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* NOMMU: Make mmap allocation page trimming behaviour configurable.Paul Mundt2009-01-081-0/+14
| | | | | | | | | | | | | | | | | | NOMMU mmap allocates a piece of memory for an mmap that's rounded up in size to the nearest power-of-2 number of pages. Currently it then discards the excess pages back to the page allocator, making that memory available for use by other things. This can, however, cause greater amount of fragmentation. To counter this, a sysctl is added in order to fine-tune the trimming behaviour. The default behaviour remains to trim pages aggressively, while this can either be disabled completely or set to a higher page-granular watermark in order to have finer-grained control. vm region vm_top bits taken from an earlier patch by David Howells. Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Mike Frysinger <vapier.adi@gmail.com>
* NOMMU: Make VMAs per MM as for MMU-mode linuxDavid Howells2009-01-081-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make VMAs per mm_struct as for MMU-mode linux. This solves two problems: (1) In SYSV SHM where nattch for a segment does not reflect the number of shmat's (and forks) done. (2) In mmap() where the VMA's vm_mm is set to point to the parent mm by an exec'ing process when VM_EXECUTABLE is specified, regardless of the fact that a VMA might be shared and already have its vm_mm assigned to another process or a dead process. A new struct (vm_region) is introduced to track a mapped region and to remember the circumstances under which it may be shared and the vm_list_struct structure is discarded as it's no longer required. This patch makes the following additional changes: (1) Regions are now allocated with alloc_pages() rather than kmalloc() and with no recourse to __GFP_COMP, so the pages are not composite. Instead, each page has a reference on it held by the region. Anything else that is interested in such a page will have to get a reference on it to retain it. When the pages are released due to unmapping, each page is passed to put_page() and will be freed when the page usage count reaches zero. (2) Excess pages are trimmed after an allocation as the allocation must be made as a power-of-2 quantity of pages. (3) VMAs are added to the parent MM's R/B tree and mmap lists. As an MM may end up with overlapping VMAs within the tree, the VMA struct address is appended to the sort key. (4) Non-anonymous VMAs are now added to the backing inode's prio list. (5) Holes may be punched in anonymous VMAs with munmap(), releasing parts of the backing region. The VMA and region structs will be split if necessary. (6) sys_shmdt() only releases one attachment to a SYSV IPC shared memory segment instead of all the attachments at that addresss. Multiple shmat()'s return the same address under NOMMU-mode instead of different virtual addresses as under MMU-mode. (7) Core dumping for ELF-FDPIC requires fewer exceptions for NOMMU-mode. (8) /proc/maps is now the global list of mapped regions, and may list bits that aren't actually mapped anywhere. (9) /proc/meminfo gains a line (tagged "MmapCopy") that indicates the amount of RAM currently allocated by mmap to hold mappable regions that can't be mapped directly. These are copies of the backing device or file if not anonymous. These changes make NOMMU mode more similar to MMU mode. The downside is that NOMMU mode requires some extra memory to track things over NOMMU without this patch (VMAs are no longer shared, and there are now region structs). Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Mike Frysinger <vapier.adi@gmail.com> Acked-by: Paul Mundt <lethal@linux-sh.org>
* Merge branch 'sched-fixes-for-linus' of ↵Linus Torvalds2009-01-071-0/+5
|\ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: fix possible recursive rq->lock
| * sched: fix possible recursive rq->lockPeter Zijlstra2009-01-071-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Vaidyanathan Srinivasan reported: > ============================================= > [ INFO: possible recursive locking detected ] > 2.6.28-autotest-tip-sv #1 > --------------------------------------------- > klogd/5062 is trying to acquire lock: > (&rq->lock){++..}, at: [<ffffffff8022aca2>] task_rq_lock+0x45/0x7e > > but task is already holding lock: > (&rq->lock){++..}, at: [<ffffffff805f7354>] schedule+0x158/0xa31 With sched_mc at 2. (it is default-off) Strictly speaking we'll not deadlock, because ttwu will not be able to place the migration task on our rq, but since the code can deal with both rqs getting unlocked, this seems the easiest way out. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'linux-next' of ↵Linus Torvalds2009-01-071-3/+58
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 * 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (98 commits) PCI PM: Put PM callbacks in the order of execution PCI PM: Run default PM callbacks for all devices using new framework PCI PM: Register power state of devices during initialization PCI PM: Call pci_fixup_device from legacy routines PCI PM: Rearrange code in pci-driver.c PCI PM: Avoid touching devices behind bridges in unknown state PCI PM: Move pci_has_legacy_pm_support PCI PM: Power-manage devices without drivers during suspend-resume PCI PM: Add suspend counterpart of pci_reenable_device PCI PM: Fix poweroff and restore callbacks PCI: Use msleep instead of cpu_relax during ASPM link retraining PCI: PCIe portdrv: Add kerneldoc comments to remining core funtions PCI: PCIe portdrv: Rearrange code so that related things are together PCI: PCIe portdrv: Fix suspend and resume of PCI Express port services PCI: PCIe portdrv: Add kerneldoc comments to some core functions x86/PCI: Do not use interrupt links for devices using MSI-X net: sfc: Use pci_clear_master() to disable bus mastering PCI: Add pci_clear_master() as opposite of pci_set_master() PCI hotplug: remove redundant test in cpq hotplug PCI: pciehp: cleanup register and field definitions ...
| * | resource: allow MMIO exclusivity for device driversArjan van de Ven2009-01-071-3/+58
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Device drivers that use pci_request_regions() (and similar APIs) have a reasonable expectation that they are the only ones accessing their device. As part of the e1000e hunt, we were afraid that some userland (X or some bootsplash stuff) was mapping the MMIO region that the driver thought it had exclusively via /dev/mem or via various sysfs resource mappings. This patch adds the option for device drivers to cause their reserved regions to the "banned from /dev/mem use" list, so now both kernel memory and device-exclusive MMIO regions are banned. NOTE: This is only active when CONFIG_STRICT_DEVMEM is set. In addition to the config option, a kernel parameter iomem=relaxed is provided for the cases where developers want to diagnose, in the field, drivers issues from userspace. Reviewed-by: Matthew Wilcox <willy@linux.intel.com> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/arjan/linux-2.6-asyncLinus Torvalds2009-01-074-1/+330
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/arjan/linux-2.6-async: async: don't do the initcall stuff post boot bootchart: improve output based on Dave Jones' feedback async: make the final inode deletion an asynchronous event fastboot: Make libata initialization even more async fastboot: make the libata port scan asynchronous fastboot: make scsi probes asynchronous async: Asynchronous function calls to speed up kernel boot
| * | async: don't do the initcall stuff post bootArjan van de Ven2009-01-071-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | while tracking the asynchronous calls during boot using the initcall_debug convention is useful, doing it once the kernel is done is actually bad now that we use asynchronous operations post boot as well... Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
| * | async: Asynchronous function calls to speed up kernel bootArjan van de Ven2009-01-074-1/+330
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Right now, most of the kernel boot is strictly synchronous, such that various hardware delays are done sequentially. In order to make the kernel boot faster, this patch introduces infrastructure to allow doing some of the initialization steps asynchronously, which will hide significant portions of the hardware delays in practice. In order to not change device order and other similar observables, this patch does NOT do full parallel initialization. Rather, it operates more in the way an out of order CPU does; the work may be done out of order and asynchronous, but the observable effects (instruction retiring for the CPU) are still done in the original sequence. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
* | stop_machine/cpu hotplug: fix disable_nonboot_cpusHeiko Carstens2009-01-071-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | disable_nonboot_cpus calls _cpu_down. But _cpu_down requires that the caller already created the stop_machine workqueue (like cpu_down does). Otherwise a call to stop_machine will lead to accesses to random memory regions. When introducing this new interface (9ea09af3bd3090e8349ca2899ca2011bd94cda85 "stop_machine: introduce stop_machine_create/destroy") I missed the second call site of _cpu_down. So add the missing stop_machine_create/destroy calls to disable_nonboot_cpus as well. Fixes suspend-to-ram/disk and also this bug: [ 286.547348] BUG: unable to handle kernel paging request at 6b6b6b6b [ 286.548940] IP: [<c0150ca4>] __stop_machine+0x88/0xe3 [ 286.550598] Oops: 0002 [#1] SMP [ 286.560580] Pid: 3273, comm: halt Not tainted (2.6.28-06127-g238c6d5 [ 286.560580] EIP: is at __stop_machine+0x88/0xe3 [ 286.560580] Process halt (pid: 3273, ti=f1a28000 task=f4530f30 [ 286.560580] Call Trace: [ 286.560580] [<c03d04e4>] ? _cpu_down+0x10f/0x234 [ 286.560580] [<c012a57e>] ? disable_nonboot_cpus+0x58/0xdc [ 286.560580] [<c01360c0>] ? kernel_poweroff+0x22/0x39 [ 286.560580] [<c0136301>] ? sys_reboot+0xde/0x14c [ 286.560580] [<c01331b2>] ? complete_signal+0x179/0x191 [ 286.560580] [<c0133396>] ? send_signal+0x1cc/0x1e1 [ 286.560580] [<c03de418>] ? _spin_unlock_irqrestore+0x2d/0x3c [ 286.560580] [<c0133b65>] ? group_send_signal_info+0x58/0x61 [ 286.560580] [<c0133b9e>] ? kill_pid_info+0x30/0x3a [ 286.560580] [<c0133d49>] ? sys_kill+0x75/0x13a [ 286.560580] [<c01a06cb>] ? mntput_no_expire+ox1f/0x101 [ 286.560580] [<c019b3b3>] ? dput+0x1e/0x105 [ 286.560580] [<c018ef87>] ? __fput+0x150/0x158 [ 286.560580] [<c0157abf>] ? audit_syscall_entry+0x137/0x159 [ 286.560580] [<c010329f>] ? sysenter_do_call+0x12/0x34 Reported-and-tested-by: "Justin P. Mattock" <justinmattock@gmail.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Tested-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2009-01-073-3/+3
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits) trivial: chack -> check typo fix in main Makefile trivial: Add a space (and a comma) to a printk in 8250 driver trivial: Fix misspelling of "firmware" in docs for ncr53c8xx/sym53c8xx trivial: Fix misspelling of "firmware" in powerpc Makefile trivial: Fix misspelling of "firmware" in usb.c trivial: Fix misspelling of "firmware" in qla1280.c trivial: Fix misspelling of "firmware" in a100u2w.c trivial: Fix misspelling of "firmware" in megaraid.c trivial: Fix misspelling of "firmware" in ql4_mbx.c trivial: Fix misspelling of "firmware" in acpi_memhotplug.c trivial: Fix misspelling of "firmware" in ipw2100.c trivial: Fix misspelling of "firmware" in atmel.c trivial: Fix misspelled firmware in Kconfig trivial: fix an -> a typos in documentation and comments trivial: fix then -> than typos in comments and documentation trivial: update Jesper Juhl CREDITS entry with new email trivial: fix singal -> signal typo trivial: Fix incorrect use of "loose" in event.c trivial: printk: fix indentation of new_text_line declaration trivial: rtc-stk17ta8: fix sparse warning ...
| * trivial: fix then -> than typos in comments and documentationFrederik Schwarzer2009-01-062-2/+2
| | | | | | | | | | | | | | - (better, more, bigger ...) then -> (...) than Signed-off-by: Frederik Schwarzer <schwarzerf@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| * trivial: printk: fix indentation of new_text_line declarationJiri Kosina2009-01-061-1/+1
| | | | | | | | | | | | | | | | Remove bogus indentation of new_text_line declaration introduced in commit ac60ad741. Acked-by: Nick Andrew <nick@nick-andrew.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | Merge branch 'for-linus' of ↵Linus Torvalds2009-01-061-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #3] Revert "CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #2]" SELinux: shrink sizeof av_inhert selinux_class_perm and context CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #2] keys: fix sparse warning by adding __user annotation to cast smack: Add support for unlabeled network hosts and networks selinux: Deprecate and schedule the removal of the the compat_net functionality netlabel: Update kernel configuration API
| * \ Merge branch 'next' into for-linusJames Morris2009-01-071-1/+1
| |\ \ | | |/ | |/|
| | * CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #3]David Howells2009-01-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a regression in cap_capable() due to: commit 3b11a1decef07c19443d24ae926982bc8ec9f4c0 Author: David Howells <dhowells@redhat.com> Date: Fri Nov 14 10:39:26 2008 +1100 CRED: Differentiate objective and effective subjective credentials on a task The problem is that the above patch allows a process to have two sets of credentials, and for the most part uses the subjective credentials when accessing current's creds. There is, however, one exception: cap_capable(), and thus capable(), uses the real/objective credentials of the target task, whether or not it is the current task. Ordinarily this doesn't matter, since usually the two cred pointers in current point to the same set of creds. However, sys_faccessat() makes use of this facility to override the credentials of the calling process to make its test, without affecting the creds as seen from other processes. One of the things sys_faccessat() does is to make an adjustment to the effective capabilities mask, which cap_capable(), as it stands, then ignores. The affected capability check is in generic_permission(): if (!(mask & MAY_EXEC) || execute_ok(inode)) if (capable(CAP_DAC_OVERRIDE)) return 0; This change passes the set of credentials to be tested down into the commoncap and SELinux code. The security functions called by capable() and has_capability() select the appropriate set of credentials from the process being checked. This can be tested by compiling the following program from the XFS testsuite: /* * t_access_root.c - trivial test program to show permission bug. * * Written by Michael Kerrisk - copyright ownership not pursued. * Sourced from: http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-10/6030.html */ #include <limits.h> #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <sys/stat.h> #define UID 500 #define GID 100 #define PERM 0 #define TESTPATH "/tmp/t_access" static void errExit(char *msg) { perror(msg); exit(EXIT_FAILURE); } /* errExit */ static void accessTest(char *file, int mask, char *mstr) { printf("access(%s, %s) returns %d\n", file, mstr, access(file, mask)); } /* accessTest */ int main(int argc, char *argv[]) { int fd, perm, uid, gid; char *testpath; char cmd[PATH_MAX + 20]; testpath = (argc > 1) ? argv[1] : TESTPATH; perm = (argc > 2) ? strtoul(argv[2], NULL, 8) : PERM; uid = (argc > 3) ? atoi(argv[3]) : UID; gid = (argc > 4) ? atoi(argv[4]) : GID; unlink(testpath); fd = open(testpath, O_RDWR | O_CREAT, 0); if (fd == -1) errExit("open"); if (fchown(fd, uid, gid) == -1) errExit("fchown"); if (fchmod(fd, perm) == -1) errExit("fchmod"); close(fd); snprintf(cmd, sizeof(cmd), "ls -l %s", testpath); system(cmd); if (seteuid(uid) == -1) errExit("seteuid"); accessTest(testpath, 0, "0"); accessTest(testpath, R_OK, "R_OK"); accessTest(testpath, W_OK, "W_OK"); accessTest(testpath, X_OK, "X_OK"); accessTest(testpath, R_OK | W_OK, "R_OK | W_OK"); accessTest(testpath, R_OK | X_OK, "R_OK | X_OK"); accessTest(testpath, W_OK | X_OK, "W_OK | X_OK"); accessTest(testpath, R_OK | W_OK | X_OK, "R_OK | W_OK | X_OK"); exit(EXIT_SUCCESS); } /* main */ This can be run against an Ext3 filesystem as well as against an XFS filesystem. If successful, it will show: [root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043 ---------- 1 dhowells dhowells 0 2008-12-31 03:00 /tmp/xxx access(/tmp/xxx, 0) returns 0 access(/tmp/xxx, R_OK) returns 0 access(/tmp/xxx, W_OK) returns 0 access(/tmp/xxx, X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK) returns 0 access(/tmp/xxx, R_OK | X_OK) returns -1 access(/tmp/xxx, W_OK | X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1 If unsuccessful, it will show: [root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043 ---------- 1 dhowells dhowells 0 2008-12-31 02:56 /tmp/xxx access(/tmp/xxx, 0) returns 0 access(/tmp/xxx, R_OK) returns -1 access(/tmp/xxx, W_OK) returns -1 access(/tmp/xxx, X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK) returns -1 access(/tmp/xxx, R_OK | X_OK) returns -1 access(/tmp/xxx, W_OK | X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1 I've also tested the fix with the SELinux and syscalls LTP testsuites. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: J. Bruce Fields <bfields@citi.umich.edu> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
| | * Revert "CRED: Fix regression in cap_capable() as shown up by sys_faccessat() ↵James Morris2009-01-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | [ver #2]" This reverts commit 14eaddc967b16017d4a1a24d2be6c28ecbe06ed8. David has a better version to come.
| | * CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #2]David Howells2009-01-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a regression in cap_capable() due to: commit 5ff7711e635b32f0a1e558227d030c7e45b4a465 Author: David Howells <dhowells@redhat.com> Date: Wed Dec 31 02:52:28 2008 +0000 CRED: Differentiate objective and effective subjective credentials on a task The problem is that the above patch allows a process to have two sets of credentials, and for the most part uses the subjective credentials when accessing current's creds. There is, however, one exception: cap_capable(), and thus capable(), uses the real/objective credentials of the target task, whether or not it is the current task. Ordinarily this doesn't matter, since usually the two cred pointers in current point to the same set of creds. However, sys_faccessat() makes use of this facility to override the credentials of the calling process to make its test, without affecting the creds as seen from other processes. One of the things sys_faccessat() does is to make an adjustment to the effective capabilities mask, which cap_capable(), as it stands, then ignores. The affected capability check is in generic_permission(): if (!(mask & MAY_EXEC) || execute_ok(inode)) if (capable(CAP_DAC_OVERRIDE)) return 0; This change splits capable() from has_capability() down into the commoncap and SELinux code. The capable() security op now only deals with the current process, and uses the current process's subjective creds. A new security op - task_capable() - is introduced that can check any task's objective creds. strictly the capable() security op is superfluous with the presence of the task_capable() op, however it should be faster to call the capable() op since two fewer arguments need be passed down through the various layers. This can be tested by compiling the following program from the XFS testsuite: /* * t_access_root.c - trivial test program to show permission bug. * * Written by Michael Kerrisk - copyright ownership not pursued. * Sourced from: http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-10/6030.html */ #include <limits.h> #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <sys/stat.h> #define UID 500 #define GID 100 #define PERM 0 #define TESTPATH "/tmp/t_access" static void errExit(char *msg) { perror(msg); exit(EXIT_FAILURE); } /* errExit */ static void accessTest(char *file, int mask, char *mstr) { printf("access(%s, %s) returns %d\n", file, mstr, access(file, mask)); } /* accessTest */ int main(int argc, char *argv[]) { int fd, perm, uid, gid; char *testpath; char cmd[PATH_MAX + 20]; testpath = (argc > 1) ? argv[1] : TESTPATH; perm = (argc > 2) ? strtoul(argv[2], NULL, 8) : PERM; uid = (argc > 3) ? atoi(argv[3]) : UID; gid = (argc > 4) ? atoi(argv[4]) : GID; unlink(testpath); fd = open(testpath, O_RDWR | O_CREAT, 0); if (fd == -1) errExit("open"); if (fchown(fd, uid, gid) == -1) errExit("fchown"); if (fchmod(fd, perm) == -1) errExit("fchmod"); close(fd); snprintf(cmd, sizeof(cmd), "ls -l %s", testpath); system(cmd); if (seteuid(uid) == -1) errExit("seteuid"); accessTest(testpath, 0, "0"); accessTest(testpath, R_OK, "R_OK"); accessTest(testpath, W_OK, "W_OK"); accessTest(testpath, X_OK, "X_OK"); accessTest(testpath, R_OK | W_OK, "R_OK | W_OK"); accessTest(testpath, R_OK | X_OK, "R_OK | X_OK"); accessTest(testpath, W_OK | X_OK, "W_OK | X_OK"); accessTest(testpath, R_OK | W_OK | X_OK, "R_OK | W_OK | X_OK"); exit(EXIT_SUCCESS); } /* main */ This can be run against an Ext3 filesystem as well as against an XFS filesystem. If successful, it will show: [root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043 ---------- 1 dhowells dhowells 0 2008-12-31 03:00 /tmp/xxx access(/tmp/xxx, 0) returns 0 access(/tmp/xxx, R_OK) returns 0 access(/tmp/xxx, W_OK) returns 0 access(/tmp/xxx, X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK) returns 0 access(/tmp/xxx, R_OK | X_OK) returns -1 access(/tmp/xxx, W_OK | X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1 If unsuccessful, it will show: [root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043 ---------- 1 dhowells dhowells 0 2008-12-31 02:56 /tmp/xxx access(/tmp/xxx, 0) returns 0 access(/tmp/xxx, R_OK) returns -1 access(/tmp/xxx, W_OK) returns -1 access(/tmp/xxx, X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK) returns -1 access(/tmp/xxx, R_OK | X_OK) returns -1 access(/tmp/xxx, W_OK | X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1 I've also tested the fix with the SELinux and syscalls LTP testsuites. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | Merge branch 'timers-fixes-for-linus' of ↵Linus Torvalds2009-01-061-72/+70
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: hrtimer: splitout peek ahead functionality, fix hrtimer: fixup comments hrtimer: fix recursion deadlock by re-introducing the softirq hrtimer: simplify hotplug migration hrtimer: fix HOTPLUG_CPU=n compile warning hrtimer: splitout peek ahead functionality
| * | | hrtimer: splitout peek ahead functionality, fixIngo Molnar2009-01-051-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: build fix on !CONFIG_HIGH_RES_TIMERS Fix: kernel/hrtimer.c:1586: error: implicit declaration of function '__hrtimer_peek_ahead_timers' Signen-off-by: Ingo Molnar <mingo@elte.hu>
| * | | hrtimer: fixup commentsThomas Gleixner2009-01-051-11/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clean up the comments Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | hrtimer: fix recursion deadlock by re-introducing the softirqPeter Zijlstra2009-01-051-33/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix rare runtime deadlock There are a few sites that do: spin_lock_irq(&foo) hrtimer_start(&bar) __run_hrtimer(&bar) func() spin_lock(&foo) which obviously deadlocks. In order to avoid this, never call __run_hrtimer() from hrtimer_start*() context, but instead defer this to softirq context. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | hrtimer: simplify hotplug migrationThomas Gleixner2009-01-051-15/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup No need for a smp function call, which is likely to run on the same CPU anyway. We can just call hrtimers_peek_ahead() in the interrupts disabled section of migrate_hrtimers(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | hrtimer: fix HOTPLUG_CPU=n compile warningThomas Gleixner2009-01-051-11/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup kernel/hrtimer.c: In function 'hrtimer_cpu_notify': kernel/hrtimer.c:1574: warning: unused variable 'dcpu' Introduced by commit 37810659ea7d9572c5ac284ade272f806ef8f788 ("hrtimer: removing all ur callback modes, fix hotplug") from the timers. dcpu is only used if CONFIG_HOTPLUG_CPU is set. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | hrtimer: splitout peek ahead functionalityThomas Gleixner2009-01-051-7/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup Provide a peek ahead function that assumes irqs disabled, allows for micro optimizations. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | Merge branch 'sched-fixes-for-linus' of ↵Linus Torvalds2009-01-066-33/+31
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: fix section mismatch sched: fix double kfree in failure path sched: clean up arch_reinit_sched_domains() sched: mark sched_create_sysfs_power_savings_entries() as __init getrusage: RUSAGE_THREAD should return ru_utime and ru_stime sched: fix sched_slice() sched_clock: prevent scd->clock from moving backwards, take #2 sched: sched.c declare variables before they get used
| * | | | sched: fix section mismatchLi Zefan2009-01-062-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | init_rootdomain() calls alloc_bootmem_cpumask_var() at system boot, so does cpupri_init(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | sched: fix double kfree in failure pathLi Zefan2009-01-061-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's not the responsibility of init_rootdomain() to free root_domain allocated by alloc_rootdomain(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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| *---. \ \ \ Merge branches 'sched/clock', 'sched/cleanups' and 'linus' into sched/urgentIngo Molnar2009-01-066-30/+103
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| | * | | | | sched_clock: prevent scd->clock from moving backwards, take #2Thomas Gleixner2008-12-312-3/+9
| | | |_|_|/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Redo: 5b7dba4: sched_clock: prevent scd->clock from moving backwards which had to be reverted due to s2ram hangs: ca7e716: Revert "sched_clock: prevent scd->clock from moving backwards" ... this time with resume restoring GTOD later in the sequence taken into account as well. The "timekeeping_suspended" flag is not very nice but we cannot call into GTOD before it has been properly resumed and the scheduler will run very early in the resume sequence. Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | sched: clean up arch_reinit_sched_domains()Li Zefan2009-01-051-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Make arch_reinit_sched_domains() static. It was exported to be used in s390, but now rebuild_sched_domains() is used instead. - Make it return void. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | sched: mark sched_create_sysfs_power_savings_entries() as __initLi Zefan2009-01-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup The only caller is cpu_dev_init() which is marked as __init. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | Merge branch 'linus' into sched/urgentIngo Molnar2009-01-0545-1577/+1718
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| * | | | | getrusage: RUSAGE_THREAD should return ru_utime and ru_stimeKOSAKI Motohiro2009-01-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: task stats regression fix Original getrusage(RUSAGE_THREAD) implementation can return ru_utime and ru_stime. But commit "f06febc: timers: fix itimer/many thread hang" broke it. this patch restores it. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Roland McGrath <roland@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | sched: fix sched_slice()Mike Galbraith2009-01-021-18/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix bad-interactivity buglet Fix sched_slice() to emit a sane result whether a task is currently enqueued or not. Signed-off-by: Mike Galbraith <efault@gmx.de> Tested-by: Jayson King <dev@jaysonking.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> kernel/sched_fair.c | 30 ++++++++++++------------------ 1 file changed, 12 insertions(+), 18 deletions(-)
* | | | | | Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds2009-01-065-53/+72
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rcu: fix rcutorture bug rcu: eliminate synchronize_rcu_xxx macro rcu: make treercu safe for suspend and resume rcu: fix rcutree grace-period-latency bug on small systems futex: catch certain assymetric (get|put)_futex_key calls futex: make futex_(get|put)_key() calls symmetric locking, percpu counters: introduce separate lock classes swiotlb: clean up EXPORT_SYMBOL usage swiotlb: remove unnecessary declaration swiotlb: replace architecture-specific swiotlb.h with linux/swiotlb.h swiotlb: add support for systems with highmem swiotlb: store phys address in io_tlb_orig_addr array swiotlb: add hwdev to swiotlb_phys_to_bus() / swiotlb_sg_to_bus()
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| *---. \ \ \ \ \ Merge branches 'core/futexes', 'core/locking', 'core/rcu' and 'linus' into ↵Ingo Molnar2009-01-0610-679/+596
| |\ \ \ \ \ \ \ \ | | | | | |_|_|_|/ | | | | |/| | | | | | | | | | | | | core/urgent
| | * | | | | | | futex: catch certain assymetric (get|put)_futex_key callsDarren Hart2009-01-021-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: add debug check Following up on my previous key reference accounting patches, this patch will catch puts on keys that haven't been "got". This won't catch nested get/put mismatches though. Build and boot tested, with minimal desktop activity and a run of the open_posix_testsuite in LTP for testing. No warnings logged. Signed-off-by: Darren Hart <dvhltc@us.ibm.com> Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | | | futex: make futex_(get|put)_key() calls symmetricDarren Hart2008-12-301-31/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup This patch makes the calls to futex_get_key_refs() and futex_drop_key_refs() explicitly symmetric by only "putting" keys we successfully "got". Also cleanup a couple return points that didn't "put" after a successful "get". Build and boot tested on an x86_64 system. Signed-off-by: Darren Hart <dvhltc@us.ibm.com> Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | rcu: fix rcutorture bugPaul E. McKenney2009-01-051-10/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix an rcutorture bug that prevents the shutdown notifier from ever actually having any effect, due to the fact that kthreads ignore all signals. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | rcu: eliminate synchronize_rcu_xxx macroPaul E. McKenney2009-01-052-3/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup Expand macro into two files. The synchronize_rcu_xxx macro is quite ugly and it's only used by two callers, so expand it instead. This makes this code easier to change. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | rcu: make treercu safe for suspend and resumePaul E. McKenney2009-01-051-8/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix kernel warnings [and potential crash] during suspend+resume Kudos to both Dhaval Giani and Jens Axboe for finding a bug in treercu that causes warnings after suspend-resume cycles in Dhaval's case and during stress tests in Jens's case. It would also probably cause failures if heavily stressed. The solution, ironically enough, is to revert to rcupreempt's code for initializing the dynticks state. And the patch even results in smaller code -- so what was I thinking??? This is 2.6.29 material, given that people really do suspend and resume Linux these days. ;-) Reported-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Reported-by: Jens Axboe <jens.axboe@oracle.com> Tested-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Tested-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | rcu: fix rcutree grace-period-latency bug on small systemsPaul E. McKenney2009-01-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix delays during bootup Kudos to Andi Kleen for finding a grace-period-latency problem! The problem was that the special-case code for small machines never updated the ->signaled field to indicate that grace-period initialization had completed, which prevented force_quiescent_state() from ever expediting grace periods. This problem resulted in grace periods extending for more than 20 seconds. Not subtle. I introduced this bug during my inspection process when I fixed a race between grace-period initialization and force_quiescent_state() execution. The following patch properly updates the ->signaled field for the "small"-system case (no more than 32 CPUs for 32-bit kernels and no more than 64 CPUs for 64-bit kernels). Reported-by: Andi Kleen <andi@firstfloor.org> Tested-by: Andi Kleen <andi@firstfloor.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | | | | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6Linus Torvalds2009-01-062-5/+5
|\ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (60 commits) uio: make uio_info's name and version const UIO: Documentation for UIO ioport info handling UIO: Pass information about ioports to userspace (V2) UIO: uio_pdrv_genirq: allow custom irq_flags UIO: use pci_ioremap_bar() in drivers/uio arm: struct device - replace bus_id with dev_name(), dev_set_name() libata: struct device - replace bus_id with dev_name(), dev_set_name() avr: struct device - replace bus_id with dev_name(), dev_set_name() block: struct device - replace bus_id with dev_name(), dev_set_name() chris: struct device - replace bus_id with dev_name(), dev_set_name() dmi: struct device - replace bus_id with dev_name(), dev_set_name() gadget: struct device - replace bus_id with dev_name(), dev_set_name() gpio: struct device - replace bus_id with dev_name(), dev_set_name() gpu: struct device - replace bus_id with dev_name(), dev_set_name() hwmon: struct device - replace bus_id with dev_name(), dev_set_name() i2o: struct device - replace bus_id with dev_name(), dev_set_name() IA64: struct device - replace bus_id with dev_name(), dev_set_name() i7300_idle: struct device - replace bus_id with dev_name(), dev_set_name() infiniband: struct device - replace bus_id with dev_name(), dev_set_name() ISDN: struct device - replace bus_id with dev_name(), dev_set_name() ...
| * | | | | | | | | pm: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers2009-01-061-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | | | | | | | kernel/ksysfs.c:fix dependence on CONFIG_NETMing Lei2009-01-061-2/+2
| | |_|_|/ / / / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Access to uevent_seqnum and uevent_helper does not need to depend on CONFIG_NET, so remove it. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | | | | | | | | dma-coherent: catch oversized requests to dma_alloc_from_coherent()Johannes Weiner2009-01-061-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prevent passing an order to bitmap_find_free_region() that is larger than the actual bitmap can represent. These requests can come from device drivers that have no idea how big the dma region is and need to rely on dma_alloc_from_coherent() to sort it out for them. Reported-by: Guennadi Liakhovetski <lg@denx.de> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Dmitry Baryshkov <dbaryshkov@gmail.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | | dma_alloc_coherent: clean it upAndrew Morton2009-01-061-25/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This thing was rather stupidly coded. Rework it all prior to making changes. Also, rename local variable `page': kernel readers expect something called `page' to have type `struct page *'. Cc: Guennadi Liakhovetski <lg@denx.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Dmitry Baryshkov <dbaryshkov@gmail.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | | dma_alloc_from_coherent(): fix fallback to generic memoryAndrew Morton2009-01-061-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If bitmap_find_free_region() fails and DMA_MEMORY_EXCLUSIVE is not set, the function will fail to write anything to *ret and will return 1. This will cause dma_alloc_coherent() to return an uninitialised value, crashing the kernel, perhaps via DMA to a random address. Fix that by changing it to return zero in this case, so the caller will proceed to allocate the memory from the generic memory allocator. Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Dmitry Baryshkov <dbaryshkov@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | | coredump_filter: permit changing of the default filterHidehiro Kawai2009-01-061-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce a new kernel parameter `coredump_filter'. Setting a value to this parameter causes the default bitmask of coredump_filter to be changed. It is useful for users to change coredump_filter settings for the whole system at boot time. Without this parameter, users have to change coredump_filter settings for each /proc/<pid>/ in an initializing script. Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Roland McGrath <roland@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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