&R and this text - for cpp, gcc, +gcc internals and indent, all available from http://www.gnu.org/manual/ + +WG14 is the international standardization working group for the programming +language C, URL: http://www.open-std.org/JTC1/SC22/WG14/ + +Kernel process/coding-style.rst, by greg@kroah.com at OLS 2002: +http://www.kroah.com/linux/talks/ols_2002_kernel_codingstyle_talk/html/ diff --git a/Documentation/development-process/conf.py b/Documentation/process/conf.py index 4b4a12d..1b01a80 100644 --- a/Documentation/development-process/conf.py +++ b/Documentation/process/conf.py @@ -5,6 +5,6 @@ project = 'Linux Kernel Development Documentation' tags.add("subproject") latex_documents = [ - ('index', 'development-process.tex', 'Linux Kernel Development Documentation', + ('index', 'process.tex', 'Linux Kernel Development Documentation', 'The kernel development community', 'manual'), ] diff --git a/Documentation/development-process/development-process.rst b/Documentation/process/development-process.rst index bd1399f..61c627e 100644 --- a/Documentation/development-process/development-process.rst +++ b/Documentation/process/development-process.rst @@ -26,4 +26,3 @@ development (or, indeed, free software development in general). While there is some technical material here, this is very much a process-oriented discussion which does not require a deep knowledge of kernel programming to understand. - diff --git a/Documentation/email-clients.txt b/Documentation/process/email-clients.rst index ac892b3..ac892b3 100644 --- a/Documentation/email-clients.txt +++ b/Documentation/process/email-clients.rst diff --git a/Documentation/HOWTO b/Documentation/process/howto.rst index 5f04234..3f66a19 100644 --- a/Documentation/HOWTO +++ b/Documentation/process/howto.rst @@ -90,19 +90,19 @@ required reading: what is necessary to do to configure and build the kernel. People who are new to the kernel should start here. - :ref:`Documentation/Changes <changes>` + :ref:`Documentation/process/changes.rst <changes>` This file gives a list of the minimum levels of various software packages that are necessary to build and run the kernel successfully. - :ref:`Documentation/CodingStyle <codingstyle>` + :ref:`Documentation/process/coding-style.rst <codingstyle>` This describes the Linux kernel coding style, and some of the rationale behind it. All new code is expected to follow the guidelines in this document. Most maintainers will only accept patches if these rules are followed, and many people will only review code if it is in the proper style. - :ref:`Documentation/SubmittingPatches <submittingpatches>` and :ref:`Documentation/SubmittingDrivers <submittingdrivers>` + :ref:`Documentation/process/submitting-patches.rst <submittingpatches>` and :ref:`Documentation/process/submitting-drivers.rst <submittingdrivers>` These files describe in explicit detail how to successfully create and send a patch, including (but not limited to): @@ -122,7 +122,7 @@ required reading: "Linux kernel patch submission format" http://linux.yyz.us/patch-format.html - :ref:`Documentation/stable_api_nonsense.txt <stable_api_nonsense>` + :ref:`Documentation/process/stable-api-nonsense.rst <stable_api_nonsense>` This file describes the rationale behind the conscious decision to not have a stable API within the kernel, including things like: @@ -135,29 +135,29 @@ required reading: philosophy and is very important for people moving to Linux from development on other Operating Systems. - :ref:`Documentation/SecurityBugs <securitybugs>` + :ref:`Documentation/admin-guide/security-bugs.rst <securitybugs>` If you feel you have found a security problem in the Linux kernel, please follow the steps in this document to help notify the kernel developers, and help solve the issue. - :ref:`Documentation/ManagementStyle <managementstyle>` + :ref:`Documentation/process/management-style.rst <managementstyle>` This document describes how Linux kernel maintainers operate and the shared ethos behind their methodologies. This is important reading for anyone new to kernel development (or anyone simply curious about it), as it resolves a lot of common misconceptions and confusion about the unique behavior of kernel maintainers. - :ref:`Documentation/stable_kernel_rules.txt <stable_kernel_rules>` + :ref:`Documentation/process/stable-kernel-rules.rst <stable_kernel_rules>` This file describes the rules on how the stable kernel releases happen, and what to do if you want to get a change into one of these releases. - :ref:`Documentation/kernel-docs.txt <kernel_docs>` + :ref:`Documentation/process/kernel-docs.rst <kernel_docs>` A list of external documentation that pertains to kernel development. Please consult this list if you do not find what you are looking for within the in-kernel documentation. - :ref:`Documentation/applying-patches.txt <applying_patches>` + :ref:`Documentation/process/applying-patches.rst <applying_patches>` A good introduction describing exactly what a patch is and how to apply it to the different development branches of the kernel. @@ -307,7 +307,7 @@ two weeks, but it can be longer if there are no pressing problems. A security-related problem, instead, can cause a release to happen almost instantly. -The file Documentation/stable_kernel_rules.txt in the kernel tree +The file Documentation/process/stable-kernel-rules.rst in the kernel tree documents what kinds of changes are acceptable for the -stable tree, and how the release process works. @@ -366,7 +366,7 @@ tool. For details on how to use the kernel bugzilla, please see: https://bugzilla.kernel.org/page.cgi?id=faq.html -The file REPORTING-BUGS in the main kernel source directory has a good +The file admin-guide/reporting-bugs.rst in the main kernel source directory has a good template for how to report a possible kernel bug, and details what kind of information is needed by the kernel developers to help track down the problem. @@ -440,7 +440,7 @@ add your statements between the individual quoted sections instead of writing at the top of the mail. If you add patches to your mail, make sure they are plain readable text -as stated in Documentation/SubmittingPatches. +as stated in Documentation/process/submitting-patches.rst. Kernel developers don't want to deal with attachments or compressed patches; they may want to comment on individual lines of your patch, which works only that way. Make sure you diff --git a/Documentation/process/index.rst b/Documentation/process/index.rst new file mode 100644 index 0000000..6ee8187 --- /dev/null +++ b/Documentation/process/index.rst @@ -0,0 +1,32 @@ +.. raw:: latex + + \renewcommand\thesection* + \renewcommand\thesubsection* + + +Linux Kernel Development Documentation +====================================== + +Contents: + +.. toctree:: + :maxdepth: 2 + + howto + changes + coding-style + submitting-patches + submitting-drivers + stable-api-nonsense + management-style + stable-kernel-rules + kernel-docs + applying-patches + email-clients + submit-checklist + code-of-conflict + adding-syscalls + magic-number + volatile-considered-harmful + + development-process diff --git a/Documentation/kernel-docs.txt b/Documentation/process/kernel-docs.rst index 05a7857..05a7857 100644 --- a/Documentation/kernel-docs.txt +++ b/Documentation/process/kernel-docs.rst diff --git a/Documentation/process/magic-number.rst b/Documentation/process/magic-number.rst new file mode 100644 index 0000000..c74199f --- /dev/null +++ b/Documentation/process/magic-number.rst @@ -0,0 +1,164 @@ +Linux magic numbers +=================== + +This file is a registry of magic numbers which are in use. When you +add a magic number to a structure, you should also add it to this +file, since it is best if the magic numbers used by various structures +are unique. + +It is a **very** good idea to protect kernel data structures with magic +numbers. This allows you to check at run time whether (a) a structure +has been clobbered, or (b) you've passed the wrong structure to a +routine. This last is especially useful --- particularly when you are +passing pointers to structures via a void * pointer. The tty code, +for example, does this frequently to pass driver-specific and line +discipline-specific structures back and forth. + +The way to use magic numbers is to declare then at the beginning of +the structure, like so:: + + struct tty_ldisc { + int magic; + ... + }; + +Please follow this discipline when you are adding future enhancements +to the kernel! It has saved me countless hours of debugging, +especially in the screwy cases where an array has been overrun and +structures following the array have been overwritten. Using this +discipline, these cases get detected quickly and safely. + +Changelog:: + + Theodore Ts'o + 31 Mar 94 + + The magic table is current to Linux 2.1.55. + + Michael Chastain + <mailto:mec@shout.net> + 22 Sep 1997 + + Now it should be up to date with Linux 2.1.112. Because + we are in feature freeze time it is very unlikely that + something will change before 2.2.x. The entries are + sorted by number field. + + Krzysztof G. Baranowski + <mailto: kgb@knm.org.pl> + 29 Jul 1998 + + Updated the magic table to Linux 2.5.45. Right over the feature freeze, + but it is possible that some new magic numbers will sneak into the + kernel before 2.6.x yet. + + Petr Baudis + <pasky@ucw.cz> + 03 Nov 2002 + + Updated the magic table to Linux 2.5.74. + + Fabian Frederick + <ffrederick@users.sourceforge.net> + 09 Jul 2003 + + +===================== ================ ======================== ========================================== +Magic Name Number Structure File +===================== ================ ======================== ========================================== +PG_MAGIC 'P' pg_{read,write}_hdr ``include/linux/pg.h`` +CMAGIC 0x0111 user ``include/linux/a.out.h`` +MKISS_DRIVER_MAGIC 0x04bf mkiss_channel ``drivers/net/mkiss.h`` +HDLC_MAGIC 0x239e n_hdlc ``drivers/char/n_hdlc.c`` +APM_BIOS_MAGIC 0x4101 apm_user ``arch/x86/kernel/apm_32.c`` +CYCLADES_MAGIC 0x4359 cyclades_port ``include/linux/cyclades.h`` +DB_MAGIC 0x4442 fc_info ``drivers/net/iph5526_novram.c`` +DL_MAGIC 0x444d fc_info ``drivers/net/iph5526_novram.c`` +FASYNC_MAGIC 0x4601 fasync_struct ``include/linux/fs.h`` +FF_MAGIC 0x4646 fc_info ``drivers/net/iph5526_novram.c`` +ISICOM_MAGIC 0x4d54 isi_port ``include/linux/isicom.h`` +PTY_MAGIC 0x5001 ``drivers/char/pty.c`` +PPP_MAGIC 0x5002 ppp ``include/linux/if_pppvar.h`` +SERIAL_MAGIC 0x5301 async_struct ``include/linux/serial.h`` +SSTATE_MAGIC 0x5302 serial_state ``include/linux/serial.h`` +SLIP_MAGIC 0x5302 slip ``drivers/net/slip.h`` +STRIP_MAGIC 0x5303 strip ``drivers/net/strip.c`` +X25_ASY_MAGIC 0x5303 x25_asy ``drivers/net/x25_asy.h`` +SIXPACK_MAGIC 0x5304 sixpack ``drivers/net/hamradio/6pack.h`` +AX25_MAGIC 0x5316 ax_disp ``drivers/net/mkiss.h`` +TTY_MAGIC 0x5401 tty_struct ``include/linux/tty.h`` +MGSL_MAGIC 0x5401 mgsl_info ``drivers/char/synclink.c`` +TTY_DRIVER_MAGIC 0x5402 tty_driver ``include/linux/tty_driver.h`` +MGSLPC_MAGIC 0x5402 mgslpc_info ``drivers/char/pcmcia/synclink_cs.c`` +TTY_LDISC_MAGIC 0x5403 tty_ldisc ``include/linux/tty_ldisc.h`` +USB_SERIAL_MAGIC 0x6702 usb_serial ``drivers/usb/serial/usb-serial.h`` +FULL_DUPLEX_MAGIC 0x6969 ``drivers/net/ethernet/dec/tulip/de2104x.c`` +USB_BLUETOOTH_MAGIC 0x6d02 usb_bluetooth ``drivers/usb/class/bluetty.c`` +RFCOMM_TTY_MAGIC 0x6d02 ``net/bluetooth/rfcomm/tty.c`` +USB_SERIAL_PORT_MAGIC 0x7301 usb_serial_port ``drivers/usb/serial/usb-serial.h`` +CG_MAGIC 0x00090255 ufs_cylinder_group ``include/linux/ufs_fs.h`` +RPORT_MAGIC 0x00525001 r_port ``drivers/char/rocket_int.h`` +LSEMAGIC 0x05091998 lse ``drivers/fc4/fc.c`` +GDTIOCTL_MAGIC 0x06030f07 gdth_iowr_str ``drivers/scsi/gdth_ioctl.h`` +RIEBL_MAGIC 0x09051990 ``drivers/net/atarilance.c`` +NBD_REQUEST_MAGIC 0x12560953 nbd_request ``include/linux/nbd.h`` +RED_MAGIC2 0x170fc2a5 (any) ``mm/slab.c`` +BAYCOM_MAGIC 0x19730510 baycom_state ``drivers/net/baycom_epp.c`` +ISDN_X25IFACE_MAGIC 0x1e75a2b9 isdn_x25iface_proto_data ``drivers/isdn/isdn_x25iface.h`` +ECP_MAGIC 0x21504345 cdkecpsig ``include/linux/cdk.h`` +LSOMAGIC 0x27091997 lso ``drivers/fc4/fc.c`` +LSMAGIC 0x2a3b4d2a ls ``drivers/fc4/fc.c`` +WANPIPE_MAGIC 0x414C4453 sdla_{dump,exec} ``include/linux/wanpipe.h`` +CS_CARD_MAGIC 0x43525553 cs_card ``sound/oss/cs46xx.c`` +LABELCL_MAGIC 0x4857434c labelcl_info_s ``include/asm/ia64/sn/labelcl.h`` +ISDN_ASYNC_MAGIC 0x49344C01 modem_info ``include/linux/isdn.h`` +CTC_ASYNC_MAGIC 0x49344C01 ctc_tty_info ``drivers/s390/net/ctctty.c`` +ISDN_NET_MAGIC 0x49344C02 isdn_net_local_s ``drivers/isdn/i4l/isdn_net_lib.h`` +SAVEKMSG_MAGIC2 0x4B4D5347 savekmsg ``arch/*/amiga/config.c`` +CS_STATE_MAGIC 0x4c4f4749 cs_state ``sound/oss/cs46xx.c`` +SLAB_C_MAGIC 0x4f17a36d kmem_cache ``mm/slab.c`` +COW_MAGIC 0x4f4f4f4d cow_header_v1 ``arch/um/drivers/ubd_user.c`` +I810_CARD_MAGIC 0x5072696E i810_card ``sound/oss/i810_audio.c`` +TRIDENT_CARD_MAGIC 0x5072696E trident_card ``sound/oss/trident.c`` +ROUTER_MAGIC 0x524d4157 wan_device [in ``wanrouter.h`` pre 3.9] +SAVEKMSG_MAGIC1 0x53415645 savekmsg ``arch/*/amiga/config.c`` +GDA_MAGIC 0x58464552 gda ``arch/mips/include/asm/sn/gda.h`` +RED_MAGIC1 0x5a2cf071 (any) ``mm/slab.c`` +EEPROM_MAGIC_VALUE 0x5ab478d2 lanai_dev ``drivers/atm/lanai.c`` +HDLCDRV_MAGIC 0x5ac6e778 hdlcdrv_state ``include/linux/hdlcdrv.h`` +PCXX_MAGIC 0x5c6df104 channel ``drivers/char/pcxx.h`` +KV_MAGIC 0x5f4b565f kernel_vars_s ``arch/mips/include/asm/sn/klkernvars.h`` +I810_STATE_MAGIC 0x63657373 i810_state ``sound/oss/i810_audio.c`` +TRIDENT_STATE_MAGIC 0x63657373 trient_state ``sound/oss/trident.c`` +M3_CARD_MAGIC 0x646e6f50 m3_card ``sound/oss/maestro3.c`` +FW_HEADER_MAGIC 0x65726F66 fw_header ``drivers/atm/fore200e.h`` +SLOT_MAGIC 0x67267321 slot ``drivers/hotplug/cpqphp.h`` +SLOT_MAGIC 0x67267322 slot ``drivers/hotplug/acpiphp.h`` +LO_MAGIC 0x68797548 nbd_device ``include/linux/nbd.h`` +OPROFILE_MAGIC 0x6f70726f super_block ``drivers/oprofile/oprofilefs.h`` +M3_STATE_MAGIC 0x734d724d m3_state ``sound/oss/maestro3.c`` +VMALLOC_MAGIC 0x87654320 snd_alloc_track ``sound/core/memory.c`` +KMALLOC_MAGIC 0x87654321 snd_alloc_track ``sound/core/memory.c`` +PWC_MAGIC 0x89DC10AB pwc_device ``drivers/usb/media/pwc.h`` +NBD_REPLY_MAGIC 0x96744668 nbd_reply ``include/linux/nbd.h`` +ENI155_MAGIC 0xa54b872d midway_eprom ``drivers/atm/eni.h`` +CODA_MAGIC 0xC0DAC0DA coda_file_info ``fs/coda/coda_fs_i.h`` +DPMEM_MAGIC 0xc0ffee11 gdt_pci_sram ``drivers/scsi/gdth.h`` +YAM_MAGIC 0xF10A7654 yam_port ``drivers/net/hamradio/yam.c`` +CCB_MAGIC 0xf2691ad2 ccb ``drivers/scsi/ncr53c8xx.c`` +QUEUE_MAGIC_FREE 0xf7e1c9a3 queue_entry ``drivers/scsi/arm/queue.c`` +QUEUE_MAGIC_USED 0xf7e1cc33 queue_entry ``drivers/scsi/arm/queue.c`` +HTB_CMAGIC 0xFEFAFEF1 htb_class ``net/sched/sch_htb.c`` +NMI_MAGIC 0x48414d4d455201 nmi_s ``arch/mips/include/asm/sn/nmi.h`` +===================== ================ ======================== ========================================== + +Note that there are also defined special per-driver magic numbers in sound +memory management. See ``include/sound/sndmagic.h`` for complete list of them. Many +OSS sound drivers have their magic numbers constructed from the soundcard PCI +ID - these are not listed here as well. + +IrDA subsystem also uses large number of own magic numbers, see +``include/net/irda/irda.h`` for a complete list of them. + +HFS is another larger user of magic numbers - you can find them in +``fs/hfs/hfs.h``. diff --git a/Documentation/ManagementStyle b/Documentation/process/management-style.rst index dea2e66c..45595fd 100644 --- a/Documentation/ManagementStyle +++ b/Documentation/process/management-style.rst @@ -5,7 +5,7 @@ Linux kernel management style This is a short document describing the preferred (or made up, depending on who you ask) management style for the linux kernel. It's meant to -mirror the CodingStyle document to some degree, and mainly written to +mirror the process/coding-style.rst document to some degree, and mainly written to avoid answering [#f1]_ the same (or similar) questions over and over again. Management style is very personal and much harder to quantify than diff --git a/Documentation/stable_api_nonsense.txt b/Documentation/process/stable-api-nonsense.rst index 24f5aee..24f5aee 100644 --- a/Documentation/stable_api_nonsense.txt +++ b/Documentation/process/stable-api-nonsense.rst diff --git a/Documentation/stable_kernel_rules.txt b/Documentation/process/stable-kernel-rules.rst index 4d82e31..11ec2d9 100644 --- a/Documentation/stable_kernel_rules.txt +++ b/Documentation/process/stable-kernel-rules.rst @@ -27,7 +27,7 @@ Rules on what kind of patches are accepted, and which ones are not, into the - It cannot contain any "trivial" fixes in it (spelling changes, whitespace cleanups, etc). - It must follow the - :ref:`Documentation/SubmittingPatches <submittingpatches>` + :ref:`Documentation/process/submitting-patches.rst <submittingpatches>` rules. - It or an equivalent fix must already exist in Linus' tree (upstream). @@ -40,7 +40,7 @@ Procedure for submitting patches to the -stable tree Documentation/networking/netdev-FAQ.txt - Security patches should not be handled (solely) by the -stable review process but should follow the procedures in - :ref:`Documentation/SecurityBugs <securitybugs>`. + :ref:`Documentation/admin-guide/security-bugs.rst <securitybugs>`. For all other submissions, choose one of the following procedures ----------------------------------------------------------------- diff --git a/Documentation/SubmitChecklist b/Documentation/process/submit-checklist.rst index 894289b..a0d9d34 100644 --- a/Documentation/SubmitChecklist +++ b/Documentation/process/submit-checklist.rst @@ -7,7 +7,7 @@ Here are some basic things that developers should do if they want to see their kernel patch submissions accepted more quickly. These are all above and beyond the documentation that is provided in -:ref:`Documentation/SubmittingPatches <submittingpatches>` +:ref:`Documentation/process/submitting-patches.rst <submittingpatches>` and elsewhere regarding submitting Linux kernel patches. @@ -31,7 +31,7 @@ and elsewhere regarding submitting Linux kernel patches. tends to use ``unsigned long`` for 64-bit quantities. 5) Check your patch for general style as detailed in - :ref:`Documentation/CodingStyle <codingstyle>`. + :ref:`Documentation/process/coding-style.rst <codingstyle>`. Check for trivial violations with the patch style checker prior to submission (``scripts/checkpatch.pl``). You should be able to justify all violations that remain in @@ -78,7 +78,7 @@ and elsewhere regarding submitting Linux kernel patches. 16) All new ``/proc`` entries are documented under ``Documentation/`` 17) All new kernel boot parameters are documented in - ``Documentation/kernel-parameters.txt``. + ``Documentation/admin-guide/kernel-parameters.rst``. 18) All new module parameters are documented with ``MODULE_PARM_DESC()`` diff --git a/Documentation/SubmittingDrivers b/Documentation/process/submitting-drivers.rst index 252b77a..0939d01 100644 --- a/Documentation/SubmittingDrivers +++ b/Documentation/process/submitting-drivers.rst @@ -8,7 +8,7 @@ various kernel trees. Note that if you are interested in video card drivers you should probably talk to XFree86 (http://www.xfree86.org/) and/or X.Org (http://x.org/) instead. -Also read the Documentation/SubmittingPatches document. +Also read the Documentation/process/submitting-patches.rst document. Allocating Device Numbers @@ -19,7 +19,7 @@ by the Linux assigned name and number authority (currently this is Torben Mathiasen). The site is http://www.lanana.org/. This also deals with allocating numbers for devices that are not going to be submitted to the mainstream kernel. -See Documentation/devices.txt for more information on this. +See Documentation/admin-guide/devices.rst for more information on this. If you don't use assigned numbers then when your device is submitted it will be given an assigned number even if that is different from values you may @@ -73,7 +73,7 @@ Interfaces: Code: Please use the Linux style of code formatting as documented - in :ref:`Documentation/CodingStyle <codingStyle>`. + in :ref:`Documentation/process/coding-style.rst <codingStyle>`. If you have sections of code that need to be in other formats, for example because they are shared with a windows driver kit and you want to @@ -109,7 +109,7 @@ PM support: anything. For the driver testing instructions see Documentation/power/drivers-testing.txt and for a relatively complete overview of the power management issues related to - drivers see Documentation/power/devices.txt . + drivers see Documentation/power/admin-guide/devices.rst . Control: In general if there is active maintenance of a driver by diff --git a/Documentation/process/submitting-patches.rst b/Documentation/process/submitting-patches.rst new file mode 100644 index 0000000..b4cf8f3 --- /dev/null +++ b/Documentation/process/submitting-patches.rst @@ -0,0 +1,840 @@ +.. _submittingpatches: + +How to Get Your Change Into the Linux Kernel or Care And Operation Of Your Linus Torvalds +========================================================================================= + +For a person or company who wishes to submit a change to the Linux +kernel, the process can sometimes be daunting if you're not familiar +with "the system." This text is a collection of suggestions which +can greatly increase the chances of your change being accepted. + +This document contains a large number of suggestions in a relatively terse +format. For detailed information on how the kernel development process +works, see :ref:`Documentation/process <development_process_main>`. +Also, read :ref:`Documentation/process/submit-checklist.rst <submitchecklist>` +for a list of items to check before +submitting code. If you are submitting a driver, also read +:ref:`Documentation/process/submitting-drivers.rst <submittingdrivers>`; +for device tree binding patches, read +Documentation/devicetree/bindings/submitting-patches.txt. + +Many of these steps describe the default behavior of the ``git`` version +control system; if you use ``git`` to prepare your patches, you'll find much +of the mechanical work done for you, though you'll still need to prepare +and document a sensible set of patches. In general, use of ``git`` will make +your life as a kernel developer easier. + +Creating and Sending your Change +******************************** + + +0) Obtain a current source tree +------------------------------- + +If you do not have a repository with the current kernel source handy, use +``git`` to obtain one. You'll want to start with the mainline repository, +which can be grabbed with:: + + git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git + +Note, however, that you may not want to develop against the mainline tree +directly. Most subsystem maintainers run their own trees and want to see +patches prepared against those trees. See the **T:** entry for the subsystem +in the MAINTAINERS file to find that tree, or simply ask the maintainer if +the tree is not listed there. + +It is still possible to download kernel releases via tarballs (as described +in the next section), but that is the hard way to do kernel development. + +1) ``diff -up`` +--------------- + +If you must generate your patches by hand, use ``diff -up`` or ``diff -uprN`` +to create patches. Git generates patches in this form by default; if +you're using ``git``, you can skip this section entirely. + +All changes to the Linux kernel occur in the form of patches, as +generated by :manpage:`diff(1)`. When creating your patch, make sure to +create it in "unified diff" format, as supplied by the ``-u`` argument +to :manpage:`diff(1)`. +Also, please use the ``-p`` argument which shows which C function each +change is in - that makes the resultant ``diff`` a lot easier to read. +Patches should be based in the root kernel source directory, +not in any lower subdirectory. + +To create a patch for a single file, it is often sufficient to do:: + + SRCTREE= linux + MYFILE= drivers/net/mydriver.c + + cd $SRCTREE + cp $MYFILE $MYFILE.orig + vi $MYFILE # make your change + cd .. + diff -up $SRCTREE/$MYFILE{.orig,} > /tmp/patch + +To create a patch for multiple files, you should unpack a "vanilla", +or unmodified kernel source tree, and generate a ``diff`` against your +own source tree. For example:: + + MYSRC= /devel/linux + + tar xvfz linux-3.19.tar.gz + mv linux-3.19 linux-3.19-vanilla + diff -uprN -X linux-3.19-vanilla/Documentation/dontdiff \ + linux-3.19-vanilla $MYSRC > /tmp/patch + +``dontdiff`` is a list of files which are generated by the kernel during +the build process, and should be ignored in any :manpage:`diff(1)`-generated +patch. + +Make sure your patch does not include any extra files which do not +belong in a patch submission. Make sure to review your patch -after- +generating it with :manpage:`diff(1)`, to ensure accuracy. + +If your changes produce a lot of deltas, you need to split them into +individual patches which modify things in logical stages; see +:ref:`split_changes`. This will facilitate review by other kernel developers, +very important if you want your patch accepted. + +If you're using ``git``, ``git rebase -i`` can help you with this process. If +you're not using ``git``, ``quilt`` <http://savannah.nongnu.org/projects/quilt> +is another popular alternative. + +.. _describe_changes: + +2) Describe your changes +------------------------ + +Describe your problem. Whether your patch is a one-line bug fix or +5000 lines of a new feature, there must be an underlying problem that +motivated you to do this work. Convince the reviewer that there is a +problem worth fixing and that it makes sense for them to read past the +first paragraph. + +Describe user-visible impact. Straight up crashes and lockups are +pretty convincing, but not all bugs are that blatant. Even if the +problem was spotted during code review, describe the impact you think +it can have on users. Keep in mind that the majority of Linux +installations run kernels from secondary stable trees or +vendor/product-specific trees that cherry-pick only specific patches +from upstream, so include anything that could help route your change +downstream: provoking circumstances, excerpts from dmesg, crash +descriptions, performance regressions, latency spikes, lockups, etc. + +Quantify optimizations and trade-offs. If you claim improvements in +performance, memory consumption, stack footprint, or binary size, +include numbers that back them up. But also describe non-obvious +costs. Optimizations usually aren't free but trade-offs between CPU, +memory, and readability; or, when it comes to heuristics, between +different workloads. Describe the expected downsides of your +optimization so that the reviewer can weigh costs against benefits. + +Once the problem is established, describe what you are actually doing +about it in technical detail. It's important to describe the change +in plain English for the reviewer to verify that the code is behaving +as you intend it to. + +The maintainer will thank you if you write your patch description in a +form which can be easily pulled into Linux's source code management +system, ``git``, as a "commit log". See :ref:`explicit_in_reply_to`. + +Solve only one problem per patch. If your description starts to get +long, that's a sign that you probably need to split up your patch. +See :ref:`split_changes`. + +When you submit or resubmit a patch or patch series, include the +complete patch description and justification for it. Don't just +say that this is version N of the patch (series). Don't expect the +subsystem maintainer to refer back to earlier patch versions or referenced +URLs to find the patch description and put that into the patch. +I.e., the patch (series) and its description should be self-contained. +This benefits both the maintainers and reviewers. Some reviewers +probably didn't even receive earlier versions of the patch. + +Describe your changes in imperative mood, e.g. "make xyzzy do frotz" +instead of "[This patch] makes xyzzy do frotz" or "[I] changed xyzzy +to do frotz", as if you are giving orders to the codebase to change +its behaviour. + +If the patch fixes a logged bug entry, refer to that bug entry by +number and URL. If the patch follows from a mailing list discussion, +give a URL to the mailing list archive; use the https://lkml.kernel.org/ +redirector with a ``Message-Id``, to ensure that the links cannot become +stale. + +However, try to make your explanation understandable without external +resources. In addition to giving a URL to a mailing list archive or +bug, summarize the relevant points of the discussion that led to the +patch as submitted. + +If you want to refer to a specific commit, don't just refer to the +SHA-1 ID of the commit. Please also include the oneline summary of +the commit, to make it easier for reviewers to know what it is about. +Example:: + + Commit e21d2170f36602ae2708 ("video: remove unnecessary + platform_set_drvdata()") removed the unnecessary + platform_set_drvdata(), but left the variable "dev" unused, + delete it. + +You should also be sure to use at least the first twelve characters of the +SHA-1 ID. The kernel repository holds a *lot* of objects, making +collisions with shorter IDs a real possibility. Bear in mind that, even if +there is no collision with your six-character ID now, that condition may +change five years from now. + +If your patch fixes a bug in a specific commit, e.g. you found an issue using +``git bisect``, please use the 'Fixes:' tag with the first 12 characters of +the SHA-1 ID, and the one line summary. For example:: + + Fixes: e21d2170f366 ("video: remove unnecessary platform_set_drvdata()") + +The following ``git config`` settings can be used to add a pretty format for +outputting the above style in the ``git log`` or ``git show`` commands:: + + [core] + abbrev = 12 + [pretty] + fixes = Fixes: %h (\"%s\") + +.. _split_changes: + +3) Separate your changes +------------------------ + +Separate each **logical change** into a separate patch. + +For example, if your changes include both bug fixes and performance +enhancements for a single driver, separate those changes into two +or more patches. If your changes include an API update, and a new +driver which uses that new API, separate those into two patches. + +On the other hand, if you make a single change to numerous files, +group those changes into a single patch. Thus a single logical change +is contained within a single patch. + +The point to remember is that each patch should make an easily understood +change that can be verified by reviewers. Each patch should be justifiable +on its own merits. + +If one patch depends on another patch in order for a change to be +complete, that is OK. Simply note **"this patch depends on patch X"** +in your patch description. + +When dividing your change into a series of patches, take special care to +ensure that the kernel builds and runs properly after each patch in the +series. Developers using ``git bisect`` to track down a problem can end up +splitting your patch series at any point; they will not thank you if you +introduce bugs in the middle. + +If you cannot condense your patch set into a smaller set of patches, +then only post say 15 or so at a time and wait for review and integration. + + + +4) Style-check your changes +--------------------------- + +Check your patch for basic style violations, details of which can be +found in +:ref:`Documentation/process/coding-style.rst <codingstyle>`. +Failure to do so simply wastes +the reviewers time and will get your patch rejected, probably +without even being read. + +One significant exception is when moving code from one file to +another -- in this case you should not modify the moved code at all in +the same patch which moves it. This clearly delineates the act of +moving the code and your changes. This greatly aids review of the +actual differences and allows tools to better track the history of +the code itself. + +Check your patches with the patch style checker prior to submission +(scripts/checkpatch.pl). Note, though, that the style checker should be +viewed as a guide, not as a replacement for human judgment. If your code +looks better with a violation then its probably best left alone. + +The checker reports at three levels: + - ERROR: things that are very likely to be wrong + - WARNING: things requiring careful review + - CHECK: things requiring thought + +You should be able to justify all violations that remain in your +patch. + + +5) Select the recipients for your patch +--------------------------------------- + +You should always copy the appropriate subsystem maintainer(s) on any patch +to code that they maintain; look through the MAINTAINERS file and the +source code revision history to see who those maintainers are. The +script scripts/get_maintainer.pl can be very useful at this step. If you +cannot find a maintainer for the subsystem you are working on, Andrew +Morton (akpm@linux-foundation.org) serves as a maintainer of last resort. + +You should also normally choose at least one mailing list to receive a copy +of your patch set. linux-kernel@vger.kernel.org functions as a list of +last resort, but the volume on that list has caused a number of developers +to tune it out. Look in the MAINTAINERS file for a subsystem-specific +list; your patch will probably get more attention there. Please do not +spam unrelated lists, though. + +Many kernel-related lists are hosted on vger.kernel.org; you can find a +list of them at http://vger.kernel.org/vger-lists.html. There are +kernel-related lists hosted elsewhere as well, though. + +Do not send more than 15 patches at once to the vger mailing lists!!! + +Linus Torvalds is the final arbiter of all changes accepted into the +Linux kernel. His e-mail address is <torvalds@linux-foundation.org>. +He gets a lot of e-mail, and, at this point, very few patches go through +Linus directly, so typically you should do your best to -avoid- +sending him e-mail. + +If you have a patch that fixes an exploitable security bug, send that patch +to security@kernel.org. For severe bugs, a short embargo may be considered +to allow distributors to get the patch out to users; in such cases, +obviously, the patch should not be sent to any public lists. + +Patches that fix a severe bug in a released kernel should be directed +toward the stable maintainers by putting a line like this:: + + Cc: stable@vger.kernel.org + +into the sign-off area of your patch (note, NOT an email recipient). You +should also read +:ref:`Documentation/process/stable-kernel-rules.rst <stable_kernel_rules>` +in addition to this file. + +Note, however, that some subsystem maintainers want to come to their own +conclusions on which patches should go to the stable trees. The networking +maintainer, in particular, would rather not see individual developers +adding lines like the above to their patches. + +If changes affect userland-kernel interfaces, please send the MAN-PAGES +maintainer (as listed in the MAINTAINERS file) a man-pages patch, or at +least a notification of the change, so that some information makes its way +into the manual pages. User-space API changes should also be copied to +linux-api@vger.kernel.org. + +For small patches you may want to CC the Trivial Patch Monkey +trivial@kernel.org which collects "trivial" patches. Have a look +into the MAINTAINERS file for its current manager. + +Trivial patches must qualify for one of the following rules: + +- Spelling fixes in documentation +- Spelling fixes for errors which could break :manpage:`grep(1)` +- Warning fixes (cluttering with useless warnings is bad) +- Compilation fixes (only if they are actually correct) +- Runtime fixes (only if they actually fix things) +- Removing use of deprecated functions/macros +- Contact detail and documentation fixes +- Non-portable code replaced by portable code (even in arch-specific, + since people copy, as long as it's trivial) +- Any fix by the author/maintainer of the file (ie. patch monkey + in re-transmission mode) + + + +6) No MIME, no links, no compression, no attachments. Just plain text +---------------------------------------------------------------------- + +Linus and other kernel developers need to be able to read and comment +on the changes you are submitting. It is important for a kernel +developer to be able to "quote" your changes, using standard e-mail +tools, so that they may comment on specific portions of your code. + +For this reason, all patches should be submitted by e-mail "inline". + +.. warning:: + + Be wary of your editor's word-wrap corrupting your patch, + if you choose to cut-n-paste your patch. + +Do not attach the patch as a MIME attachment, compressed or not. +Many popular e-mail applications will not always transmit a MIME +attachment as plain text, making it impossible to comment on your +code. A MIME attachment also takes Linus a bit more time to process, +decreasing the likelihood of your MIME-attached change being accepted. + +Exception: If your mailer is mangling patches then someone may ask +you to re-send them using MIME. + +See :ref:`Documentation/process/email-clients.rst <email_clients>` +for hints about configuring your e-mail client so that it sends your patches +untouched. + +7) E-mail size +-------------- + +Large changes are not appropriate for mailing lists, and some +maintainers. If your patch, uncompressed, exceeds 300 kB in size, +it is preferred that you store your patch on an Internet-accessible +server, and provide instead a URL (link) pointing to your patch. But note +that if your patch exceeds 300 kB, it almost certainly needs to be broken up +anyway. + +8) Respond to review comments +----------------------------- + +Your patch will almost certainly get comments from reviewers on ways in +which the patch can be improved. You must respond to those comments; +ignoring reviewers is a good way to get ignored in return. Review comments +or questions that do not lead to a code change should almost certainly +bring about a comment or changelog entry so that the next reviewer better +understands what is going on. + +Be sure to tell the reviewers what changes you are making and to thank them +for their time. Code review is a tiring and time-consuming process, and +reviewers sometimes get grumpy. Even in that case, though, respond +politely and address the problems they have pointed out. + + +9) Don't get discouraged - or impatient +--------------------------------------- + +After you have submitted your change, be patient and wait. Reviewers are +busy people and may not get to your patch right away. + +Once upon a time, patches used to disappear into the void without comment, +but the development process works more smoothly than that now. You should +receive comments within a week or so; if that does not happen, make sure +that you have sent your patches to the right place. Wait for a minimum of +one week before resubmitting or pinging reviewers - possibly longer during +busy times like merge windows. + + +10) Include PATCH in the subject +-------------------------------- + +Due to high e-mail traffic to Linus, and to linux-kernel, it is common +convention to prefix your subject line with [PATCH]. This lets Linus +and other kernel developers more easily distinguish patches from other +e-mail discussions. + + + +11) Sign your work +------------------ + +To improve tracking of who did what, especially with patches that can +percolate to their final resting place in the kernel through several +layers of maintainers, we've introduced a "sign-off" procedure on +patches that are being emailed around. + +The sign-off is a simple line at the end of the explanation for the +patch, which certifies that you wrote it or otherwise have the right to +pass it on as an open-source patch. The rules are pretty simple: if you +can certify the below: + +Developer's Certificate of Origin 1.1 +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +By making a contribution to this project, I certify that: + + (a) The contribution was created in whole or in part by me and I + have the right to submit it under the open source license + indicated in the file; or + + (b) The contribution is based upon previous work that, to the best + of my knowledge, is covered under an appropriate open source + license and I have the right under that license to submit that + work with modifications, whether created in whole or in part + by me, under the same open source license (unless I am + permitted to submit under a different license), as indicated + in the file; or + + (c) The contribution was provided directly to me by some other + person who certified (a), (b) or (c) and I have not modified + it. + + (d) I understand and agree that this project and the contribution + are public and that a record of the contribution (including all + personal information I submit with it, including my sign-off) is + maintained indefinitely and may be redistributed consistent with + this project or the open source license(s) involved. + +then you just add a line saying:: + + Signed-off-by: Random J Developer <random@developer.example.org> + +using your real name (sorry, no pseudonyms or anonymous contributions.) + +Some people also put extra tags at the end. They'll just be ignored for +now, but you can do this to mark internal company procedures or just +point out some special detail about the sign-off. + +If you are a subsystem or branch maintainer, sometimes you need to slightly +modify patches you receive in order to merge them, because the code is not +exactly the same in your tree and the submitters'. If you stick strictly to +rule (c), you should ask the submitter to rediff, but this is a totally +counter-productive waste of time and energy. Rule (b) allows you to adjust +the code, but then it is very impolite to change one submitter's code and +make him endorse your bugs. To solve this problem, it is recommended that +you add a line between the last Signed-off-by header and yours, indicating +the nature of your changes. While there is nothing mandatory about this, it +seems like prepending the description with your mail and/or name, all +enclosed in square brackets, is noticeable enough to make it obvious that +you are responsible for last-minute changes. Example:: + + Signed-off-by: Random J Developer <random@developer.example.org> + [lucky@maintainer.example.org: struct foo moved from foo.c to foo.h] + Signed-off-by: Lucky K Maintainer <lucky@maintainer.example.org> + +This practice is particularly helpful if you maintain a stable branch and +want at the same time to credit the author, track changes, merge the fix, +and protect the submitter from complaints. Note that under no circumstances +can you change the author's identity (the From header), as it is the one +which appears in the changelog. + +Special note to back-porters: It seems to be a common and useful practice +to insert an indication of the origin of a patch at the top of the commit +message (just after the subject line) to facilitate tracking. For instance, +here's what we see in a 3.x-stable release:: + + Date: Tue Oct 7 07:26:38 2014 -0400 + + libata: Un-break ATA blacklist + + commit 1c40279960bcd7d52dbdf1d466b20d24b99176c8 upstream. + +And here's what might appear in an older kernel once a patch is backported:: + + Date: Tue May 13 22:12:27 2008 +0200 + + wireless, airo: waitbusy() won't delay + + [backport of 2.6 commit b7acbdfbd1f277c1eb23f344f899cfa4cd0bf36a] + +Whatever the format, this information provides a valuable help to people +tracking your trees, and to people trying to troubleshoot bugs in your +tree. + + +12) When to use Acked-by: and Cc: +--------------------------------- + +The Signed-off-by: tag indicates that the signer was involved in the +development of the patch, or that he/she was in the patch's delivery path. + +If a person was not directly involved in the preparation or handling of a +patch but wishes to signify and record their approval of it then they can +ask to have an Acked-by: line added to the patch's changelog. + +Acked-by: is often used by the maintainer of the affected code when that +maintainer neither contributed to nor forwarded the patch. + +Acked-by: is not as formal as Signed-off-by:. It is a record that the acker +has at least reviewed the patch and has indicated acceptance. Hence patch +mergers will sometimes manually convert an acker's "yep, looks good to me" +into an Acked-by: (but note that it is usually better to ask for an +explicit ack). + +Acked-by: does not necessarily indicate acknowledgement of the entire patch. +For example, if a patch affects multiple subsystems and has an Acked-by: from +one subsystem maintainer then this usually indicates acknowledgement of just +the part which affects that maintainer's code. Judgement should be used here. +When in doubt people should refer to the original discussion in the mailing +list archives. + +If a person has had the opportunity to comment on a patch, but has not +provided such comments, you may optionally add a ``Cc:`` tag to the patch. +This is the only tag which might be added without an explicit action by the +person it names - but it should indicate that this person was copied on the +patch. This tag documents that potentially interested parties +have been included in the discussion. + + +13) Using Reported-by:, Tested-by:, Reviewed-by:, Suggested-by: and Fixes: +-------------------------------------------------------------------------- + +The Reported-by tag gives credit to people who find bugs and report them and it +hopefully inspires them to help us again in the future. Please note that if +the bug was reported in private, then ask for permission first before using the +Reported-by tag. + +A Tested-by: tag indicates that the patch has been successfully tested (in +some environment) by the person named. This tag informs maintainers that +some testing has been performed, provides a means to locate testers for +future patches, and ensures credit for the testers. + +Reviewed-by:, instead, indicates that the patch has been reviewed and found +acceptable according to the Reviewer's Statement: + +Reviewer's statement of oversight +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +By offering my Reviewed-by: tag, I state that: + + (a) I have carried out a technical review of this patch to + evaluate its appropriateness and readiness for inclusion into + the mainline kernel. + + (b) Any problems, concerns, or questions relating to the patch + have been communicated back to the submitter. I am satisfied + with the submitter's response to my comments. + + (c) While there may be things that could be improved with this + submission, I believe that it is, at this time, (1) a + worthwhile modification to the kernel, and (2) free of known + issues which would argue against its inclusion. + + (d) While I have reviewed the patch and believe it to be sound, I + do not (unless explicitly stated elsewhere) make any + warranties or guarantees that it will achieve its stated + purpose or function properly in any given situation. + +A Reviewed-by tag is a statement of opinion that the patch is an +appropriate modification of the kernel without any remaining serious +technical issues. Any interested reviewer (who has done the work) can +offer a Reviewed-by tag for a patch. This tag serves to give credit to +reviewers and to inform maintainers of the degree of review which has been +done on the patch. Reviewed-by: tags, when supplied by reviewers known to +understand the subject area and to perform thorough reviews, will normally +increase the likelihood of your patch getting into the kernel. + +A Suggested-by: tag indicates that the patch idea is suggested by the person +named and ensures credit to the person for the idea. Please note that this +tag should not be added without the reporter's permission, especially if the +idea was not posted in a public forum. That said, if we diligently credit our +idea reporters, they will, hopefully, be inspired to help us again in the +future. + +A Fixes: tag indicates that the patch fixes an issue in a previous commit. It +is used to make it easy to determine where a bug originated, which can help +review a bug fix. This tag also assists the stable kernel team in determining +which stable kernel versions should receive your fix. This is the preferred +method for indicating a bug fixed by the patch. See :ref:`describe_changes` +for more details. + + +14) The canonical patch format +------------------------------ + +This section describes how the patch itself should be formatted. Note +that, if you have your patches stored in a ``git`` repository, proper patch +formatting can be had with ``git format-patch``. The tools cannot create +the necessary text, though, so read the instructions below anyway. + +The canonical patch subject line is:: + + Subject: [PATCH 001/123] subsystem: summary phrase + +The canonical patch message body contains the following: + + - A ``from`` line specifying the patch author (only needed if the person + sending the patch is not the author). + + - An empty line. + + - The body of the explanation, line wrapped at 75 columns, which will + be copied to the permanent changelog to describe this patch. + + - The ``Signed-off-by:`` lines, described above, which will + also go in the changelog. + + - A marker line containing simply ``---``. + + - Any additional comments not suitable for the changelog. + + - The actual patch (``diff`` output). + +The Subject line format makes it very easy to sort the emails +alphabetically by subject line - pretty much any email reader will +support that - since because the sequence number is zero-padded, +the numerical and alphabetic sort is the same. + +The ``subsystem`` in the email's Subject should identify which +area or subsystem of the kernel is being patched. + +The ``summary phrase`` in the email's Subject should concisely +describe the patch which that email contains. The ``summary +phrase`` should not be a filename. Do not use the same ``summary +phrase`` for every patch in a whole patch series (where a ``patch +series`` is an ordered sequence of multiple, related patches). + +Bear in mind that the ``summary phrase`` of your email becomes a +globally-unique identifier for that patch. It propagates all the way +into the ``git`` changelog. The ``summary phrase`` may later be used in +developer discussions which refer to the patch. People will want to +google for the ``summary phrase`` to read discussion regarding that +patch. It will also be the only thing that people may quickly see +when, two or three months later, they are going through perhaps +thousands of patches using tools such as ``gitk`` or ``git log +--oneline``. + +For these reasons, the ``summary`` must be no more than 70-75 +characters, and it must describe both what the patch changes, as well +as why the patch might be necessary. It is challenging to be both +succinct and descriptive, but that is what a well-written summary +should do. + +The ``summary phrase`` may be prefixed by tags enclosed in square +brackets: "Subject: [PATCH <tag>...] <summary phrase>". The tags are +not considered part of the summary phrase, but describe how the patch +should be treated. Common tags might include a version descriptor if +the multiple versions of the patch have been sent out in response to +comments (i.e., "v1, v2, v3"), or "RFC" to indicate a request for +comments. If there are four patches in a patch series the individual +patches may be numbered like this: 1/4, 2/4, 3/4, 4/4. This assures +that developers understand the order in which the patches should be +applied and that they have reviewed or applied all of the patches in +the patch series. + +A couple of example Subjects:: + + Subject: [PATCH 2/5] ext2: improve scalability of bitmap searching + Subject: [PATCH v2 01/27] x86: fix eflags tracking + +The ``from`` line must be the very first line in the message body, +and has the form: + + From: Original Author <author@example.com> + +The ``from`` line specifies who will be credited as the author of the +patch in the permanent changelog. If the ``from`` line is missing, +then the ``From:`` line from the email header will be used to determine +the patch author in the changelog. + +The explanation body will be committed to the permanent source +changelog, so should make sense to a competent reader who has long +since forgotten the immediate details of the discussion that might +have led to this patch. Including symptoms of the failure which the +patch addresses (kernel log messages, oops messages, etc.) is +especially useful for people who might be searching the commit logs +looking for the applicable patch. If a patch fixes a compile failure, +it may not be necessary to include _all_ of the compile failures; just +enough that it is likely that someone searching for the patch can find +it. As in the ``summary phrase``, it is important to be both succinct as +well as descriptive. + +The ``---`` marker line serves the essential purpose of marking for patch +handling tools where the changelog message ends. + +One good use for the additional comments after the ``---`` marker is for +a ``diffstat``, to show what files have changed, and the number of +inserted and deleted lines per file. A ``diffstat`` is especially useful +on bigger patches. Other comments relevant only to the moment or the +maintainer, not suitable for the permanent changelog, should also go +here. A good example of such comments might be ``patch changelogs`` +which describe what has changed between the v1 and v2 version of the +patch. + +If you are going to include a ``diffstat`` after the ``---`` marker, please +use ``diffstat`` options ``-p 1 -w 70`` so that filenames are listed from +the top of the kernel source tree and don't use too much horizontal +space (easily fit in 80 columns, maybe with some indentation). (``git`` +generates appropriate diffstats by default.) + +See more details on the proper patch format in the following +references. + +.. _explicit_in_reply_to: + +15) Explicit In-Reply-To headers +-------------------------------- + +It can be helpful to manually add In-Reply-To: headers to a patch +(e.g., when using ``git send-email``) to associate the patch with +previous relevant discussion, e.g. to link a bug fix to the email with +the bug report. However, for a multi-patch series, it is generally +best to avoid using In-Reply-To: to link to older versions of the +series. This way multiple versions of the patch don't become an +unmanageable forest of references in email clients. If a link is +helpful, you can use the https://lkml.kernel.org/ redirector (e.g., in +the cover email text) to link to an earlier version of the patch series. + + +16) Sending ``git pull`` requests +--------------------------------- + +If you have a series of patches, it may be most convenient to have the +maintainer pull them directly into the subsystem repository with a +``git pull`` operation. Note, however, that pulling patches from a developer +requires a higher degree of trust than taking patches from a mailing list. +As a result, many subsystem maintainers are reluctant to take pull +requests, especially from new, unknown developers. If in doubt you can use +the pull request as the cover letter for a normal posting of the patch +series, giving the maintainer the option of using either. + +A pull request should have [GIT] or [PULL] in the subject line. The +request itself should include the repository name and the branch of +interest on a single line; it should look something like:: + + Please pull from + + git://jdelvare.pck.nerim.net/jdelvare-2.6 i2c-for-linus + + to get these changes: + +A pull request should also include an overall message saying what will be +included in the request, a ``git shortlog`` listing of the patches +themselves, and a ``diffstat`` showing the overall effect of the patch series. +The easiest way to get all this information together is, of course, to let +``git`` do it for you with the ``git request-pull`` command. + +Some maintainers (including Linus) want to see pull requests from signed +commits; that increases their confidence that the request actually came +from you. Linus, in particular, will not pull from public hosting sites +like GitHub in the absence of a signed tag. + +The first step toward creating such tags is to make a GNUPG key and get it +signed by one or more core kernel developers. This step can be hard for +new developers, but there is no way around it. Attending conferences can +be a good way to find developers who can sign your key. + +Once you have prepared a patch series in ``git`` that you wish to have somebody +pull, create a signed tag with ``git tag -s``. This will create a new tag +identifying the last commit in the series and containing a signature +created with your private key. You will also have the opportunity to add a +changelog-style message to the tag; this is an ideal place to describe the +effects of the pull request as a whole. + +If the tree the maintainer will be pulling from is not the repository you +are working from, don't forget to push the signed tag explicitly to the +public tree. + +When generating your pull request, use the signed tag as the target. A +command like this will do the trick:: + + git request-pull master git://my.public.tree/linux.git my-signed-tag + + +REFERENCES +********** + +Andrew Morton, "The perfect patch" (tpp). + <http://www.ozlabs.org/~akpm/stuff/tpp.txt> + +Jeff Garzik, "Linux kernel patch submission format". + <http://linux.yyz.us/patch-format.html> + +Greg Kroah-Hartman, "How to piss off a kernel subsystem maintainer". + <http://www.kroah.com/log/linux/maintainer.html> + + <http://www.kroah.com/log/linux/maintainer-02.html> + + <http://www.kroah.com/log/linux/maintainer-03.html> + + <http://www.kroah.com/log/linux/maintainer-04.html> + + <http://www.kroah.com/log/linux/maintainer-05.html> + + <http://www.kroah.com/log/linux/maintainer-06.html> + +NO!!!! No more huge patch bombs to linux-kernel@vger.kernel.org people! + <https://lkml.org/lkml/2005/7/11/336> + +Kernel Documentation/process/coding-style.rst: + :ref:`Documentation/process/coding-style.rst <codingstyle>` + +Linus Torvalds's mail on the canonical patch format: + <http://lkml.org/lkml/2005/4/7/183> + +Andi Kleen, "On submitting kernel patches" + Some strategies to get difficult or controversial changes in. + + http://halobates.de/on-submitting-patches.pdf diff --git a/Documentation/volatile-considered-harmful.txt b/Documentation/process/volatile-considered-harmful.rst index db0cb22..e0d042a 100644 --- a/Documentation/volatile-considered-harmful.txt +++ b/Documentation/process/volatile-considered-harmful.rst @@ -22,7 +22,7 @@ need to use volatile as well. If volatile is still necessary, there is almost certainly a bug in the code somewhere. In properly-written kernel code, volatile can only serve to slow things down. -Consider a typical block of kernel code: +Consider a typical block of kernel code:: spin_lock(&the_lock); do_something_on(&shared_data); @@ -57,7 +57,7 @@ optimization, so, once again, volatile is unnecessary. Another situation where one might be tempted to use volatile is when the processor is busy-waiting on the value of a variable. The right -way to perform a busy wait is: +way to perform a busy wait is:: while (my_variable != what_i_want) cpu_relax(); @@ -103,17 +103,20 @@ they come with a justification which shows that the concurrency issues have been properly thought through. -NOTES ------ +References +========== [1] http://lwn.net/Articles/233481/ + [2] http://lwn.net/Articles/233482/ -CREDITS -------- +Credits +======= Original impetus and research by Randy Dunlap + Written by Jonathan Corbet + Improvements via comments from Satyam Sharma, Johannes Stezenbach, Jesper - Juhl, Heikki Orsila, H. Peter Anvin, Philipp Hahn, and Stefan - Richter. +Juhl, Heikki Orsila, H. Peter Anvin, Philipp Hahn, and Stefan +Richter. diff --git a/Documentation/rfkill.txt b/Documentation/rfkill.txt index 1f0c270..8c17406 100644 --- a/Documentation/rfkill.txt +++ b/Documentation/rfkill.txt @@ -26,7 +26,7 @@ whether they can be changed or not: the system software. The rfkill subsystem has two parameters, rfkill.default_state and -rfkill.master_switch_mode, which are documented in kernel-parameters.txt. +rfkill.master_switch_mode, which are documented in admin-guide/kernel-parameters.rst. 2. Implementation details diff --git a/Documentation/scsi/scsi-parameters.txt b/Documentation/scsi/scsi-parameters.txt index 8e66daf..8477655 100644 --- a/Documentation/scsi/scsi-parameters.txt +++ b/Documentation/scsi/scsi-parameters.txt @@ -1,7 +1,7 @@ SCSI Kernel Parameters ~~~~~~~~~~~~~~~~~~~~~~ -See Documentation/kernel-parameters.txt for general information on +See Documentation/admin-guide/kernel-parameters.rst for general information on specifying module parameters. This document may not be entirely up to date and comprehensive. The command diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt index 2550751..6338400 100644 --- a/Documentation/scsi/scsi_mid_low_api.txt +++ b/Documentation/scsi/scsi_mid_low_api.txt @@ -336,7 +336,7 @@ in parallel by these functions. Conventions =========== First, Linus Torvalds's thoughts on C coding style can be found in the -Documentation/CodingStyle file. +Documentation/process/coding-style.rst file. Next, there is a movement to "outlaw" typedefs introducing synonyms for struct tags. Both can be still found in the SCSI subsystem, but diff --git a/Documentation/scsi/sym53c8xx_2.txt b/Documentation/scsi/sym53c8xx_2.txt index 6af8f7a..d281865 100644 --- a/Documentation/scsi/sym53c8xx_2.txt +++ b/Documentation/scsi/sym53c8xx_2.txt @@ -427,7 +427,7 @@ Synchronous transfers frequency (default answer: 80) 10.1 Syntax Setup commands can be passed to the driver either at boot time or as -parameters to modprobe, as described in Documentation/kernel-parameters.txt +parameters to modprobe, as described in Documentation/admin-guide/kernel-parameters.rst Example of boot setup command under lilo prompt: diff --git a/Documentation/sound/alsa/alsa-parameters.txt b/Documentation/sound/alsa/alsa-parameters.txt index 0fa4067..72eced8 100644 --- a/Documentation/sound/alsa/alsa-parameters.txt +++ b/Documentation/sound/alsa/alsa-parameters.txt @@ -1,7 +1,7 @@ ALSA Kernel Parameters ~~~~~~~~~~~~~~~~~~~~~~ -See Documentation/kernel-parameters.txt for general information on +See Documentation/admin-guide/kernel-parameters.rst for general information on specifying module parameters. This document may not be entirely up to date and comprehensive. The command diff --git a/Documentation/sound/oss/oss-parameters.txt b/Documentation/sound/oss/oss-parameters.txt index 3ab391e..cc675f2 100644 --- a/Documentation/sound/oss/oss-parameters.txt +++ b/Documentation/sound/oss/oss-parameters.txt @@ -1,7 +1,7 @@ OSS Kernel Parameters ~~~~~~~~~~~~~~~~~~~~~ -See Documentation/kernel-parameters.txt for general information on +See Documentation/admin-guide/kernel-parameters.rst for general information on specifying module parameters. This document may not be entirely up to date and comprehensive. The command diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index ffab8b5..6bb78f8 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -71,7 +71,7 @@ show up in /proc/sys/kernel: - printk_ratelimit_burst - pty ==> Documentation/filesystems/devpts.txt - randomize_va_space -- real-root-dev ==> Documentation/initrd.txt +- real-root-dev ==> Documentation/admin-guide/initrd.rst - reboot-cmd [ SPARC only ] - rtsig-max - rtsig-nr @@ -453,7 +453,7 @@ in a KVM virtual machine. This default can be overridden by adding nmi_watchdog=1 -to the guest kernel command line (see Documentation/kernel-parameters.txt). +to the guest kernel command line (see Documentation/admin-guide/kernel-parameters.rst). ============================================================== diff --git a/Documentation/sysfs-rules.txt b/Documentation/sysfs-rules.txt deleted file mode 100644 index ce60ffa..0000000 --- a/Documentation/sysfs-rules.txt +++ /dev/null @@ -1,184 +0,0 @@ -Rules on how to access information in the Linux kernel sysfs - -The kernel-exported sysfs exports internal kernel implementation details -and depends on internal kernel structures and layout. It is agreed upon -by the kernel developers that the Linux kernel does not provide a stable -internal API. Therefore, there are aspects of the sysfs interface that -may not be stable across kernel releases. - -To minimize the risk of breaking users of sysfs, which are in most cases -low-level userspace applications, with a new kernel release, the users -of sysfs must follow some rules to use an as-abstract-as-possible way to -access this filesystem. The current udev and HAL programs already -implement this and users are encouraged to plug, if possible, into the -abstractions these programs provide instead of accessing sysfs directly. - -But if you really do want or need to access sysfs directly, please follow -the following rules and then your programs should work with future -versions of the sysfs interface. - -- Do not use libsysfs - It makes assumptions about sysfs which are not true. Its API does not - offer any abstraction, it exposes all the kernel driver-core - implementation details in its own API. Therefore it is not better than - reading directories and opening the files yourself. - Also, it is not actively maintained, in the sense of reflecting the - current kernel development. The goal of providing a stable interface - to sysfs has failed; it causes more problems than it solves. It - violates many of the rules in this document. - -- sysfs is always at /sys - Parsing /proc/mounts is a waste of time. Other mount points are a - system configuration bug you should not try to solve. For test cases, - possibly support a SYSFS_PATH environment variable to overwrite the - application's behavior, but never try to search for sysfs. Never try - to mount it, if you are not an early boot script. - -- devices are only "devices" - There is no such thing like class-, bus-, physical devices, - interfaces, and such that you can rely on in userspace. Everything is - just simply a "device". Class-, bus-, physical, ... types are just - kernel implementation details which should not be expected by - applications that look for devices in sysfs. - - The properties of a device are: - o devpath (/devices/pci0000:00/0000:00:1d.1/usb2/2-2/2-2:1.0) - - identical to the DEVPATH value in the event sent from the kernel - at device creation and removal - - the unique key to the device at that point in time - - the kernel's path to the device directory without the leading - /sys, and always starting with a slash - - all elements of a devpath must be real directories. Symlinks - pointing to /sys/devices must always be resolved to their real - target and the target path must be used to access the device. - That way the devpath to the device matches the devpath of the - kernel used at event time. - - using or exposing symlink values as elements in a devpath string - is a bug in the application - - o kernel name (sda, tty, 0000:00:1f.2, ...) - - a directory name, identical to the last element of the devpath - - applications need to handle spaces and characters like '!' in - the name - - o subsystem (block, tty, pci, ...) - - simple string, never a path or a link - - retrieved by reading the "subsystem"-link and using only the - last element of the target path - - o driver (tg3, ata_piix, uhci_hcd) - - a simple string, which may contain spaces, never a path or a - link - - it is retrieved by reading the "driver"-link and using only the - last element of the target path - - devices which do not have "driver"-link just do not have a - driver; copying the driver value in a child device context is a - bug in the application - - o attributes - - the files in the device directory or files below subdirectories - of the same device directory - - accessing attributes reached by a symlink pointing to another device, - like the "device"-link, is a bug in the application - - Everything else is just a kernel driver-core implementation detail - that should not be assumed to be stable across kernel releases. - -- Properties of parent devices never belong into a child device. - Always look at the parent devices themselves for determining device - context properties. If the device 'eth0' or 'sda' does not have a - "driver"-link, then this device does not have a driver. Its value is empty. - Never copy any property of the parent-device into a child-device. Parent - device properties may change dynamically without any notice to the - child device. - -- Hierarchy in a single device tree - There is only one valid place in sysfs where hierarchy can be examined - and this is below: /sys/devices. - It is planned that all device directories will end up in the tree - below this directory. - -- Classification by subsystem - There are currently three places for classification of devices: - /sys/block, /sys/class and /sys/bus. It is planned that these will - not contain any device directories themselves, but only flat lists of - symlinks pointing to the unified /sys/devices tree. - All three places have completely different rules on how to access - device information. It is planned to merge all three - classification directories into one place at /sys/subsystem, - following the layout of the bus directories. All buses and - classes, including the converted block subsystem, will show up - there. - The devices belonging to a subsystem will create a symlink in the - "devices" directory at /sys/subsystem/<name>/devices. - - If /sys/subsystem exists, /sys/bus, /sys/class and /sys/block can be - ignored. If it does not exist, you always have to scan all three - places, as the kernel is free to move a subsystem from one place to - the other, as long as the devices are still reachable by the same - subsystem name. - - Assuming /sys/class/<subsystem> and /sys/bus/<subsystem>, or - /sys/block and /sys/class/block are not interchangeable is a bug in - the application. - -- Block - The converted block subsystem at /sys/class/block or - /sys/subsystem/block will contain the links for disks and partitions - at the same level, never in a hierarchy. Assuming the block subsystem to - contain only disks and not partition devices in the same flat list is - a bug in the application. - -- "device"-link and <subsystem>:<kernel name>-links - Never depend on the "device"-link. The "device"-link is a workaround - for the old layout, where class devices are not created in - /sys/devices/ like the bus devices. If the link-resolving of a - device directory does not end in /sys/devices/, you can use the - "device"-link to find the parent devices in /sys/devices/. That is the - single valid use of the "device"-link; it must never appear in any - path as an element. Assuming the existence of the "device"-link for - a device in /sys/devices/ is a bug in the application. - Accessing /sys/class/net/eth0/device is a bug in the application. - - Never depend on the class-specific links back to the /sys/class - directory. These links are also a workaround for the design mistake - that class devices are not created in /sys/devices. If a device - directory does not contain directories for child devices, these links - may be used to find the child devices in /sys/class. That is the single - valid use of these links; they must never appear in any path as an - element. Assuming the existence of these links for devices which are - real child device directories in the /sys/devices tree is a bug in - the application. - - It is planned to remove all these links when all class device - directories live in /sys/devices. - -- Position of devices along device chain can change. - Never depend on a specific parent device position in the devpath, - or the chain of parent devices. The kernel is free to insert devices into - the chain. You must always request the parent device you are looking for - by its subsystem value. You need to walk up the chain until you find - the device that matches the expected subsystem. Depending on a specific - position of a parent device or exposing relative paths using "../" to - access the chain of parents is a bug in the application. - -- When reading and writing sysfs device attribute files, avoid dependency - on specific error codes wherever possible. This minimizes coupling to - the error handling implementation within the kernel. - - In general, failures to read or write sysfs device attributes shall - propagate errors wherever possible. Common errors include, but are not - limited to: - - -EIO: The read or store operation is not supported, typically returned by - the sysfs system itself if the read or store pointer is NULL. - - -ENXIO: The read or store operation failed - - Error codes will not be changed without good reason, and should a change - to error codes result in user-space breakage, it will be fixed, or the - the offending change will be reverted. - - Userspace applications can, however, expect the format and contents of - the attribute files to remain consistent in the absence of a version - attribute change in the context of a given attribute. diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt deleted file mode 100644 index 3a3b30a..0000000 --- a/Documentation/sysrq.txt +++ /dev/null @@ -1,257 +0,0 @@ -Linux Magic System Request Key Hacks -Documentation for sysrq.c - -* What is the magic SysRq key? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -It is a 'magical' key combo you can hit which the kernel will respond to -regardless of whatever else it is doing, unless it is completely locked up. - -* How do I enable the magic SysRq key? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -You need to say "yes" to 'Magic SysRq key (CONFIG_MAGIC_SYSRQ)' when -configuring the kernel. When running a kernel with SysRq compiled in, -/proc/sys/kernel/sysrq controls the functions allowed to be invoked via -the SysRq key. The default value in this file is set by the -CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE config symbol, which itself defaults -to 1. Here is the list of possible values in /proc/sys/kernel/sysrq: - 0 - disable sysrq completely - 1 - enable all functions of sysrq - >1 - bitmask of allowed sysrq functions (see below for detailed function - description): - 2 = 0x2 - enable control of console logging level - 4 = 0x4 - enable control of keyboard (SAK, unraw) - 8 = 0x8 - enable debugging dumps of processes etc. - 16 = 0x10 - enable sync command - 32 = 0x20 - enable remount read-only - 64 = 0x40 - enable signalling of processes (term, kill, oom-kill) - 128 = 0x80 - allow reboot/poweroff - 256 = 0x100 - allow nicing of all RT tasks - -You can set the value in the file by the following command: - echo "number" >/proc/sys/kernel/sysrq - -The number may be written here either as decimal or as hexadecimal -with the 0x prefix. CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE must always be -written in hexadecimal. - -Note that the value of /proc/sys/kernel/sysrq influences only the invocation -via a keyboard. Invocation of any operation via /proc/sysrq-trigger is always -allowed (by a user with admin privileges). - -* How do I use the magic SysRq key? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -On x86 - You press the key combo 'ALT-SysRq-<command key>'. Note - Some - keyboards may not have a key labeled 'SysRq'. The 'SysRq' key is - also known as the 'Print Screen' key. Also some keyboards cannot - handle so many keys being pressed at the same time, so you might - have better luck with "press Alt", "press SysRq", "release SysRq", - "press <command key>", release everything. - -On SPARC - You press 'ALT-STOP-<command key>', I believe. - -On the serial console (PC style standard serial ports only) - - You send a BREAK, then within 5 seconds a command key. Sending - BREAK twice is interpreted as a normal BREAK. - -On PowerPC - Press 'ALT - Print Screen (or F13) - <command key>, - Print Screen (or F13) - <command key> may suffice. - -On other - If you know of the key combos for other architectures, please - let me know so I can add them to this section. - -On all - write a character to /proc/sysrq-trigger. e.g.: - - echo t > /proc/sysrq-trigger - -* What are the 'command' keys? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -'b' - Will immediately reboot the system without syncing or unmounting - your disks. - -'c' - Will perform a system crash by a NULL pointer dereference. - A crashdump will be taken if configured. - -'d' - Shows all locks that are held. - -'e' - Send a SIGTERM to all processes, except for init. - -'f' - Will call the oom killer to kill a memory hog process, but do not - panic if nothing can be killed. - -'g' - Used by kgdb (kernel debugger) - -'h' - Will display help (actually any other key than those listed - here will display help. but 'h' is easy to remember :-) - -'i' - Send a SIGKILL to all processes, except for init. - -'j' - Forcibly "Just thaw it" - filesystems frozen by the FIFREEZE ioctl. - -'k' - Secure Access Key (SAK) Kills all programs on the current virtual - console. NOTE: See important comments below in SAK section. - -'l' - Shows a stack backtrace for all active CPUs. - -'m' - Will dump current memory info to your console. - -'n' - Used to make RT tasks nice-able - -'o' - Will shut your system off (if configured and supported). - -'p' - Will dump the current registers and flags to your console. - -'q' - Will dump per CPU lists of all armed hrtimers (but NOT regular - timer_list timers) and detailed information about all - clockevent devices. - -'r' - Turns off keyboard raw mode and sets it to XLATE. - -'s' - Will attempt to sync all mounted filesystems. - -'t' - Will dump a list of current tasks and their information to your - console. - -'u' - Will attempt to remount all mounted filesystems read-only. - -'v' - Forcefully restores framebuffer console -'v' - Causes ETM buffer dump [ARM-specific] - -'w' - Dumps tasks that are in uninterruptable (blocked) state. - -'x' - Used by xmon interface on ppc/powerpc platforms. - Show global PMU Registers on sparc64. - Dump all TLB entries on MIPS. - -'y' - Show global CPU Registers [SPARC-64 specific] - -'z' - Dump the ftrace buffer - -'0'-'9' - Sets the console log level, controlling which kernel messages - will be printed to your console. ('0', for example would make - it so that only emergency messages like PANICs or OOPSes would - make it to your console.) - -* Okay, so what can I use them for? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -Well, unraw(r) is very handy when your X server or a svgalib program crashes. - -sak(k) (Secure Access Key) is useful when you want to be sure there is no -trojan program running at console which could grab your password -when you would try to login. It will kill all programs on given console, -thus letting you make sure that the login prompt you see is actually -the one from init, not some trojan program. -IMPORTANT: In its true form it is not a true SAK like the one in a :IMPORTANT -IMPORTANT: c2 compliant system, and it should not be mistaken as :IMPORTANT -IMPORTANT: such. :IMPORTANT - It seems others find it useful as (System Attention Key) which is -useful when you want to exit a program that will not let you switch consoles. -(For example, X or a svgalib program.) - -reboot(b) is good when you're unable to shut down. But you should also -sync(s) and umount(u) first. - -crash(c) can be used to manually trigger a crashdump when the system is hung. -Note that this just triggers a crash if there is no dump mechanism available. - -sync(s) is great when your system is locked up, it allows you to sync your -disks and will certainly lessen the chance of data loss and fscking. Note -that the sync hasn't taken place until you see the "OK" and "Done" appear -on the screen. (If the kernel is really in strife, you may not ever get the -OK or Done message...) - -umount(u) is basically useful in the same ways as sync(s). I generally sync(s), -umount(u), then reboot(b) when my system locks. It's saved me many a fsck. -Again, the unmount (remount read-only) hasn't taken place until you see the -"OK" and "Done" message appear on the screen. - -The loglevels '0'-'9' are useful when your console is being flooded with -kernel messages you do not want to see. Selecting '0' will prevent all but -the most urgent kernel messages from reaching your console. (They will -still be logged if syslogd/klogd are alive, though.) - -term(e) and kill(i) are useful if you have some sort of runaway process you -are unable to kill any other way, especially if it's spawning other -processes. - -"just thaw it(j)" is useful if your system becomes unresponsive due to a frozen -(probably root) filesystem via the FIFREEZE ioctl. - -* Sometimes SysRq seems to get 'stuck' after using it, what can I do? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -That happens to me, also. I've found that tapping shift, alt, and control -on both sides of the keyboard, and hitting an invalid sysrq sequence again -will fix the problem. (i.e., something like alt-sysrq-z). Switching to another -virtual console (ALT+Fn) and then back again should also help. - -* I hit SysRq, but nothing seems to happen, what's wrong? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -There are some keyboards that produce a different keycode for SysRq than the -pre-defined value of 99 (see KEY_SYSRQ in include/linux/input.h), or which -don't have a SysRq key at all. In these cases, run 'showkey -s' to find an -appropriate scancode sequence, and use 'setkeycodes <sequence> 99' to map -this sequence to the usual SysRq code (e.g., 'setkeycodes e05b 99'). It's -probably best to put this command in a boot script. Oh, and by the way, you -exit 'showkey' by not typing anything for ten seconds. - -* I want to add SysRQ key events to a module, how does it work? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -In order to register a basic function with the table, you must first include -the header 'include/linux/sysrq.h', this will define everything else you need. -Next, you must create a sysrq_key_op struct, and populate it with A) the key -handler function you will use, B) a help_msg string, that will print when SysRQ -prints help, and C) an action_msg string, that will print right before your -handler is called. Your handler must conform to the prototype in 'sysrq.h'. - -After the sysrq_key_op is created, you can call the kernel function -register_sysrq_key(int key, struct sysrq_key_op *op_p); this will -register the operation pointed to by 'op_p' at table key 'key', -if that slot in the table is blank. At module unload time, you must call -the function unregister_sysrq_key(int key, struct sysrq_key_op *op_p), which -will remove the key op pointed to by 'op_p' from the key 'key', if and only if -it is currently registered in that slot. This is in case the slot has been -overwritten since you registered it. - -The Magic SysRQ system works by registering key operations against a key op -lookup table, which is defined in 'drivers/tty/sysrq.c'. This key table has -a number of operations registered into it at compile time, but is mutable, -and 2 functions are exported for interface to it: - register_sysrq_key and unregister_sysrq_key. -Of course, never ever leave an invalid pointer in the table. I.e., when -your module that called register_sysrq_key() exits, it must call -unregister_sysrq_key() to clean up the sysrq key table entry that it used. -Null pointers in the table are always safe. :) - -If for some reason you feel the need to call the handle_sysrq function from -within a function called by handle_sysrq, you must be aware that you are in -a lock (you are also in an interrupt handler, which means don't sleep!), so -you must call __handle_sysrq_nolock instead. - -* When I hit a SysRq key combination only the header appears on the console? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -Sysrq output is subject to the same console loglevel control as all -other console output. This means that if the kernel was booted 'quiet' -as is common on distro kernels the output may not appear on the actual -console, even though it will appear in the dmesg buffer, and be accessible -via the dmesg command and to the consumers of /proc/kmsg. As a specific -exception the header line from the sysrq command is passed to all console -consumers as if the current loglevel was maximum. If only the header -is emitted it is almost certain that the kernel loglevel is too low. -Should you require the output on the console channel then you will need -to temporarily up the console loglevel using alt-sysrq-8 or: - - echo 8 > /proc/sysrq-trigger - -Remember to return the loglevel to normal after triggering the sysrq -command you are interested in. - -* I have more questions, who can I ask? -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -Just ask them on the linux-kernel mailing list: - linux-kernel@vger.kernel.org - -* Credits -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -Written by Mydraal <vulpyne@vulpyne.net> -Updated by Adam Sulmicki <adam@cfar.umd.edu> -Updated by Jeremy M. Dolan <jmd@turbogeek.org> 2001/01/28 10:15:59 -Added to by Crutcher Dunnavant <crutcher+kernel@datastacks.com> diff --git a/Documentation/virtual/kvm/review-checklist.txt b/Documentation/virtual/kvm/review-checklist.txt index a850986..a83b276 100644 --- a/Documentation/virtual/kvm/review-checklist.txt +++ b/Documentation/virtual/kvm/review-checklist.txt @@ -1,8 +1,8 @@ Review checklist for kvm patches ================================ -1. The patch must follow Documentation/CodingStyle and - Documentation/SubmittingPatches. +1. The patch must follow Documentation/process/coding-style.rst and + Documentation/process/submitting-patches.rst. 2. Patches should be against kvm.git master branch. diff --git a/Documentation/vm/numa b/Documentation/vm/numa index e0b58c0..a08f716 100644 --- a/Documentation/vm/numa +++ b/Documentation/vm/numa @@ -82,7 +82,7 @@ such as DMA or DMA32, represent relatively scarce resources. Linux chooses a default zonelist order based on the sizes of the various zone types relative to the total memory of the node and the total memory of the system. The default zonelist order may be overridden using the numa_zonelist_order kernel -boot parameter or sysctl. [see Documentation/kernel-parameters.txt and +boot parameter or sysctl. [see Documentation/admin-guide/kernel-parameters.rst and Documentation/sysctl/vm.txt] By default, Linux will attempt to satisfy memory allocation requests from the diff --git a/Documentation/watchdog/convert_drivers_to_kernel_api.txt b/Documentation/watchdog/convert_drivers_to_kernel_api.txt index 271b885..9fffb29 100644 --- a/Documentation/watchdog/convert_drivers_to_kernel_api.txt +++ b/Documentation/watchdog/convert_drivers_to_kernel_api.txt @@ -213,6 +213,6 @@ The entry for the driver now needs to select WATCHDOG_CORE: Create a patch and send it to upstream -------------------------------------- -Make sure you understood Documentation/SubmittingPatches and send your patch to +Make sure you understood Documentation/process/submitting-patches.rst and send your patch to linux-watchdog@vger.kernel.org. We are looking forward to it :) diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt index a8d3642..e21850e 100644 --- a/Documentation/watchdog/watchdog-parameters.txt +++ b/Documentation/watchdog/watchdog-parameters.txt @@ -4,7 +4,7 @@ be listed here unless the driver has its own driver-specific information file. -See Documentation/kernel-parameters.txt for information on +See Documentation/admin-guide/kernel-parameters.rst for information on providing kernel parameters for builtin drivers versus loadable modules. diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index 9da6f35..5e9b826 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -921,7 +921,7 @@ They should normally not be deleted from the kernel command line even though not all of them are actually meaningful to the kernel. Boot loader authors who need additional command line options for the boot loader itself should get them registered in -Documentation/kernel-parameters.txt to make sure they will not +Documentation/admin-guide/kernel-parameters.rst to make sure they will not conflict with actual kernel options now or in the future. vga=<mode> diff --git a/Documentation/zh_CN/CodingStyle b/Documentation/zh_CN/CodingStyle index 1271779..b027380 100644 --- a/Documentation/zh_CN/CodingStyle +++ b/Documentation/zh_CN/CodingStyle @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/CodingStyle +Chinese translated version of Documentation/process/coding-style.rst If you have any comment or update to the content, please post to LKML directly. However, if you have problem communicating in English you can also ask the @@ -7,7 +7,7 @@ translation is outdated or there is problem with translation. Chinese maintainer: Zhang Le <r0bertz@gentoo.org> --------------------------------------------------------------------- -Documentation/CodingStyle的中文翻译 +Documentation/process/coding-style.rst的中文翻译 如果想评论或更新本文的内容，请直接发信到LKML。如果你使用英文交流有困难的话，也可 以向中文版维护者求助。如果本翻译更新不及时或者翻译存在问题，请联系中文版维护者。 @@ -809,5 +809,5 @@ GNU 手册 - 遵循 K&R 标准和此文本 - cpp, gcc, gcc internals and indent, WG14是C语言的国际标准化工作组，URL: http://www.open-std.org/JTC1/SC22/WG14/ -Kernel CodingStyle，作者 greg@kroah.com 发表于OLS 2002： +Kernel process/coding-style.rst，作者 greg@kroah.com 发表于OLS 2002： http://www.kroah.com/linux/talks/ols_2002_kernel_codingstyle_talk/html/ diff --git a/Documentation/zh_CN/HOWTO b/Documentation/zh_CN/HOWTO index f0613b9..11be075 100644 --- a/Documentation/zh_CN/HOWTO +++ b/Documentation/zh_CN/HOWTO @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/HOWTO +Chinese translated version of Documentation/process/howto.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have a problem @@ -9,7 +9,7 @@ or if there is a problem with the translation. Maintainer: Greg Kroah-Hartman <greg@kroah.com> Chinese maintainer: Li Yang <leoli@freescale.com> --------------------------------------------------------------------- -Documentation/HOWTO 的中文翻译 +Documentation/process/howto.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 @@ -93,16 +93,16 @@ Linux内核代码中包含有大量的文档。这些文档对于学习如何与 文件简要介绍了Linux内核的背景，并且描述了如何配置和编译内核。内核的 新用户应该从这里开始。 - Documentation/Changes + Documentation/process/changes.rst 文件给出了用来编译和使用内核所需要的最小软件包列表。 - Documentation/CodingStyle + Documentation/process/coding-style.rst 描述Linux内核的代码风格和理由。所有新代码需要遵守这篇文档中定义的规 范。大多数维护者只会接收符合规定的补丁，很多人也只会帮忙检查符合风格 的代码。 - Documentation/SubmittingPatches - Documentation/SubmittingDrivers + Documentation/process/submitting-patches.rst + Documentation/process/submitting-drivers.rst 这两份文档明确描述如何创建和发送补丁，其中包括（但不仅限于)： - 邮件内容 - 邮件格式 @@ -116,7 +116,7 @@ Linux内核代码中包含有大量的文档。这些文档对于学习如何与 "Linux kernel patch submission format" http://linux.yyz.us/patch-format.html - Documentation/stable_api_nonsense.txt + Documentation/process/stable-api-nonsense.rst 论证内核为什么特意不包括稳定的内核内部API，也就是说不包括像这样的特 性： - 子系统中间层（为了兼容性？） @@ -125,23 +125,23 @@ Linux内核代码中包含有大量的文档。这些文档对于学习如何与 这篇文档对于理解Linux的开发哲学至关重要。对于将开发平台从其他操作系 统转移到Linux的人来说也很重要。 - Documentation/SecurityBugs + Documentation/admin-guide/security-bugs.rst 如果你认为自己发现了Linux内核的安全性问题，请根据这篇文档中的步骤来 提醒其他内核开发者并帮助解决这个问题。 - Documentation/ManagementStyle + Documentation/process/management-style.rst 描述内核维护者的工作方法及其共有特点。这对于刚刚接触内核开发（或者对 它感到好奇）的人来说很重要，因为它解释了很多对于内核维护者独特行为的 普遍误解与迷惑。 - Documentation/stable_kernel_rules.txt + Documentation/process/stable-kernel-rules.rst 解释了稳定版内核发布的规则，以及如何将改动放入这些版本的步骤。 - Documentation/kernel-docs.txt + Documentation/process/kernel-docs.rst 有助于内核开发的外部文档列表。如果你在内核自带的文档中没有找到你想找 的内容，可以查看这些文档。 - Documentation/applying-patches.txt + Documentation/process/applying-patches.rst 关于补丁是什么以及如何将它打在不同内核开发分支上的好介绍 内核还拥有大量从代码自动生成的文档。它包含内核内部API的全面介绍以及如何 @@ -238,7 +238,7 @@ kernel.org网站的pub/linux/kernel/v2.6/目录下找到它。它的开发遵循 2.6.x.y版本由“稳定版”小组（邮件地址<stable@vger.kernel.org>）维护，一般隔周发 布新版本。 -内核源码中的Documentation/stable_kernel_rules.txt文件具体描述了可被稳定 +内核源码中的Documentation/process/stable-kernel-rules.rst文件具体描述了可被稳定 版内核接受的修改类型以及发布的流程。 @@ -329,7 +329,7 @@ bugzilla.kernel.org是Linux内核开发者们用来跟踪内核Bug的网站。 户在这个工具中报告找到的所有bug。如何使用内核bugzilla的细节请访问： http://test.kernel.org/bugzilla/faq.html -内核源码主目录中的REPORTING-BUGS文件里有一个很好的模板。它指导用户如何报 +内核源码主目录中的admin-guide/reporting-bugs.rst文件里有一个很好的模板。它指导用户如何报 告可能的内核bug以及需要提供哪些信息来帮助内核开发者们找到问题的根源。 @@ -380,7 +380,7 @@ MAINTAINERS文件中可以找到不同话题对应的邮件列表。 这几行。将你的评论加在被引用的段落之间而不要放在邮件的顶部。 如果你在邮件中附带补丁，请确认它们是可以直接阅读的纯文本（如 -Documentation/SubmittingPatches文档中所述）。内核开发者们不希望遇到附件 +Documentation/process/submitting-patches.rst文档中所述）。内核开发者们不希望遇到附件 或者被压缩了的补丁。只有这样才能保证他们可以直接评论你的每行代码。请确保 你使用的邮件发送程序不会修改空格和制表符。一个防范性的测试方法是先将邮件 发送给自己，然后自己尝试是否可以顺利地打上收到的补丁。如果测试不成功，请 diff --git a/Documentation/zh_CN/SecurityBugs b/Documentation/zh_CN/SecurityBugs index d21eb07..2d0fffd 100644 --- a/Documentation/zh_CN/SecurityBugs +++ b/Documentation/zh_CN/SecurityBugs @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/SecurityBugs +Chinese translated version of Documentation/admin-guide/security-bugs.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have a problem @@ -8,7 +8,7 @@ or if there is a problem with the translation. Chinese maintainer: Harry Wei <harryxiyou@gmail.com> --------------------------------------------------------------------- -Documentation/SecurityBugs 的中文翻译 +Documentation/admin-guide/security-bugs.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 @@ -31,7 +31,7 @@ linux内核安全团队可以通过email<security@kernel.org>来联系。这是 一组独立的安全工作人员，可以帮助改善漏洞报告并且公布和取消一个修复。安 全团队有可能会从部分的维护者那里引进额外的帮助来了解并且修复安全漏洞。 当遇到任何漏洞，所能提供的信息越多就越能诊断和修复。如果你不清楚什么 -是有帮助的信息，那就请重温一下REPORTING-BUGS文件中的概述过程。任 +是有帮助的信息，那就请重温一下admin-guide/reporting-bugs.rst文件中的概述过程。任 何攻击性的代码都是非常有用的，未经报告者的同意不会被取消，除非它已经 被公布于众。 diff --git a/Documentation/zh_CN/SubmittingDrivers b/Documentation/zh_CN/SubmittingDrivers index d313f5d..929385e 100644 --- a/Documentation/zh_CN/SubmittingDrivers +++ b/Documentation/zh_CN/SubmittingDrivers @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/SubmittingDrivers +Chinese translated version of Documentation/process/submitting-drivers.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have a problem @@ -8,7 +8,7 @@ or if there is a problem with the translation. Chinese maintainer: Li Yang <leo@zh-kernel.org> --------------------------------------------------------------------- -Documentation/SubmittingDrivers 的中文翻译 +Documentation/process/submitting-drivers.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 @@ -30,7 +30,7 @@ Documentation/SubmittingDrivers 的中文翻译 兴趣的是显卡驱动程序，你也许应该访问 XFree86 项目(http://www.xfree86.org/) 和／或 X.org 项目 (http://x.org)。 -另请参阅 Documentation/SubmittingPatches 文档。 +另请参阅 Documentation/process/submitting-patches.rst 文档。 分配设备号 @@ -39,7 +39,7 @@ Documentation/SubmittingDrivers 的中文翻译 块设备和字符设备的主设备号与从设备号是由 Linux 命名编号分配权威 LANANA（ 现在是 Torben Mathiasen）负责分配。申请的网址是 http://www.lanana.org/。 即使不准备提交到主流内核的设备驱动也需要在这里分配设备号。有关详细信息， -请参阅 Documentation/devices.txt。 +请参阅 Documentation/admin-guide/devices.rst。 如果你使用的不是已经分配的设备号，那么当你提交设备驱动的时候，它将会被强 制分配一个新的设备号，即便这个设备号和你之前发给客户的截然不同。 @@ -81,7 +81,7 @@ Linux 2.6: 如果你需要一个 Linux 和 NT 的通用驱动接口，那么请在用 户空间实现它。 -代码： 请使用 Documentation/CodingStyle 中所描述的 Linux 代码风 +代码： 请使用 Documentation/process/coding-style.rst 中所描述的 Linux 代码风 格。如果你的某些代码段（例如那些与 Windows 驱动程序包共 享的代码段）需要使用其他格式，而你却只希望维护一份代码， 那么请将它们很好地区分出来，并且注明原因。 @@ -107,7 +107,7 @@ Linux 2.6: 程序测试的指导，请参阅 Documentation/power/drivers-testing.txt。有关驱动程序电 源管理问题相对全面的概述，请参阅 - Documentation/power/devices.txt。 + Documentation/power/admin-guide/devices.rst。 管理： 如果一个驱动程序的作者还在进行有效的维护，那么通常除了那 些明显正确且不需要任何检查的补丁以外，其他所有的补丁都会 diff --git a/Documentation/zh_CN/SubmittingPatches b/Documentation/zh_CN/SubmittingPatches index 1d3a10f..e9098da 100644 --- a/Documentation/zh_CN/SubmittingPatches +++ b/Documentation/zh_CN/SubmittingPatches @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/SubmittingPatches +Chinese translated version of Documentation/process/submitting-patches.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have a problem @@ -8,7 +8,7 @@ or if there is a problem with the translation. Chinese maintainer: TripleX Chung <triplex@zh-kernel.org> --------------------------------------------------------------------- -Documentation/SubmittingPatches 的中文翻译 +Documentation/process/submitting-patches.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 @@ -30,9 +30,9 @@ Documentation/SubmittingPatches 的中文翻译 对于想要将改动提交到 Linux 内核的个人或者公司来说，如果不熟悉“规矩”， 提交的流程会让人畏惧。本文档收集了一系列建议，这些建议可以大大的提高你 的改动被接受的机会。 -阅读 Documentation/SubmitChecklist 来获得在提交代码前需要检查的项目的列 +阅读 Documentation/process/submit-checklist.rst 来获得在提交代码前需要检查的项目的列 表。如果你在提交一个驱动程序，那么同时阅读一下 -Documentation/SubmittingDrivers 。 +Documentation/process/submitting-drivers.rst 。 -------------------------- @@ -338,7 +338,7 @@ e-mail 标题中的“一句话概述”扼要的描述 e-mail 中的补丁。 本节包含很多和提交到内核的代码有关的通常的"规则"。事情永远有例外...但是 你必须真的有好的理由这样做。你可以把本节叫做Linus的计算机科学入门课。 -1) 读 Document/CodingStyle +1) 读 Document/process/coding-style.rst Nuff 说过，如果你的代码和这个偏离太多，那么它有可能会被拒绝，没有更多的 审查，没有更多的评价。 @@ -404,8 +404,8 @@ Greg Kroah-Hartman, "How to piss off a kernel subsystem maintainer". NO!!!! No more huge patch bombs to linux-kernel@vger.kernel.org people! <https://lkml.org/lkml/2005/7/11/336> -Kernel Documentation/CodingStyle: - <http://sosdg.org/~coywolf/lxr/source/Documentation/CodingStyle> +Kernel Documentation/process/coding-style.rst: + <http://sosdg.org/~coywolf/lxr/source/Documentation/process/coding-style.rst> Linus Torvalds's mail on the canonical patch format: <http://lkml.org/lkml/2005/4/7/183> diff --git a/Documentation/zh_CN/arm/Booting b/Documentation/zh_CN/arm/Booting index 6158a64..1fe866f 100644 --- a/Documentation/zh_CN/arm/Booting +++ b/Documentation/zh_CN/arm/Booting @@ -68,7 +68,7 @@ RAM，或可能使用对这个设备已知的 RAM 信息，还可能使用任何 作为替代方案，引导加载程序也可以通过标签列表传递相关的'console=' 选项给内核以指定某个串口，而串口数据格式的选项在以下文档中描述： - Documentation/kernel-parameters.txt。 + Documentation/admin-guide/kernel-parameters.rst。 3、检测机器类型 diff --git a/Documentation/zh_CN/email-clients.txt b/Documentation/zh_CN/email-clients.txt index b9a1a3e..ec31d97 100644 --- a/Documentation/zh_CN/email-clients.txt +++ b/Documentation/zh_CN/email-clients.txt @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/email-clients.txt +Chinese translated version of Documentation/process/email-clients.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have a problem @@ -8,7 +8,7 @@ or if there is a problem with the translation. Chinese maintainer: Harry Wei <harryxiyou@gmail.com> --------------------------------------------------------------------- -Documentation/email-clients.txt 的中文翻译 +Documentation/process/email-clients.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 diff --git a/Documentation/zh_CN/oops-tracing.txt b/Documentation/zh_CN/oops-tracing.txt index 9312608..41ab53c 100644 --- a/Documentation/zh_CN/oops-tracing.txt +++ b/Documentation/zh_CN/oops-tracing.txt @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/oops-tracing.txt +Chinese translated version of Documentation/admin-guide/oops-tracing.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have a problem @@ -8,7 +8,7 @@ or if there is a problem with the translation. Chinese maintainer: Dave Young <hidave.darkstar@gmail.com> --------------------------------------------------------------------- -Documentation/oops-tracing.txt 的中文翻译 +Documentation/admin-guide/oops-tracing.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 @@ -50,7 +50,7 @@ cat /proc/kmsg > file， 然而你必须介入中止传输， kmsg是一个“ 息滚动到了终端的上面，你会发现以高分辩率启动（比如，vga=791）会让你读到更多的文 本。（注意：这需要vesafb，所以对‘早期’的oops没有帮助） -（2）用串口终端启动（请参看Documentation/serial-console.txt），运行一个null +（2）用串口终端启动（请参看Documentation/admin-guide/serial-console.rst），运行一个null modem到另一台机器并用你喜欢的通讯工具获取输出。Minicom工作地很好。 （3）使用Kdump（请参看Documentation/kdump/kdump.txt）， diff --git a/Documentation/zh_CN/stable_api_nonsense.txt b/Documentation/zh_CN/stable_api_nonsense.txt index c26a27d..a2b27fa 100644 --- a/Documentation/zh_CN/stable_api_nonsense.txt +++ b/Documentation/zh_CN/stable_api_nonsense.txt @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/stable_api_nonsense.txt +Chinese translated version of Documentation/process/stable-api-nonsense.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have problem @@ -9,7 +9,7 @@ is problem with translation. Maintainer: Greg Kroah-Hartman <greg@kroah.com> Chinese maintainer: TripleX Chung <zhongyu@18mail.cn> --------------------------------------------------------------------- -Documentation/stable_api_nonsense.txt 的中文翻译 +Documentation/process/stable-api-nonsense.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 diff --git a/Documentation/zh_CN/stable_kernel_rules.txt b/Documentation/zh_CN/stable_kernel_rules.txt index 26ea5ed..db4ba5a 100644 --- a/Documentation/zh_CN/stable_kernel_rules.txt +++ b/Documentation/zh_CN/stable_kernel_rules.txt @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/stable_kernel_rules.txt +Chinese translated version of Documentation/process/stable-kernel-rules.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have a problem @@ -8,7 +8,7 @@ or if there is a problem with the translation. Chinese maintainer: TripleX Chung <triplex@zh-kernel.org> --------------------------------------------------------------------- -Documentation/stable_kernel_rules.txt 的中文翻译 +Documentation/process/stable-kernel-rules.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 @@ -38,7 +38,7 @@ Documentation/stable_kernel_rules.txt 的中文翻译 - 没有“理论上的竞争条件”，除非能给出竞争条件如何被利用的解释。 - 不能存在任何的“琐碎的”修正（拼写修正，去掉多余空格之类的）。 - 必须被相关子系统的维护者接受。 - - 必须遵循Documentation/SubmittingPatches里的规则。 + - 必须遵循Documentation/process/submitting-patches.rst里的规则。 向稳定版代码树提交补丁的过程： diff --git a/Documentation/zh_CN/volatile-considered-harmful.txt b/Documentation/zh_CN/volatile-considered-harmful.txt index ba8149d..4751259 100644 --- a/Documentation/zh_CN/volatile-considered-harmful.txt +++ b/Documentation/zh_CN/volatile-considered-harmful.txt @@ -1,4 +1,4 @@ -Chinese translated version of Documentation/volatile-considered-harmful.txt +Chinese translated version of Documentation/process/volatile-considered-harmful.rst If you have any comment or update to the content, please contact the original document maintainer directly. However, if you have a problem @@ -9,7 +9,7 @@ or if there is a problem with the translation. Maintainer: Jonathan Corbet <corbet@lwn.net> Chinese maintainer: Bryan Wu <bryan.wu@analog.com> --------------------------------------------------------------------- -Documentation/volatile-considered-harmful.txt 的中文翻译 +Documentation/process/volatile-considered-harmful.rst 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 diff --git a/MAINTAINERS b/MAINTAINERS index de0451d..69820b7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -35,13 +35,13 @@ trivial patch so apply some common sense. PLEASE check your patch with the automated style checker (scripts/checkpatch.pl) to catch trivial style violations. - See Documentation/CodingStyle for guidance here. + See Documentation/process/coding-style.rst for guidance here. PLEASE CC: the maintainers and mailing lists that are generated by scripts/get_maintainer.pl. The results returned by the script will be best if you have git installed and are making your changes in a branch derived from Linus' latest git tree. - See Documentation/SubmittingPatches for details. + See Documentation/process/submitting-patches.rst for details. PLEASE try to include any credit lines you want added with the patch. It avoids people being missed off by mistake and makes @@ -54,7 +54,7 @@ trivial patch so apply some common sense. of the Linux Foundation certificate of contribution and should include a Signed-off-by: line. The current version of this "Developer's Certificate of Origin" (DCO) is listed in the file - Documentation/SubmittingPatches. + Documentation/process/submitting-patches.rst. 6. Make sure you have the right to send any changes you make. If you do changes at work you may find your employer owns the patch @@ -2924,7 +2924,7 @@ CAPELLA MICROSYSTEMS LIGHT SENSOR DRIVER M: Kevin Tsai <ktsai@capellamicro.com> S: Maintained F: drivers/iio/light/cm* -F: Documentation/devicetree/bindings/i2c/trivial-devices.txt +F: Documentation/devicetree/bindings/i2c/trivial-admin-guide/devices.rst CAVIUM I2C DRIVER M: Jan Glauber <jglauber@cavium.com> @@ -11438,7 +11438,7 @@ STABLE BRANCH M: Greg Kroah-Hartman <gregkh@linuxfoundation.org> L: stable@vger.kernel.org S: Supported -F: Documentation/stable_kernel_rules.txt +F: Documentation/process/stable-kernel-rules.rst STAGING SUBSYSTEM M: Greg Kroah-Hartman <gregkh@linuxfoundation.org> @@ -1,400 +1,18 @@ - Linux kernel release 4.x <http://kernel.org/> +Linux kernel +============ -These are the release notes for Linux version 4. Read them carefully, -as they tell you what this is all about, explain how to install the -kernel, and what to do if something goes wrong. +This file was moved to Documentation/admin-guide/README.rst -WHAT IS LINUX? +Please notice that there are several guides for kernel developers and users. +These guides can be rendered in a number of formats, like HTML and PDF. - Linux is a clone of the operating system Unix, written from scratch by - Linus Torvalds with assistance from a loosely-knit team of hackers across - the Net. It aims towards POSIX and Single UNIX Specification compliance. +In order to build the documentation, use ``make htmldocs`` or +``make pdfdocs``. - It has all the features you would expect in a modern fully-fledged Unix, - including true multitasking, virtual memory, shared libraries, demand - loading, shared copy-on-write executables, proper memory management, - and multistack networking including IPv4 and IPv6. - - It is distributed under the GNU General Public License - see the - accompanying COPYING file for more details. - -ON WHAT HARDWARE DOES IT RUN? - - Although originally developed first for 32-bit x86-based PCs (386 or higher), - today Linux also runs on (at least) the Compaq Alpha AXP, Sun SPARC and - UltraSPARC, Motorola 68000, PowerPC, PowerPC64, ARM, Hitachi SuperH, Cell, - IBM S/390, MIPS, HP PA-RISC, Intel IA-64, DEC VAX, AMD x86-64, AXIS CRIS, - Xtensa, Tilera TILE, AVR32, ARC and Renesas M32R architectures. - - Linux is easily portable to most general-purpose 32- or 64-bit architectures - as long as they have a paged memory management unit (PMMU) and a port of the - GNU C compiler (gcc) (part of The GNU Compiler Collection, GCC). Linux has - also been ported to a number of architectures without a PMMU, although - functionality is then obviously somewhat limited. - Linux has also been ported to itself. You can now run the kernel as a - userspace application - this is called UserMode Linux (UML). - -DOCUMENTATION: - - - There is a lot of documentation available both in electronic form on - the Internet and in books, both Linux-specific and pertaining to - general UNIX questions. I'd recommend looking into the documentation - subdirectories on any Linux FTP site for the LDP (Linux Documentation - Project) books. This README is not meant to be documentation on the - system: there are much better sources available. - - - There are various README files in the Documentation/ subdirectory: - these typically contain kernel-specific installation notes for some - drivers for example. See Documentation/00-INDEX for a list of what - is contained in each file. Please read the Changes file, as it - contains information about the problems, which may result by upgrading - your kernel. - - - The Documentation/DocBook/ subdirectory contains several guides for - kernel developers and users. These guides can be rendered in a - number of formats: PostScript (.ps), PDF, HTML, & man-pages, among others. - After installation, "make psdocs", "make pdfdocs", "make htmldocs", - or "make mandocs" will render the documentation in the requested format. - -INSTALLING the kernel source: - - - If you install the full sources, put the kernel tarball in a - directory where you have permissions (e.g. your home directory) and - unpack it: - - xz -cd linux-4.X.tar.xz | tar xvf - - - Replace "X" with the version number of the latest kernel. - - Do NOT use the /usr/src/linux area! This area has a (usually - incomplete) set of kernel headers that are used by the library header - files. They should match the library, and not get messed up by - whatever the kernel-du-jour happens to be. - - - You can also upgrade between 4.x releases by patching. Patches are - distributed in the xz format. To install by patching, get all the - newer patch files, enter the top level directory of the kernel source - (linux-4.X) and execute: - - xz -cd ../patch-4.x.xz | patch -p1 - - Replace "x" for all versions bigger than the version "X" of your current - source tree, _in_order_, and you should be ok. You may want to remove - the backup files (some-file-name~ or some-file-name.orig), and make sure - that there are no failed patches (some-file-name# or some-file-name.rej). - If there are, either you or I have made a mistake. - - Unlike patches for the 4.x kernels, patches for the 4.x.y kernels - (also known as the -stable kernels) are not incremental but instead apply - directly to the base 4.x kernel. For example, if your base kernel is 4.0 - and you want to apply the 4.0.3 patch, you must not first apply the 4.0.1 - and 4.0.2 patches. Similarly, if you are running kernel version 4.0.2 and - want to jump to 4.0.3, you must first reverse the 4.0.2 patch (that is, - patch -R) _before_ applying the 4.0.3 patch. You can read more on this in - Documentation/applying-patches.txt - - Alternatively, the script patch-kernel can be used to automate this - process. It determines the current kernel version and applies any - patches found. - - linux/scripts/patch-kernel linux - - The first argument in the command above is the location of the - kernel source. Patches are applied from the current directory, but - an alternative directory can be specified as the second argument. - - - Make sure you have no stale .o files and dependencies lying around: - - cd linux - make mrproper - - You should now have the sources correctly installed. - -SOFTWARE REQUIREMENTS - - Compiling and running the 4.x kernels requires up-to-date - versions of various software packages. Consult - Documentation/Changes for the minimum version numbers required - and how to get updates for these packages. Beware that using - excessively old versions of these packages can cause indirect - errors that are very difficult to track down, so don't assume that - you can just update packages when obvious problems arise during - build or operation. - -BUILD directory for the kernel: - - When compiling the kernel, all output files will per default be - stored together with the kernel source code. - Using the option "make O=output/dir" allows you to specify an alternate - place for the output files (including .config). - Example: - - kernel source code: /usr/src/linux-4.X - build directory: /home/name/build/kernel - - To configure and build the kernel, use: - - cd /usr/src/linux-4.X - make O=/home/name/build/kernel menuconfig - make O=/home/name/build/kernel - sudo make O=/home/name/build/kernel modules_install install - - Please note: If the 'O=output/dir' option is used, then it must be - used for all invocations of make. - -CONFIGURING the kernel: - - Do not skip this step even if you are only upgrading one minor - version. New configuration options are added in each release, and - odd problems will turn up if the configuration files are not set up - as expected. If you want to carry your existing configuration to a - new version with minimal work, use "make oldconfig", which will - only ask you for the answers to new questions. - - - Alternative configuration commands are: - - "make config" Plain text interface. - - "make menuconfig" Text based color menus, radiolists & dialogs. - - "make nconfig" Enhanced text based color menus. - - "make xconfig" Qt based configuration tool. - - "make gconfig" GTK+ based configuration tool. - - "make oldconfig" Default all questions based on the contents of - your existing ./.config file and asking about - new config symbols. - - "make silentoldconfig" - Like above, but avoids cluttering the screen - with questions already answered. - Additionally updates the dependencies. - - "make olddefconfig" - Like above, but sets new symbols to their default - values without prompting. - - "make defconfig" Create a ./.config file by using the default - symbol values from either arch/$ARCH/defconfig - or arch/$ARCH/configs/${PLATFORM}_defconfig, - depending on the architecture. - - "make ${PLATFORM}_defconfig" - Create a ./.config file by using the default - symbol values from - arch/$ARCH/configs/${PLATFORM}_defconfig. - Use "make help" to get a list of all available - platforms of your architecture. - - "make allyesconfig" - Create a ./.config file by setting symbol - values to 'y' as much as possible. - - "make allmodconfig" - Create a ./.config file by setting symbol - values to 'm' as much as possible. - - "make allnoconfig" Create a ./.config file by setting symbol - values to 'n' as much as possible. - - "make randconfig" Create a ./.config file by setting symbol - values to random values. - - "make localmodconfig" Create a config based on current config and - loaded modules (lsmod). Disables any module - option that is not needed for the loaded modules. - - To create a localmodconfig for another machine, - store the lsmod of that machine into a file - and pass it in as a LSMOD parameter. - - target$ lsmod > /tmp/mylsmod - target$ scp /tmp/mylsmod host:/tmp - - host$ make LSMOD=/tmp/mylsmod localmodconfig - - The above also works when cross compiling. - - "make localyesconfig" Similar to localmodconfig, except it will convert - all module options to built in (=y) options. - - You can find more information on using the Linux kernel config tools - in Documentation/kbuild/kconfig.txt. - - - NOTES on "make config": - - - Having unnecessary drivers will make the kernel bigger, and can - under some circumstances lead to problems: probing for a - nonexistent controller card may confuse your other controllers - - - A kernel with math-emulation compiled in will still use the - coprocessor if one is present: the math emulation will just - never get used in that case. The kernel will be slightly larger, - but will work on different machines regardless of whether they - have a math coprocessor or not. - - - The "kernel hacking" configuration details usually result in a - bigger or slower kernel (or both), and can even make the kernel - less stable by configuring some routines to actively try to - break bad code to find kernel problems (kmalloc()). Thus you - should probably answer 'n' to the questions for "development", - "experimental", or "debugging" features. - -COMPILING the kernel: - - - Make sure you have at least gcc 3.2 available. - For more information, refer to Documentation/Changes. - - Please note that you can still run a.out user programs with this kernel. - - - Do a "make" to create a compressed kernel image. It is also - possible to do "make install" if you have lilo installed to suit the - kernel makefiles, but you may want to check your particular lilo setup first. - - To do the actual install, you have to be root, but none of the normal - build should require that. Don't take the name of root in vain. - - - If you configured any of the parts of the kernel as `modules', you - will also have to do "make modules_install". - - - Verbose kernel compile/build output: - - Normally, the kernel build system runs in a fairly quiet mode (but not - totally silent). However, sometimes you or other kernel developers need - to see compile, link, or other commands exactly as they are executed. - For this, use "verbose" build mode. This is done by passing - "V=1" to the "make" command, e.g. - - make V=1 all - - To have the build system also tell the reason for the rebuild of each - target, use "V=2". The default is "V=0". - - - Keep a backup kernel handy in case something goes wrong. This is - especially true for the development releases, since each new release - contains new code which has not been debugged. Make sure you keep a - backup of the modules corresponding to that kernel, as well. If you - are installing a new kernel with the same version number as your - working kernel, make a backup of your modules directory before you - do a "make modules_install". - - Alternatively, before compiling, use the kernel config option - "LOCALVERSION" to append a unique suffix to the regular kernel version. - LOCALVERSION can be set in the "General Setup" menu. - - - In order to boot your new kernel, you'll need to copy the kernel - image (e.g. .../linux/arch/x86/boot/bzImage after compilation) - to the place where your regular bootable kernel is found. - - - Booting a kernel directly from a floppy without the assistance of a - bootloader such as LILO, is no longer supported. - - If you boot Linux from the hard drive, chances are you use LILO, which - uses the kernel image as specified in the file /etc/lilo.conf. The - kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or - /boot/bzImage. To use the new kernel, save a copy of the old image - and copy the new image over the old one. Then, you MUST RERUN LILO - to update the loading map! If you don't, you won't be able to boot - the new kernel image. - - Reinstalling LILO is usually a matter of running /sbin/lilo. - You may wish to edit /etc/lilo.conf to specify an entry for your - old kernel image (say, /vmlinux.old) in case the new one does not - work. See the LILO docs for more information. - - After reinstalling LILO, you should be all set. Shutdown the system, - reboot, and enjoy! - - If you ever need to change the default root device, video mode, - ramdisk size, etc. in the kernel image, use the 'rdev' program (or - alternatively the LILO boot options when appropriate). No need to - recompile the kernel to change these parameters. - - - Reboot with the new kernel and enjoy. - -IF SOMETHING GOES WRONG: - - - If you have problems that seem to be due to kernel bugs, please check - the file MAINTAINERS to see if there is a particular person associated - with the part of the kernel that you are having trouble with. If there - isn't anyone listed there, then the second best thing is to mail - them to me (torvalds@linux-foundation.org), and possibly to any other - relevant mailing-list or to the newsgroup. - - - In all bug-reports, *please* tell what kernel you are talking about, - how to duplicate the problem, and what your setup is (use your common - sense). If the problem is new, tell me so, and if the problem is - old, please try to tell me when you first noticed it. - - - If the bug results in a message like - - unable to handle kernel paging request at address C0000010 - Oops: 0002 - EIP: 0010:XXXXXXXX - eax: xxxxxxxx ebx: xxxxxxxx ecx: xxxxxxxx edx: xxxxxxxx - esi: xxxxxxxx edi: xxxxxxxx ebp: xxxxxxxx - ds: xxxx es: xxxx fs: xxxx gs: xxxx - Pid: xx, process nr: xx - xx xx xx xx xx xx xx xx xx xx - - or similar kernel debugging information on your screen or in your - system log, please duplicate it *exactly*. The dump may look - incomprehensible to you, but it does contain information that may - help debugging the problem. The text above the dump is also - important: it tells something about why the kernel dumped code (in - the above example, it's due to a bad kernel pointer). More information - on making sense of the dump is in Documentation/oops-tracing.txt - - - If you compiled the kernel with CONFIG_KALLSYMS you can send the dump - as is, otherwise you will have to use the "ksymoops" program to make - sense of the dump (but compiling with CONFIG_KALLSYMS is usually preferred). - This utility can be downloaded from - ftp://ftp.<country>.kernel.org/pub/linux/utils/kernel/ksymoops/ . - Alternatively, you can do the dump lookup by hand: - - - In debugging dumps like the above, it helps enormously if you can - look up what the EIP value means. The hex value as such doesn't help - me or anybody else very much: it will depend on your particular - kernel setup. What you should do is take the hex value from the EIP - line (ignore the "0010:"), and look it up in the kernel namelist to - see which kernel function contains the offending address. - - To find out the kernel function name, you'll need to find the system - binary associated with the kernel that exhibited the symptom. This is - the file 'linux/vmlinux'. To extract the namelist and match it against - the EIP from the kernel crash, do: - - nm vmlinux | sort | less - - This will give you a list of kernel addresses sorted in ascending - order, from which it is simple to find the function that contains the - offending address. Note that the address given by the kernel - debugging messages will not necessarily match exactly with the - function addresses (in fact, that is very unlikely), so you can't - just 'grep' the list: the list will, however, give you the starting - point of each kernel function, so by looking for the function that - has a starting address lower than the one you are searching for but - is followed by a function with a higher address you will find the one - you want. In fact, it may be a good idea to include a bit of - "context" in your problem report, giving a few lines around the - interesting one. - - If you for some reason cannot do the above (you have a pre-compiled - kernel image or similar), telling me as much about your setup as - possible will help. Please read the REPORTING-BUGS document for details. - - - Alternatively, you can use gdb on a running kernel. (read-only; i.e. you - cannot change values or set break points.) To do this, first compile the - kernel with -g; edit arch/x86/Makefile appropriately, then do a "make - clean". You'll also need to enable CONFIG_PROC_FS (via "make config"). - - After you've rebooted with the new kernel, do "gdb vmlinux /proc/kcore". - You can now use all the usual gdb commands. The command to look up the - point where your system crashed is "l *0xXXXXXXXX". (Replace the XXXes - with the EIP value.) - - gdb'ing a non-running kernel currently fails because gdb (wrongly) - disregards the starting offset for which the kernel is compiled. +There are various text files in the Documentation/ subdirectory, +several of them using the Restructured Text markup notation. +See Documentation/00-INDEX for a list of what is contained in each file. +Please read the Documentation/process/changes.rst file, as it contains the +requirements for building and running the kernel, and information about +the problems which may result by upgrading your kernel. diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index bada636..19d237b 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1525,7 +1525,7 @@ config X86_CHECK_BIOS_CORRUPTION line. By default it scans the low 64k of memory every 60 seconds; see the memory_corruption_check_size and memory_corruption_check_period parameters in - Documentation/kernel-parameters.txt to adjust this. + Documentation/admin-guide/kernel-parameters.rst to adjust this. When enabled with the default parameters, this option has almost no overhead, as it reserves a relatively small amount diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 535e782..c5f9cbe 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -342,7 +342,7 @@ config ACPI_DEBUG Use the acpi.debug_layer and acpi.debug_level kernel command-line parameters documented in Documentation/acpi/debug.txt and - Documentation/kernel-parameters.txt to control the type and + Documentation/admin-guide/kernel-parameters.rst to control the type and amount of debug output. config ACPI_PCI_SLOT diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 223a770..59ce0dd 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -129,7 +129,7 @@ static int ata_force_tbl_size; static char ata_force_param_buf[PAGE_SIZE] __initdata; /* param_buf is thrown away after initialization, disallow read */ module_param_string(force, ata_force_param_buf, sizeof(ata_force_param_buf), 0); -MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/kernel-parameters.txt for details)"); +MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/admin-guide/kernel-parameters.rst for details)"); static int atapi_enabled = 1; module_param(atapi_enabled, int, 0444); diff --git a/drivers/char/pcmcia/cm4000_cs.c b/drivers/char/pcmcia/cm4000_cs.c index c115217..e051fc8 100644 --- a/drivers/char/pcmcia/cm4000_cs.c +++ b/drivers/char/pcmcia/cm4000_cs.c @@ -14,7 +14,7 @@ * (C) 2000,2001,2002,2003,2004 Omnikey AG * * (C) 2005-2006 Harald Welte <laforge@gnumonks.org> - * - Adhere to Kernel CodingStyle + * - Adhere to Kernel process/coding-style.rst * - Port to 2.6.13 "new" style PCMCIA * - Check for copy_{from,to}_user return values * - Use nonseekable_open() @@ -151,7 +151,7 @@ static struct pcmcia_device *dev_table[CM4000_MAX_DEV]; static struct class *cmm_class; /* This table doesn't use spaces after the comma between fields and thus - * violates CodingStyle. However, I don't really think wrapping it around will + * violates process/coding-style.rst. However, I don't really think wrapping it around will * make it any clearer to read -HW */ static unsigned char fi_di_table[10][14] = { /*FI 00 01 02 03 04 05 06 07 08 09 10 11 12 13 */ diff --git a/drivers/net/can/grcan.c b/drivers/net/can/grcan.c index db9538d..a7be12d 100644 --- a/drivers/net/can/grcan.c +++ b/drivers/net/can/grcan.c @@ -15,7 +15,7 @@ * See "Documentation/ABI/testing/sysfs-class-net-grcan" for information on the * sysfs interface. * - * See "Documentation/kernel-parameters.txt" for information on the module + * See "Documentation/admin-guide/kernel-parameters.rst" for information on the module * parameters. * * This program is free software; you can redistribute it and/or modify it diff --git a/drivers/nvdimm/Kconfig b/drivers/nvdimm/Kconfig index 8b2b740..b20ce7d 100644 --- a/drivers/nvdimm/Kconfig +++ b/drivers/nvdimm/Kconfig @@ -28,7 +28,7 @@ config BLK_DEV_PMEM non-standard OEM-specific E820 memory type (type-12, see CONFIG_X86_PMEM_LEGACY), or it is manually specified by the 'memmap=nn[KMG]!ss[KMG]' kernel command line (see - Documentation/kernel-parameters.txt). This driver converts + Documentation/admin-guide/kernel-parameters.rst). This driver converts these persistent memory ranges into block devices that are capable of DAX (direct-access) file system mappings. See Documentation/nvdimm/nvdimm.txt for more details. diff --git a/drivers/staging/vme/devices/vme_user.c b/drivers/staging/vme/devices/vme_user.c index 5dd430f..d84dffb 100644 --- a/drivers/staging/vme/devices/vme_user.c +++ b/drivers/staging/vme/devices/vme_user.c @@ -47,7 +47,7 @@ static const char driver_name[] = "vme_user"; static int bus[VME_USER_BUS_MAX]; static unsigned int bus_num; -/* Currently Documentation/devices.txt defines the following for VME: +/* Currently Documentation/admin-guide/devices.rst defines the following for VME: * * 221 char VME bus * 0 = /dev/bus/vme/m0 First master image diff --git a/drivers/video/fbdev/skeletonfb.c b/drivers/video/fbdev/skeletonfb.c index f948baa1..e219a0a2 100644 --- a/drivers/video/fbdev/skeletonfb.c +++ b/drivers/video/fbdev/skeletonfb.c @@ -836,7 +836,7 @@ static void xxxfb_remove(struct pci_dev *dev) * @dev: PCI device * @msg: the suspend event code. * - * See Documentation/power/devices.txt for more information + * See Documentation/power/admin-guide/devices.rst for more information */ static int xxxfb_suspend(struct pci_dev *dev, pm_message_t msg) { @@ -851,7 +851,7 @@ static int xxxfb_suspend(struct pci_dev *dev, pm_message_t msg) * xxxfb_resume - Optional but recommended function. Resume the device. * @dev: PCI device * - * See Documentation/power/devices.txt for more information + * See Documentation/power/admin-guide/devices.rst for more information */ static int xxxfb_resume(struct pci_dev *dev) { @@ -915,7 +915,7 @@ static void __exit xxxfb_exit(void) * @dev: platform device * @msg: the suspend event code. * - * See Documentation/power/devices.txt for more information + * See Documentation/power/admin-guide/devices.rst for more information */ static int xxxfb_suspend(struct platform_device *dev, pm_message_t msg) { @@ -930,7 +930,7 @@ static int xxxfb_suspend(struct platform_device *dev, pm_message_t msg) * xxxfb_resume - Optional but recommended function. Resume the device. * @dev: platform device * - * See Documentation/power/devices.txt for more information + * See Documentation/power/admin-guide/devices.rst for more information */ static int xxxfb_resume(struct platform_dev *dev) { diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index 7759032..623f723 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -75,7 +75,7 @@ config VIRTIO_MMIO_CMDLINE_DEVICES Allow virtio-mmio devices instantiation via the kernel command line or module parameters. Be aware that using incorrect parameters (base address in particular) can crash your system - you have been warned. - See Documentation/kernel-parameters.txt for details. + See Documentation/admin-guide/kernel-parameters.rst for details. If unsure, say 'N'. diff --git a/fs/Kconfig.binfmt b/fs/Kconfig.binfmt index 4c09d93..b2f82cf 100644 --- a/fs/Kconfig.binfmt +++ b/fs/Kconfig.binfmt @@ -170,8 +170,8 @@ config BINFMT_MISC You can do other nice things, too. Read the file <file:Documentation/binfmt_misc.txt> to learn how to use this - feature, <file:Documentation/java.txt> for information about how - to include Java support. and <file:Documentation/mono.txt> for + feature, <file:Documentation/admin-guide/java.rst> for information about how + to include Java support. and <file:Documentation/admin-guide/mono.rst> for information about how to include Mono-based .NET support. To use binfmt_misc, you will need to mount it: diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig index be40813..b42e5bd 100644 --- a/fs/pstore/Kconfig +++ b/fs/pstore/Kconfig @@ -86,4 +86,4 @@ config PSTORE_RAM Note that for historical reasons, the module will be named "ramoops.ko". - For more information, see Documentation/ramoops.txt. + For more information, see Documentation/admin-guide/ramoops.rst. diff --git a/include/linux/device.h b/include/linux/device.h index bc41e87..36d3a98 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -733,7 +733,7 @@ struct device_dma_parameters { * minimizes board-specific #ifdefs in drivers. * @driver_data: Private pointer for driver specific info. * @power: For device power management. - * See Documentation/power/devices.txt for details. + * See Documentation/power/admin-guide/devices.rst for details. * @pm_domain: Provide callbacks that are executed during system suspend, * hibernation, system resume and during runtime PM transitions * along with subsystem-level and driver-level callbacks. diff --git a/include/linux/pm.h b/include/linux/pm.h index 06eb353..efa67b2 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -258,7 +258,7 @@ typedef struct pm_message { * example, if it detects that a child was unplugged while the system was * asleep). * - * Refer to Documentation/power/devices.txt for more information about the role + * Refer to Documentation/power/admin-guide/devices.rst for more information about the role * of the above callbacks in the system suspend process. * * There also are callbacks related to runtime power management of devices. diff --git a/include/uapi/linux/major.h b/include/uapi/linux/major.h index 620252e..19e195b 100644 --- a/include/uapi/linux/major.h +++ b/include/uapi/linux/major.h @@ -3,7 +3,7 @@ /* * This file has definitions for major device numbers. - * For the device number assignments, see Documentation/devices.txt. + * For the device number assignments, see Documentation/admin-guide/devices.rst. */ #define UNNAMED_MAJOR 0 diff --git a/init/Kconfig b/init/Kconfig index 34407f1..172f80e 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1306,7 +1306,7 @@ config BLK_DEV_INITRD boot loader (loadlin or lilo) and that is mounted as root before the normal boot procedure. It is typically used to load modules needed to mount the "real" root file system, - etc. See <file:Documentation/initrd.txt> for details. + etc. See <file:Documentation/admin-guide/initrd.rst> for details. If RAM disk support (BLK_DEV_RAM) is also included, this also enables initial RAM disk (initrd) support and adds diff --git a/init/main.c b/init/main.c index 2858be7..691eb93 100644 --- a/init/main.c +++ b/init/main.c @@ -980,7 +980,7 @@ static int __ref kernel_init(void *unused) return 0; panic("No working init found. Try passing init= option to kernel. " - "See Linux Documentation/init.txt for guidance."); + "See Linux Documentation/admin-guide/init.rst for guidance."); } static noinline void __init kernel_init_freeable(void) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 33bc56c..d2df3a9 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -13,7 +13,7 @@ config PRINTK_TIME be included, not that the timestamp is recorded. The behavior is also controlled by the kernel command line - parameter printk.time=1. See Documentation/kernel-parameters.txt + parameter printk.time=1. See Documentation/admin-guide/kernel-parameters.rst config MESSAGE_LOGLEVEL_DEFAULT int "Default message log level (1-7)" diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index a8368d1..d0c729c 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -2187,7 +2187,7 @@ sub process { if ($rawline=~/^\+\+\+\s+(\S+)/) { $setup_docs = 0; - if ($1 =~ m@Documentation/kernel-parameters.txt$@) { + if ($1 =~ m@Documentation/admin-guide/kernel-parameters.rst$@) { $setup_docs = 1; } #next; @@ -5102,7 +5102,7 @@ sub process { my $asm_volatile = qr{\b(__asm__|asm)\s+(__volatile__|volatile)\b}; if ($line =~ /\bvolatile\b/ && $line !~ /$asm_volatile/) { WARN("VOLATILE", - "Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt\n" . $herecurr); + "Use of volatile is usually wrong: see Documentation/process/volatile-considered-harmful.rst\n" . $herecurr); } # Check for user-visible strings broken across lines, which breaks the ability @@ -5817,7 +5817,7 @@ sub process { if (!grep(/$name/, @setup_docs)) { CHK("UNDOCUMENTED_SETUP", - "__setup appears un-documented -- check Documentation/kernel-parameters.txt\n" . $herecurr); + "__setup appears un-documented -- check Documentation/admin-guide/kernel-parameters.rst\n" . $herecurr); } } diff --git a/tools/testing/selftests/futex/README b/tools/testing/selftests/futex/README index 0558bb9..f3926c3 100644 --- a/tools/testing/selftests/futex/README +++ b/tools/testing/selftests/futex/README @@ -59,4 +59,4 @@ o FIXME: decide on a sane test naming scheme. Currently the tests are named Coding Style ------------ o The Futex Test project adheres to the coding standards set forth by Linux - kernel as defined in the Linux source Documentation/CodingStyle. + kernel as defined in the Linux source Documentation/process/coding-style.rst. |
