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* kconfig/[mn]conf: shorten title in search-boxYann E. MORIN2013-07-162-4/+4
| | | | | | | | | No need to repeat the 'CONFIG_' string in the title, once is explicit enough. Reported-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Jean Delvare <jdelvare@suse.de>
* kconfig: avoid multiple calls to strlenYann E. MORIN2013-07-161-5/+5
| | | | | | | | | Calls to strlen are costly, so avoid calling strln as much as we can. Reported-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Jean Delvare <jdelvare@suse.de> Reviewed-by: Jean Delvare <jdelvare@suse.de>
* Documentation/kconfig: more concise and straightforward search explanationYann E. MORIN2013-07-161-5/+3
| | | | | | | | | | | | | Re-phrase the explanations on the sorting of search results, in a more concise and complete way. Drop reference to the user's locale when sorting alphabetically, since this is implicit. Reported-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Jean Delvare <jdelvare@suse.de> Reviewed-by: Jean Delvare <jdelvare@suse.de>
* kconfig: allow "hex" and "range" to support longsKees Cook2013-06-291-5/+5
| | | | | | | | | | | The parsing routines for Kconfig files use strtol(), but store and render values as int. Switch types and formating to long to support a wider range of values. For example, 0x80000000 wasn't representable. Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
* Revert "kconfig: fix randomising choice entries in presence of ↵Yann E. MORIN2013-06-261-3/+3
| | | | | | | | | | | | | | | | | | | KCONFIG_ALLCONFIG" This reverts commit 8357b48549e17b3e4e402c7f977b65708922e60f. It breaks more stuff than it fixes. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Signed-off-by: Michal Marek <mmarek@suse.cz>
* kconfig: fix randomising choice entries in presence of KCONFIG_ALLCONFIGYann E. MORIN2013-06-241-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, randconfig does randomise choice entries, unless KCONFIG_ALLCONFIG is specified. For example, given those two files (Thomas' test-case): ---8<--- Config.test.in config OPTIONA bool "Option A" choice prompt "This is a choice" config CHOICE_OPTIONA bool "Choice Option A" config CHOICE_OPTIONB bool "Choice Option B" endchoice config OPTIONB bool "Option B" ---8<--- Config.test.in ---8<--- config.defaults CONFIG_OPTIONA=y ---8<--- config.defaults And running: ./scripts/kconfig/conf --randconfig Config.test.in does properly randomise the two choice symbols (and the two booleans). However, running: KCONFIG_ALLCONFIG=config.defaults \ ./scripts/kconfig/conf --randconfig Config.test.in does *not* reandomise the two choice entries, and only CHOICE_OPTIONA will ever be selected. (OPTIONA will always be set (expected), and OPTIONB will be be properly randomised (expected).) This patch defers setting that a choice has a value until a symbol for that choice is indeed set, so that choices are properly randomised when KCONFIG_ALLCONFIG is set, but not if a symbol for that choice is set. Reported-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Cc: Michal Marek <mmarek@suse.cz> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Stephen Rothwell <sfr@canb.auug.org.au> --- Changes v3 -> v4 - fix previous issue where some choices would not be set, which would cause silentoldconfig to ask for them and was then breaking this workflow (as reported by Arnd and Sedat): KCONFIG_ALLCONFIG=foo.defconfig make randconfig make silentoldconfig </dev/nullo which I have tested (3h28min!) with: touch defconfig for(( i=0; i<10000; i++ )); do KCONFIG_ALLCONFIG=$(pwd)/defconfig make randconfig >/dev/null 2>&1 make silentoldconfig </dev/null >/dev/null 2>&1 || break done which did not break at all. - change done in v3 (below) is already fixed by a previous patch Changes v2 -> v3 - ensure only one symbol is set in a choice Changes v1 -> v2: - further postpone setting that a choice has a value until one is indeed set - do not print symbols that are part of an invisible choice
* kconfig: loop as long as we changed some symbols in randconfigYann E. MORIN2013-06-243-6/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because of choice-in-a-choice constructs, it can happen that not all symbols are assigned a value during randconfig, leading in rare cases to this situation: ---8<--- choice-in-choice.in choice bool "A/B/C" config A bool "A" config B bool "B" if B choice bool "E/F" config E bool "E" config F bool "F" endchoice endif # B config C bool "C" endchoice ---8<--- $ ./scripts/kconfig/conf --randconfig choice-in-choice.in [--SNIP--] $ ./scripts/kconfig/conf --silentoldconfig choice-in-choice.in </dev/null [--SNIP--] A/B/C 1. A (A) > 2. B (B) 3. C (C) choice[1-3]: 2 E/F > 1. E (E) (NEW) 2. F (F) (NEW) choice[1-2]: aborted! Console input/output is redirected. Run 'make oldconfig' to update configuration. Fix this by looping in randconfig for as long as some symbol gets assigned a value. Note: this was spotted with the USB EHCI Debug Device Gadget (USB_G_DBGP), which uses this choice-in-a-choice construct, and exhibits this problem. The example above is just a stripped-down minimalist test-case. Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
* kconfig/[mn]conf: make it explicit in the search box that a regexp is possibleYann E. MORIN2013-06-242-2/+2
| | | | | | | Reported-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Jean Delvare <jdelvare@suse.de> Cc: Michal Marek <mmarek@suse.cz>
* kconfig: sort found symbols by relevanceYann E. MORIN2013-06-242-9/+82
| | | | | | | | | | | | | | | | | | | | | | | | | | | When searching for symbols, return the symbols sorted by relevance. Sorting is done as thus: - first, symbols that match exactly - then, alphabetical sort Since the search can be a regexp, it is possible that more than one symbol matches exactly. In this case, we can't decide which to sort first, so we fallback to alphabeticall sort. Explain this (new!) sorting heuristic in the documentation. Reported-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Cc: Jean Delvare <jdelvare@suse.de> Cc: Michal Marek <mmarek@suse.cz> Cc: Roland Eggner <edvx1@systemanalysen.net> Cc: Wang YanQing <udknight@gmail.com> -- Changes v1->v2: - drop the previous, complex heuristic in favour of a simpler heuristic that is both easier to understand, *and* to maintain (Jean) - explain sorting heuristic in the doc (Jean)
* kconfig/conf: print the seed used to initialise the RNG for randconfigYann E. MORIN2013-06-181-0/+1
| | | | | | ... so the user has a chance to reproduce a test-case. Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
* kconfig/conf: accept a base-16 seed for randconfigYann E. MORIN2013-06-181-1/+1
| | | | Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
* kconfig/conf: fix randconfig setting multiple symbols in a choiceYann E. MORIN2013-06-181-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, randconfig may set more than one symbol in a given choice. Given this config file: config A bool "A" if A choice bool "B/C/D" config B bool "B" config C bool "C" config D bool "D" endchoice endif # A Then randconfig generates such .config files (case where A is not set is not shown below for brevity), and where only the right-most .config is valid: CONFIG_A=y CONFIG_A=y CONFIG_A=y CONFIG_B=y CONFIG_B=y CONFIG_B=y CONFIG_C=y # CONFIG_C is not set # CONFIG_C is not set # CONFIG_D is not set CONFIG_D=y # CONFIG_D is not set That is, in a randomised choice, the first symbol is always selected, and at most one other symbol may be selected. This is due to symbol randomised in a choice not being properly flagged as having a value. Fix that by flagging those symbols adequately: have a user-defined value, and be not valid (to force recalculation of the symbol). Note: if the choice is not conditional, then the randomisation is properly done. Reported-by: Matthieu CASTET <matthieu.castet@parrot.com> Signed-off-by: Matthieu CASTET <matthieu.castet@parrot.com> [yann.morin.1998@free.fr: independently re-done the same patch as Matthieu, as pointed out by Sedat] Cc: Arnaud Lacombe <lacombar@gmail.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
* scripts/config: replace hard-coded script name by a dynamic valueClement Chauplannaz2013-06-181-5/+7
| | | | | | | | | | | | The script `config' prints its name in usage() function. It is currently hard-coded to value `config'. However, the script may be reused under a different name in contexts other than the Linux Kernel. Replace the hard-coded value `config' by the name of the script at runtime. Signed-off-by: Clement Chauplannaz <chauplac@gmail.com> Acked-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
* mconf/nconf: mark empty menus/menuconfigs different from non-empty onesDirk Gouders2013-06-184-13/+31
| | | | | | | | | | | | | | | | | Submenus are sometimes empty and it would be nice if there is something that notifies us that we should not expect any content _before_ we enter a submenu. A new function menu_is_empty() was introduced and empty menus and menuconfigs are now marked by "----" as opposed to non-empty ones that are marked by "--->". This scheme was suggested by "Yann E. MORIN" <yann.morin.1998@free.fr>. Signed-off-by: Dirk Gouders <dirk@gouders.net> Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
* nconf: use function calls instead of ncurses' variables LINES and COLSDirk Gouders2013-06-182-16/+25
| | | | | | | | | | | | | | | | | | | | According to the documentation [1], LINES and COLS are initialized by initscr(); it does not say anything about the behavior when windows are resized. Do not rely on the current implementation of ncurses that updates these variables on resize, but use the propper function calls or macros to get window dimensions. The use of the variables in main() was OK, but for the sake of consistency it was modified to use the macro getmaxyx(). [1] ncurses(3X) Signed-off-by: Dirk Gouders <dirk@gouders.net> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> [yann.morin.1998@free.fr: declare 'lines' and 'columns' on a single line] Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
* mconf: use function calls instead of ncurses' variables LINES and COLSDirk Gouders2013-06-186-14/+19
| | | | | | | | | | | | | | | | | | | | According to the documentation [1], LINES and COLS are initialized by initscr(); it does not say anything about the behavior when windows are resized. Do not rely on the current implementation of ncurses that updates these variables on resize, but use the propper function calls to get window dimensions. init_dialog() could make use of the variables, but for the sake of consistency we do not change it's current use of the macro getmaxyx(). [1] ncurses(3X) Signed-off-by: Dirk Gouders <dirk@gouders.net> Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
* kconfig/lxdialog: handle newline characters in print_autowrap()Dirk Gouders2013-06-182-16/+19
| | | | | | | | | | | | | | | | | | | | When exiting menuconfig with unsaved changes, a dialog like the following is shown: Do you wish to save your new configuration ? <ESC><ESC> to continue. The author of the dialog text specified a newline after the '?', and probably expected it to be processed, so let print_autowrap() handle newlines propperly. Also, reword that dialog's second phrase with a real sentence. Signed-off-by: Dirk Gouders <dirk@gouders.net> Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> [yann.morin.1998@free.fr: very slightly tweak the commit message] Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
* kconfig/lxdialog: Use new mininimum resize definitions in conf_choice()Sedat Dilek2013-06-181-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | This is a cleanup which uses the proper (new) definitions and does not change current behaviour. Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr> --- Yann had some more ideas on improvements: "What would be nice is an improvement that scales the choice window to the number of entries in the choice. If there are a lot of choice entries, then the choice popup grows in height (but does not overflow the screen of course). So, instead of seeing only 6 entries, we'd see as much as possible in the current screen. Ditto for the width: the popup adapts to the longest prompt (but does not overflow the screen either, of course), so prompts are not truncated." NOTE: This patch requires [1]. [1] http://marc.info/?l=linux-kbuild&m=137128726917166&w=2
* kconfig/lxdialog: Add definitions for mininimum (re)size valuesSedat Dilek2013-06-167-9/+23
| | | | | | | | | | | | | | | | | | | | | | Commit c8dc68ad0fbd ("kconfig/lxdialog: support resize") added support for resizing, but forgot to collect all hardcoded values at one single place. Also add a definition for the check for a minimum screen/window size of 80x19. [ ChangeLog v3: * Rename MENU_{HEIGTH,WIDTH}_MIN -> MENUBOX_{HEIGTH,WIDTH}_MIN ChangeLog v2: * Rename WIN_{HEIGTH,WIDTH}_MIN -> WINDOW_{HEIGTH,WIDTH}_MIN * Mention the check for a minimum screen/window size in the changelog * Add a comment above the block of new definitions ] Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com> Acked-by: Wang YanQing <udknight@gmail.com> Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
* kconfig: Fix defconfig when one choice menu selects options that another ↵Arve Hjønnevåg2013-06-164-4/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | choice menu depends on The defconfig and Kconfig combination below, which is based on 3.10-rc4 Kconfigs, resulted in several options getting set to "m" instead of "y". defconfig.choice: ---8<--- CONFIG_MODULES=y CONFIG_USB_ZERO=y ---8<--- Kconfig.choice: ---8<--- menuconfig MODULES bool "Enable loadable module support" config CONFIGFS_FS tristate "Userspace-driven configuration filesystem" config OCFS2_FS tristate "OCFS2 file system support" depends on CONFIGFS_FS select CRC32 config USB_LIBCOMPOSITE tristate select CONFIGFS_FS choice tristate "USB Gadget Drivers" default USB_ETH config USB_ZERO tristate "Gadget Zero (DEVELOPMENT)" select USB_LIBCOMPOSITE config USB_ETH tristate "Ethernet Gadget (with CDC Ethernet support)" select USB_LIBCOMPOSITE endchoice config CRC32 tristate "CRC32/CRC32c functions" default y choice prompt "CRC32 implementation" depends on CRC32 default CRC32_SLICEBY8 config CRC32_SLICEBY8 bool "Slice by 8 bytes" endchoice ---8<--- $ scripts/kconfig/conf --defconfig=defconfig.choice Kconfig.choice would result in: .config: ---8<--- CONFIG_MODULES=y CONFIG_CONFIGFS_FS=m CONFIG_USB_LIBCOMPOSITE=m CONFIG_USB_ZERO=m CONFIG_CRC32=y CONFIG_CRC32_SLICEBY8=y ---8<--- when the expected result would be: .config: ---8<--- CONFIG_MODULES=y CONFIG_CONFIGFS_FS=y CONFIG_USB_LIBCOMPOSITE=y CONFIG_USB_ZERO=y CONFIG_CRC32=y CONFIG_CRC32_SLICEBY8=y ---8<--- Signed-off-by: Arve Hjønnevåg <arve@android.com> [yann.morin.1998@free.fr: add the resulting .config to commit log, remove unneeded USB_GADGET from the defconfig] Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
* Linux 3.10-rc1v3.10-rc1Linus Torvalds2013-05-111-2/+2
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* Merge tag 'trace-fixes-v3.10' of ↵Linus Torvalds2013-05-116-108/+368
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing/kprobes update from Steven Rostedt: "The majority of these changes are from Masami Hiramatsu bringing kprobes up to par with the latest changes to ftrace (multi buffering and the new function probes). He also discovered and fixed some bugs in doing so. When pulling in his patches, I also found a few minor bugs as well and fixed them. This also includes a compile fix for some archs that select the ring buffer but not tracing. I based this off of the last patch you took from me that fixed the merge conflict error, as that was the commit that had all the changes I needed for this set of changes." * tag 'trace-fixes-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/kprobes: Support soft-mode disabling tracing/kprobes: Support ftrace_event_file base multibuffer tracing/kprobes: Pass trace_probe directly from dispatcher tracing/kprobes: Increment probe hit-count even if it is used by perf tracing/kprobes: Use bool for retprobe checker ftrace: Fix function probe when more than one probe is added ftrace: Fix the output of enabled_functions debug file ftrace: Fix locking in register_ftrace_function_probe() tracing: Add helper function trace_create_new_event() to remove duplicate code tracing: Modify soft-mode only if there's no other referrer tracing: Indicate enabled soft-mode in enable file tracing/kprobes: Fix to increment return event probe hit-count ftrace: Cleanup regex_lock and ftrace_lock around hash updating ftrace, kprobes: Fix a deadlock on ftrace_regex_lock ftrace: Have ftrace_regex_write() return either read or error tracing: Return error if register_ftrace_function_probe() fails for event_enable_func() tracing: Don't succeed if event_enable_func did not register anything ring-buffer: Select IRQ_WORK
| * tracing/kprobes: Support soft-mode disablingMasami Hiramatsu2013-05-091-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support soft-mode disabling on kprobe-based dynamic events. Soft-disabling is just ignoring recording if the soft disabled flag is set. Link: http://lkml.kernel.org/r/20130509054454.30398.7237.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing/kprobes: Support ftrace_event_file base multibufferMasami Hiramatsu2013-05-091-36/+214
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support multi-buffer on kprobe-based dynamic events by using ftrace_event_file. Link: http://lkml.kernel.org/r/20130509054449.30398.88343.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing/kprobes: Pass trace_probe directly from dispatcherMasami Hiramatsu2013-05-091-17/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pass the pointer of struct trace_probe directly from probe dispatcher to handlers. This removes redundant container_of macro uses. Same thing has already done in trace_uprobe. Link: http://lkml.kernel.org/r/20130509054441.30398.69112.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing/kprobes: Increment probe hit-count even if it is used by perfMasami Hiramatsu2013-05-091-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Increment probe hit-count for profiling even if it is used by perf tool. Same thing has already done in trace_uprobe. Link: http://lkml.kernel.org/r/20130509054436.30398.21133.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing/kprobes: Use bool for retprobe checkerMasami Hiramatsu2013-05-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Use bool instead of int for kretprobe checker. Link: http://lkml.kernel.org/r/20130509054431.30398.38561.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Fix function probe when more than one probe is addedSteven Rostedt (Red Hat)2013-05-091-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the first function probe is added and the function tracer is updated the functions are modified to call the probe. But when a second function is added, it updates the function records to have the second function also update, but it fails to update the actual function itself. This prevents the second (or third or forth and so on) probes from having their functions called. # echo vfs_symlink:enable_event:sched:sched_switch > set_ftrace_filter # echo vfs_unlink:enable_event:sched:sched_switch > set_ftrace_filter # cat trace # tracer: nop # # entries-in-buffer/entries-written: 0/0 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | # touch /tmp/a # rm /tmp/a # cat trace # tracer: nop # # entries-in-buffer/entries-written: 0/0 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | # ln -s /tmp/a # cat trace # tracer: nop # # entries-in-buffer/entries-written: 414/414 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | <idle>-0 [000] d..3 2847.923031: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=bash next_pid=2786 next_prio=120 <...>-3114 [001] d..4 2847.923035: sched_switch: prev_comm=ln prev_pid=3114 prev_prio=120 prev_state=x ==> next_comm=swapper/1 next_pid=0 next_prio=120 bash-2786 [000] d..3 2847.923535: sched_switch: prev_comm=bash prev_pid=2786 prev_prio=120 prev_state=S ==> next_comm=kworker/0:1 next_pid=34 next_prio=120 kworker/0:1-34 [000] d..3 2847.923552: sched_switch: prev_comm=kworker/0:1 prev_pid=34 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120 <idle>-0 [002] d..3 2847.923554: sched_switch: prev_comm=swapper/2 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=sshd next_pid=2783 next_prio=120 sshd-2783 [002] d..3 2847.923660: sched_switch: prev_comm=sshd prev_pid=2783 prev_prio=120 prev_state=S ==> next_comm=swapper/2 next_pid=0 next_prio=120 Still need to update the functions even though the probe itself does not need to be registered again when added a new probe. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Fix the output of enabled_functions debug fileSteven Rostedt (Red Hat)2013-05-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The enabled_functions debugfs file was created to be able to see what functions have been modified from nops to calling a tracer. The current method uses the counter in the function record. As when a ftrace_ops is registered to a function, its count increases. But that doesn't mean that the function is actively being traced. /proc/sys/kernel/ftrace_enabled can be set to zero which would disable it, as well as something can go wrong and we can think its enabled when only the counter is set. The record's FTRACE_FL_ENABLED flag is set or cleared when its function is modified. That is a much more accurate way of knowing what function is enabled or not. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Fix locking in register_ftrace_function_probe()Steven Rostedt (Red Hat)2013-05-091-4/+6
| | | | | | | | | | | | | | The iteration of the ftrace function list and the call to ftrace_match_record() need to be protected by the ftrace_lock. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Add helper function trace_create_new_event() to remove duplicate codeSteven Rostedt (Red Hat)2013-05-091-12/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Both __trace_add_new_event() and __trace_early_add_new_event() do basically the same thing, except that __trace_add_new_event() does a little more. Instead of having duplicate code between the two functions, add a helper function trace_create_new_event() that both can use. This will help against having bugs fixed in one function but not the other. Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Modify soft-mode only if there's no other referrerMasami Hiramatsu2013-05-092-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modify soft-mode flag only if no other soft-mode referrer (currently only the ftrace triggers) by using a reference counter in each ftrace_event_file. Without this fix, adding and removing several different enable/disable_event triggers on the same event clear soft-mode bit from the ftrace_event_file. This also happens with a typo of glob on setting triggers. e.g. # echo vfs_symlink:enable_event:net:netif_rx > set_ftrace_filter # cat events/net/netif_rx/enable 0* # echo typo_func:enable_event:net:netif_rx > set_ftrace_filter # cat events/net/netif_rx/enable 0 # cat set_ftrace_filter #### all functions enabled #### vfs_symlink:enable_event:net:netif_rx:unlimited As above, we still have a trigger, but soft-mode is gone. Link: http://lkml.kernel.org/r/20130509054429.30398.7464.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: David Sharp <dhsharp@google.com> Cc: Hiraku Toyooka <hiraku.toyooka.gu@hitachi.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Indicate enabled soft-mode in enable fileMasami Hiramatsu2013-05-091-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Indicate enabled soft-mode event as "1*" in "enable" file for each event, because it can be soft-disabled when disable_event trigger is hit. Link: http://lkml.kernel.org/r/20130509054426.30398.28202.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing/kprobes: Fix to increment return event probe hit-countMasami Hiramatsu2013-05-091-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix to increment probe hit-count for function return event. Link: http://lkml.kernel.org/r/20130509054424.30398.34058.stgit@mhiramat-M0-7522 Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Cleanup regex_lock and ftrace_lock around hash updatingMasami Hiramatsu2013-05-091-27/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cleanup regex_lock and ftrace_lock locking points around ftrace_ops hash update code. The new rule is that regex_lock protects ops->*_hash read-update-write code for each ftrace_ops. Usually, hash update is done by following sequence. 1. allocate a new local hash and copy the original hash. 2. update the local hash. 3. move(actually, copy) back the local hash to ftrace_ops. 4. update ftrace entries if needed. 5. release the local hash. This makes regex_lock protect #1-#4, and ftrace_lock to protect #3, #4 and adding and removing ftrace_ops from the ftrace_ops_list. The ftrace_lock protects #3 as well because the move functions update the entries too. Link: http://lkml.kernel.org/r/20130509054421.30398.83411.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace, kprobes: Fix a deadlock on ftrace_regex_lockMasami Hiramatsu2013-05-092-21/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a deadlock on ftrace_regex_lock which happens when setting an enable_event trigger on dynamic kprobe event as below. ---- sh-2.05b# echo p vfs_symlink > kprobe_events sh-2.05b# echo vfs_symlink:enable_event:kprobes:p_vfs_symlink_0 > set_ftrace_filter ============================================= [ INFO: possible recursive locking detected ] 3.9.0+ #35 Not tainted --------------------------------------------- sh/72 is trying to acquire lock: (ftrace_regex_lock){+.+.+.}, at: [<ffffffff810ba6c1>] ftrace_set_hash+0x81/0x1f0 but task is already holding lock: (ftrace_regex_lock){+.+.+.}, at: [<ffffffff810b7cbd>] ftrace_regex_write.isra.29.part.30+0x3d/0x220 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(ftrace_regex_lock); lock(ftrace_regex_lock); *** DEADLOCK *** ---- To fix that, this introduces a finer regex_lock for each ftrace_ops. ftrace_regex_lock is too big of a lock which protects all filter/notrace_hash operations, but it doesn't need to be a global lock after supporting multiple ftrace_ops because each ftrace_ops has its own filter/notrace_hash. Link: http://lkml.kernel.org/r/20130509054417.30398.84254.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> [ Added initialization flag and automate mutex initialization for non ftrace.c ftrace_probes. ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ftrace: Have ftrace_regex_write() return either read or errorSteven Rostedt (Red Hat)2013-05-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | As ftrace_regex_write() reads the result of ftrace_process_regex() which can sometimes return a positive number, only consider a failure if the return is negative. Otherwise, it will skip possible other registered probes and by returning a positive number that wasn't read, it will confuse the user processes doing the writing. Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Return error if register_ftrace_function_probe() fails for ↵Steven Rostedt (Red Hat)2013-05-091-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | event_enable_func() register_ftrace_function_probe() returns the number of functions it registered, which can be zero, it can also return a negative number if something went wrong. But event_enable_func() only checks for the case that it didn't register anything, it needs to also check for the case that something went wrong and return that error code as well. Added some comments about the code as well, to make it more understandable. Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Don't succeed if event_enable_func did not register anythingMasami Hiramatsu2013-05-091-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Return 0 instead of the number of activated ftrace function probes if event_enable_func succeeded and return an error code if it failed or did not register any functions. But it currently returns the number of registered functions and if it didn't register anything, it returns 0, but that is considered success. This also fixes the return value. As if it succeeds, it returns the number of functions that were enabled, which is returned back to the user in ftrace_regex_write (the write() return code). If only one function is enabled, then the return code of the write is one, and this can confuse the user program in thinking it only wrote 1 byte. Link: http://lkml.kernel.org/r/20130509054413.30398.55650.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> [ Rewrote change log to reflect that this fixes two bugs - SR ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * ring-buffer: Select IRQ_WORKSteven Rostedt (Red Hat)2013-05-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the wake up logic for waiters on the buffer has been moved from the tracing code to the ring buffer, it requires also adding IRQ_WORK as the wake up code is performed via irq_work. This fixes compile breakage when a user of the ring buffer is selected but tracing and irq_work are not. Link http://lkml.kernel.org/r/20130503115332.GT8356@rric.localhost Cc: Arnd Bergmann <arnd@arndb.de> Reported-by: Robert Richter <rric@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | Merge tag 'stable/for-linus-3.10-rc0-tag-two' of ↵Linus Torvalds2013-05-115-7/+55
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen bug-fixes from Konrad Rzeszutek Wilk: - More fixes in the vCPU PVHVM hotplug path. - Add more documentation. - Fix various ARM related issues in the Xen generic drivers. - Updates in the xen-pciback driver per Bjorn's updates. - Mask the x2APIC feature for PV guests. * tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pci: Used cached MSI-X capability offset xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST xen: mask x2APIC feature in PV xen: SWIOTLB is only used on x86 xen/spinlock: Fix check from greater than to be also be greater or equal to. xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_info xen/vcpu: Document the xen_vcpu_info and xen_vcpu xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.
| * | xen/pci: Used cached MSI-X capability offsetBjorn Helgaas2013-05-101-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now cache the MSI-X capability offset in the struct pci_dev, so no need to find the capability again. Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASKBjorn Helgaas2013-05-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PCI_MSIX_FLAGS_BIRMASK is mis-named because the BIR mask is in the Table Offset register, not the flags ("Message Control" per spec) register. Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen: clear IRQ_NOAUTOEN and IRQ_NOREQUESTJulien Grall2013-05-081-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reset the IRQ_NOAUTOEN and IRQ_NOREQUEST flags that are enabled by default on ARM. If IRQ_NOAUTOEN is set, __setup_irq doesn't call irq_startup, that is responsible for calling irq_unmask at startup time. As a result event channels remain masked. The clear is already made in bind_evtchn_to_irq with commit a8636c0 but was missing on all others bind_*_to_irq. Move the clear in xen_irq_info_common_init. On x86, IRQ_NOAUTOEN and IRQ_NOREQUEST are cleared by default, so this commit doesn't impact this architecture. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Julien Grall <julien.grall@linaro.org> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen: mask x2APIC feature in PVZhenzhong Duan2013-05-081-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On x2apic enabled pvm, doing sysrq+l, got NULL pointer dereference as below. SysRq : Show backtrace of all active CPUs BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8125e3cb>] memcpy+0xb/0x120 Call Trace: [<ffffffff81039633>] ? __x2apic_send_IPI_mask+0x73/0x160 [<ffffffff8103973e>] x2apic_send_IPI_all+0x1e/0x20 [<ffffffff8103498c>] arch_trigger_all_cpu_backtrace+0x6c/0xb0 [<ffffffff81501be4>] ? _raw_spin_lock_irqsave+0x34/0x50 [<ffffffff8131654e>] sysrq_handle_showallcpus+0xe/0x10 [<ffffffff8131616d>] __handle_sysrq+0x7d/0x140 [<ffffffff81316230>] ? __handle_sysrq+0x140/0x140 [<ffffffff81316287>] write_sysrq_trigger+0x57/0x60 [<ffffffff811ca996>] proc_reg_write+0x86/0xc0 [<ffffffff8116dd8e>] vfs_write+0xce/0x190 [<ffffffff8116e3e5>] sys_write+0x55/0x90 [<ffffffff8150a242>] system_call_fastpath+0x16/0x1b That's because apic points to apic_x2apic_cluster or apic_x2apic_phys but the basic element like cpumask isn't initialized. Mask x2APIC feature in pvm to avoid overwrite of apic pointer, update commit message per Konrad's suggestion. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Tested-by: Tamon Shiose <tamon.shiose@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen: SWIOTLB is only used on x86Arnd Bergmann2013-05-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enabling SWIOTLB_XEN on ARM results in build errors because the underlying SWIOTLB is only available on X86: drivers/xen/swiotlb-xen.c: In function 'is_xen_swiotlb_buffer': drivers/xen/swiotlb-xen.c:105:2: error: implicit declaration of function 'mfn_to_local_pfn Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/spinlock: Fix check from greater than to be also be greater or equal to.Konrad Rzeszutek Wilk2013-05-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During review of git commit cb9c6f15f318aa3aeb62fe525aa5c6dcf6eee159 ("xen/spinlock: Check against default value of -1 for IRQ line.") Stefano pointed out a bug in the patch. Unfortunatly due to vacation timing the fix was not applied and this patch fixes it up. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_infoKonrad Rzeszutek Wilk2013-05-081-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As it will point to some data, but not event channel data (the shared_info has an array limited to 32). This means that for PVHVM guests with more than 32 VCPUs without the usage of VCPUOP_register_info any interrupts to VCPUs larger than 32 would have gone unnoticed during early bootup. That is OK, as during early bootup, in smp_init we end up calling the hotplug mechanism (xen_hvm_cpu_notify) which makes the VCPUOP_register_vcpu_info call for all VCPUs and we can receive interrupts on VCPUs 33 and further. This is just a cleanup. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/vcpu: Document the xen_vcpu_info and xen_vcpuKonrad Rzeszutek Wilk2013-05-071-1/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | They are important structures and it is not clear at first look what they are for. The xen_vcpu is a pointer. By default it points to the shared_info structure (at the CPU offset location). However if the VCPUOP_register_vcpu_info hypercall is implemented we can make the xen_vcpu pointer point to a per-CPU location. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> [v1: Added comments from Ian Campbell] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.Konrad Rzeszutek Wilk2013-05-061-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a user did: echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online we would (this a build with DEBUG enabled) get to: smpboot: ++++++++++++++++++++=_---CPU UP 1 .. snip.. smpboot: Stack at about ffff880074c0ff44 smpboot: CPU1: has booted. and hang. The RCU mechanism would kick in an try to IPI the CPU1 but the IPIs (and all other interrupts) would never arrive at the CPU1. At first glance at least. A bit digging in the hypervisor trace shows that (using xenanalyze): [vla] d4v1 vec 243 injecting 0.043163027 --|x d4v1 intr_window vec 243 src 5(vector) intr f3 ] 0.043163639 --|x d4v1 vmentry cycles 1468 ] 0.043164913 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254 0.043164913 --|x d4v1 inj_virq vec 243 real [vla] d4v1 vec 243 injecting 0.043164913 --|x d4v1 intr_window vec 243 src 5(vector) intr f3 ] 0.043165526 --|x d4v1 vmentry cycles 1472 ] 0.043166800 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254 0.043166800 --|x d4v1 inj_virq vec 243 real [vla] d4v1 vec 243 injecting there is a pending event (subsequent debugging shows it is the IPI from the VCPU0 when smpboot.c on VCPU1 has done "set_cpu_online(smp_processor_id(), true)") and the guest VCPU1 is interrupted with the callback IPI (0xf3 aka 243) which ends up calling __xen_evtchn_do_upcall. The __xen_evtchn_do_upcall seems to do *something* but not acknowledge the pending events. And the moment the guest does a 'cli' (that is the ffffffff81673254 in the log above) the hypervisor is invoked again to inject the IPI (0xf3) to tell the guest it has pending interrupts. This repeats itself forever. The culprit was the per_cpu(xen_vcpu, cpu) pointer. At the bootup we set each per_cpu(xen_vcpu, cpu) to point to the shared_info->vcpu_info[vcpu] but later on use the VCPUOP_register_vcpu_info to register per-CPU structures (xen_vcpu_setup). This is used to allow events for more than 32 VCPUs and for performance optimizations reasons. When the user performs the VCPU hotplug we end up calling the the xen_vcpu_setup once more. We make the hypercall which returns -EINVAL as it does not allow multiple registration calls (and already has re-assigned where the events are being set). We pick the fallback case and set per_cpu(xen_vcpu, cpu) to point to the shared_info->vcpu_info[vcpu] (which is a good fallback during bootup). However the hypervisor is still setting events in the register per-cpu structure (per_cpu(xen_vcpu_info, cpu)). As such when the events are set by the hypervisor (such as timer one), and when we iterate in __xen_evtchn_do_upcall we end up reading stale events from the shared_info->vcpu_info[vcpu] instead of the per_cpu(xen_vcpu_info, cpu) structures. Hence we never acknowledge the events that the hypervisor has set and the hypervisor keeps on reminding us to ack the events which we never do. The fix is simple. Don't on the second time when xen_vcpu_setup is called over-write the per_cpu(xen_vcpu, cpu) if it points to per_cpu(xen_vcpu_info). Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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