aboutsummaryrefslogtreecommitdiffstats
path: root/mm/kmemleak.c
Commit message (Collapse)AuthorAge
* kmemleak: use rbtree instead of prio treeMichel Lespinasse2012-10-09
| | | | | | | | | | | | | | | | | | | | | | kmemleak uses a tree where each node represents an allocated memory object in order to quickly find out what object a given address is part of. However, the objects don't overlap, so rbtrees are a better choice than prio tree for this use. They are both faster and have lower memory overhead. Tested by booting a kernel with kmemleak enabled, loading the kmemleak_test module, and looking for the expected messages. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kmemleak: Replace list_for_each_continue_rcu with new interfaceMichael Wang2012-09-23
| | | | | | | | | | | This patch replaces list_for_each_continue_rcu() with list_for_each_entry_continue_rcu() to save a few lines of code and allow removing list_for_each_continue_rcu(). Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
* kmemleak: Disable early logging when kmemleak is off by defaultCatalin Marinas2012-01-20
| | | | | | | | | | | | | | | Commit b6693005 (kmemleak: When the early log buffer is exceeded, report the actual number) deferred the disabling of the early logging to kmemleak_init(). However, when CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF=y, the early logging was no longer disabled causing __init kmemleak functions to be called even after the kernel freed the init memory. This patch disables the early logging during kmemleak_init() if kmemleak is left disabled. Reported-by: Dirk Gouders <gouders@et.bocholt.fh-gelsenkirchen.de> Tested-by: Dirk Gouders <gouders@et.bocholt.fh-gelsenkirchen.de> Tested-by: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Only scan non-zero-size areasTiejun Chen2012-01-20
| | | | | | | | | Kmemleak should only track valid scan areas with a non-zero size. Otherwise, such area may reside just at the end of an object and kmemleak would report "Adding scan area to unknown object". Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Add support for memory hotplugLaura Abbott2011-12-02
| | | | | | | | | Ensure that memory hotplug can co-exist with kmemleak by taking the hotplug lock before scanning the memory banks. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Handle percpu memory allocationCatalin Marinas2011-12-02
| | | | | | | | | | | | | This patch adds kmemleak callbacks from the percpu allocator, reducing a number of false positives caused by kmemleak not scanning such memory blocks. The percpu chunks are never reported as leaks because of current kmemleak limitations with the __percpu pointer not pointing directly to the actual chunks. Reported-by: Huajun Li <huajun.li.lee@gmail.com> Acked-by: Christoph Lameter <cl@gentwo.org> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Report previously found leaks even after an errorCatalin Marinas2011-12-02
| | | | | | | | | | If an error fatal to kmemleak (like memory allocation failure) happens, kmemleak disables itself but it also removes the access to any previously found memory leaks. This patch allows read-only access to the kmemleak debugfs interface but disables any other action. Reported-by: Nick Bowler <nbowler@elliptictech.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: When the early log buffer is exceeded, report the actual numberCatalin Marinas2011-12-02
| | | | | | | | | Just telling that the early log buffer has been exceeded doesn't mean much. This patch moves the error printing to the kmemleak_init() function and displays the actual calls to the kmemleak API during early logging. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Show where early_log issues come fromCatalin Marinas2011-12-02
| | | | | | | | | | | | | | | | | | Based on initial patch by Steven Rostedt. Early kmemleak warnings did not show where the actual kmemleak API had been called from but rather just a backtrace to the kmemleak_init() function. By having all early kmemleak logs record the stack_trace, we can have kmemleak_init() write exactly where the problem occurred. This patch adds the setting of the kmemleak_warning variable every time a kmemleak warning is issued. The kmemleak_init() function checks this variable during early log replaying and prints the log trace if there was any warning. Reported-by: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@google.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org>
* mm: Map most files to use export.h instead of module.hPaul Gortmaker2011-10-31
| | | | | | | | The files changed within are only using the EXPORT_SYMBOL macro variants. They are not using core modular infrastructure and hence don't need module.h but only the export.h header. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* atomic: use <linux/atomic.h>Arun Sharma2011-07-26
| | | | | | | | | | | | | | This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kmemleak: Do not return a pointer to an object that kmemleak did not getCatalin Marinas2011-05-19
| | | | | | | | | | | | | The kmemleak_seq_next() function tries to get an object (and increment its use count) before returning it. If it could not get the last object during list traversal (because it may have been freed), the function should return NULL rather than a pointer to such object that it did not get. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Phil Carmody <ext-phil.2.carmody@nokia.com> Acked-by: Phil Carmody <ext-phil.2.carmody@nokia.com> Cc: <stable@kernel.org>
* Fix common misspellingsLucas De Marchi2011-03-31
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* kmemleak: Allow kmemleak metadata allocations to failCatalin Marinas2011-01-27
| | | | | | | | | | | | | | This patch adds __GFP_NORETRY and __GFP_NOMEMALLOC flags to the kmemleak metadata allocations so that it has a smaller effect on the users of the kernel slab allocator. Since kmemleak allocations can now fail more often, this patch also reduces the verbosity by passing __GFP_NOWARN and not dumping the stack trace when a kmemleak allocation fails. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Toralf Förster <toralf.foerster@gmx.de> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: David Rientjes <rientjes@google.com> Cc: Ted Ts'o <tytso@mit.edu>
* kmemleak: Fix typo in the commentHolger Hans Peter Freyther2010-08-08
| | | | | | | Fix typo in comment. Signed-off-by: Holger Hans Peter Freyther <zecke@selfish.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Add DocBook style comments to kmemleak.cCatalin Marinas2010-07-19
| | | | | | | | The description and parameters of the kmemleak API weren't obvious. This patch adds comments clarifying the API usage. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
* kmemleak: Introduce a default off mode for kmemleakJason Baron2010-07-19
| | | | | | | | | | | Introduce a new DEBUG_KMEMLEAK_DEFAULT_OFF config parameter that allows kmemleak to be disabled by default, but enabled on the command line via: kmemleak=on. Although a reboot is required to turn it on, its still useful to not require a re-compile. Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
* kmemleak: Show more information for objects found by aliasCatalin Marinas2010-07-19
| | | | | | | | | There may be situations when an object is freed using a pointer inside the memory block. Kmemleak should show more information to help with debugging. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* Merge branch 'kmemleak' of git://linux-arm.org/linux-2.6Linus Torvalds2009-12-17
|\ | | | | | | | | | | | | | | | | | | | | * 'kmemleak' of git://linux-arm.org/linux-2.6: kmemleak: fix kconfig for crc32 build error kmemleak: Reduce the false positives by checking for modified objects kmemleak: Show the age of an unreferenced object kmemleak: Release the object lock before calling put_object() kmemleak: Scan the _ftrace_events section in modules kmemleak: Simplify the kmemleak_scan_area() function prototype kmemleak: Do not use off-slab management with SLAB_NOLEAKTRACE
| * kmemleak: Reduce the false positives by checking for modified objectsCatalin Marinas2009-10-28
| | | | | | | | | | | | | | | | | | | | | | | | | | If an object was modified since it was previously suspected as leak, do not report it. The modification check is done by calculating the checksum (CRC32) of such object. Several false positives are caused by objects being removed from linked lists (e.g. allocation pools) and temporarily breaking the reference chain since kmemleak runs concurrently with such list mutation primitives. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * kmemleak: Show the age of an unreferenced objectCatalin Marinas2009-10-28
| | | | | | | | | | | | | | | | The jiffies shown for unreferenced objects isn't always meaningful to people debugging kernel memory leaks. This patch adds the age as well to the displayed information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * kmemleak: Release the object lock before calling put_object()Catalin Marinas2009-10-28
| | | | | | | | | | | | | | | | The put_object() function may free the object if the use_count dropped to 0. There shouldn't be further accesses to such object unless it is known that the use_count is non-zero. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * kmemleak: Simplify the kmemleak_scan_area() function prototypeCatalin Marinas2009-10-28
| | | | | | | | | | | | | | | | | | | | This function was taking non-necessary arguments which can be determined by kmemleak. The patch also modifies the calling sites. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au>
* | tree-wide: fix typos "aquire" -> "acquire", "cumsumed" -> "consumed"Uwe Kleine-König2009-11-09
|/ | | | | | | | | | | This patch was generated by git grep -E -i -l '[Aa]quire' | xargs -r perl -p -i -e 's/([Aa])quire/$1cquire/' and the cumsumed was found by checking the diff for aquire. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* kmemleak: Check for NULL pointer returned by create_object()Catalin Marinas2009-10-09
| | | | | | | | | | This patch adds NULL pointer checking in the early_alloc() function. Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kmemleak: Use GFP_ATOMIC for early_alloc().Tetsuo Handa2009-10-09
| | | | | | | | We can't use GFP_KERNEL inside rcu_read_lock(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kmemleak: Improve the "Early log buffer exceeded" error messageCatalin Marinas2009-09-11
| | | | | | | | Based on a suggestion from Jaswinder, clarify what the user would need to do to avoid this error message from kmemleak. Reported-by: Jaswinder Singh Rajput <jaswinder@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: fix sparse warning for static declarationsLuis R. Rodriguez2009-09-08
| | | | | | | | | | | This fixes these sparse warnings: mm/kmemleak.c:1179:6: warning: symbol 'start_scan_thread' was not declared. Should it be static? mm/kmemleak.c:1194:6: warning: symbol 'stop_scan_thread' was not declared. Should it be static? Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: fix sparse warning over overshadowed flagsLuis R. Rodriguez2009-09-08
| | | | | | | | | | | | | A secondary irq_save is not required as a locking before it was already disabling irqs. This fixes this sparse warning: mm/kmemleak.c:512:31: warning: symbol 'flags' shadows an earlier one mm/kmemleak.c:448:23: originally declared here Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: move common painting code togetherLuis R. Rodriguez2009-09-08
| | | | | | | | | | When painting grey or black we do the same thing, bring this together into a helper and identify coloring grey or black explicitly with defines. This makes this a little easier to read. Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: add clear command supportLuis R. Rodriguez2009-09-08
| | | | | | | | | | | | | | | | | | | | | | | | In an ideal world your kmemleak output will be small, when its not (usually during initial bootup) you can use the clear command to ingore previously reported and unreferenced kmemleak objects. We do this by painting all currently reported unreferenced objects grey. We paint them grey instead of black to allow future scans on the same objects as such objects could still potentially reference newly allocated objects in the future. To test a critical section on demand with a clean /sys/kernel/debug/kmemleak you can do: echo clear > /sys/kernel/debug/kmemleak test your kernel or modules echo scan > /sys/kernel/debug/kmemleak Then as usual to get your report with: cat /sys/kernel/debug/kmemleak Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: use bool for true/false questionsLuis R. Rodriguez2009-09-08
| | | | | | Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Do no create the clean-up thread during kmemleak_disable()Catalin Marinas2009-09-08
| | | | | | | | | | | The kmemleak_disable() function could be called from various contexts including IRQ. It creates a clean-up thread but the kthread_create() function has restrictions on which contexts it can be called from, mainly because of the kthread_create_lock. The patch changes the kmemleak clean-up thread to a workqueue. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Eric Paris <eparis@redhat.com>
* kmemleak: Scan all thread stacksCatalin Marinas2009-09-04
| | | | | | | This patch changes the for_each_process() loop with the do_each_thread()/while_each_thread() pair. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Don't scan uninitialized memory when kmemcheck is enabledPekka Enberg2009-09-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ingo Molnar reported the following kmemcheck warning when running both kmemleak and kmemcheck enabled: PM: Adding info for No Bus:vcsa7 WARNING: kmemcheck: Caught 32-bit read from uninitialized memory (f6f6e1a4) d873f9f600000000c42ae4c1005c87f70000000070665f666978656400000000 i i i i u u u u i i i i i i i i i i i i i i i i i i i i i u u u ^ Pid: 3091, comm: kmemleak Not tainted (2.6.31-rc7-tip #1303) P4DC6 EIP: 0060:[<c110301f>] EFLAGS: 00010006 CPU: 0 EIP is at scan_block+0x3f/0xe0 EAX: f40bd700 EBX: f40bd780 ECX: f16b46c0 EDX: 00000001 ESI: f6f6e1a4 EDI: 00000000 EBP: f10f3f4c ESP: c2605fcc DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 CR0: 8005003b CR2: e89a4844 CR3: 30ff1000 CR4: 000006f0 DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 DR6: ffff4ff0 DR7: 00000400 [<c110313c>] scan_object+0x7c/0xf0 [<c1103389>] kmemleak_scan+0x1d9/0x400 [<c1103a3c>] kmemleak_scan_thread+0x4c/0xb0 [<c10819d4>] kthread+0x74/0x80 [<c10257db>] kernel_thread_helper+0x7/0x3c [<ffffffff>] 0xffffffff kmemleak: 515 new suspected memory leaks (see /sys/kernel/debug/kmemleak) kmemleak: 42 new suspected memory leaks (see /sys/kernel/debug/kmemleak) The problem here is that kmemleak will scan partially initialized objects that makes kmemcheck complain. Fix that up by skipping uninitialized memory regions when kmemcheck is enabled. Reported-by: Ingo Molnar <mingo@elte.hu> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
* kmemleak: Printing of the objects hex dumpSergey Senozhatsky2009-08-27
| | | | | | | | | | | | Introducing printing of the objects hex dump to the seq file. The number of lines to be printed is limited to HEX_MAX_LINES to prevent seq file spamming. The actual number of printed bytes is less than or equal to (HEX_MAX_LINES * HEX_ROW_SIZE). (slight adjustments by Catalin Marinas) Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@mail.by> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Save the stack trace for early allocationsCatalin Marinas2009-08-27
| | | | | | | | | | Before slab is initialised, kmemleak save the allocations in an early log buffer. They are later recorded as normal memory allocations. This patch adds the stack trace saving to the early log buffer, otherwise the information shown for such objects only refers to the kmemleak_init() function. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Mark the early log buffer as __initdataCatalin Marinas2009-08-27
| | | | | | | | This buffer isn't needed after kmemleak was initialised so it can be freed together with the .init.data section. This patch also marks functions conditionally accessing the early log variables with __ref. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Dump object information on requestCatalin Marinas2009-08-27
| | | | | | | | By writing dump=<addr> to the kmemleak file, kmemleak will look up an object with that address and dump the information it has about it to syslog. This is useful in debugging memory leaks. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Allow rescheduling during an object scanningCatalin Marinas2009-08-27
| | | | | | | | | If the object size is bigger than a predefined value (4K in this case), release the object lock during scanning and call cond_resched(). Re-acquire the lock after rescheduling and test whether the object is still valid. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Protect the seq start/next/stop sequence by rcu_read_lock()Catalin Marinas2009-07-29
| | | | | | | | | | Objects passed to kmemleak_seq_next() have an incremented reference count (hence not freed) but they may point via object_list.next to other freed objects. To avoid this, the whole start/next/stop sequence must be protected by rcu_read_lock(). Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kmemleak: Allow partial freeing of memory blocksCatalin Marinas2009-07-08
| | | | | | | | | | | Functions like free_bootmem() are allowed to free only part of a memory block. This patch adds support for this via the kmemleak_free_part() callback which removes the original object and creates one or two additional objects as a result of the memory block split. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Ingo Molnar <mingo@elte.hu> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
* kmemleak: Scan objects allocated during a scanning episodeCatalin Marinas2009-07-08
| | | | | | | | | | | | | | | Many of the false positives in kmemleak happen on busy systems where objects are allocated during a kmemleak scanning episode. These objects aren't scanned by default until the next memory scan. When such object is added, for example, at the head of a list, it is possible that all the other objects in the list become unreferenced until the next scan. This patch adds checking for newly allocated objects at the end of the scan and repeats the scanning on these objects. If Linux allocates new objects at a higher rate than their scanning, it stops after a predefined number of passes. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Do not acquire scan_mutex in kmemleak_open()Catalin Marinas2009-07-08
| | | | | | | | | | | Initially, the scan_mutex was acquired in kmemleak_open() and released in kmemleak_release() (corresponding to /sys/kernel/debug/kmemleak operations). This was causing some lockdep reports when the file was closed from a different task than the one opening it. This patch moves the scan_mutex acquiring in kmemleak_write() or kmemleak_seq_start() with releasing in kmemleak_seq_stop(). Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Remove the reported leaks number limitationCatalin Marinas2009-07-08
| | | | | | | | Since the leaks are no longer printed to the syslog, there is no point in keeping this limitation. All the suspected leaks are shown on /sys/kernel/debug/kmemleak file. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Add more cond_resched() calls in the scanning threadCatalin Marinas2009-07-07
| | | | | | | | | | Following recent fix to no longer reschedule in the scan_block() function, the system may become unresponsive with !PREEMPT. This patch re-adds the cond_resched() call to scan_block() but conditioned by the allow_resched parameter. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Ingo Molnar <mingo@elte.hu>
* kmemleak: Renice the scanning thread to +10Catalin Marinas2009-07-07
| | | | | | | This is a long-running thread but not high-priority. So it makes sense to renice it to +10. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kmemleak: Fix scheduling-while-atomic bugIngo Molnar2009-07-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | One of the kmemleak changes caused the following scheduling-while-holding-the-tasklist-lock regression on x86: BUG: sleeping function called from invalid context at mm/kmemleak.c:795 in_atomic(): 1, irqs_disabled(): 0, pid: 1737, name: kmemleak 2 locks held by kmemleak/1737: #0: (scan_mutex){......}, at: [<c10c4376>] kmemleak_scan_thread+0x45/0x86 #1: (tasklist_lock){......}, at: [<c10c3bb4>] kmemleak_scan+0x1a9/0x39c Pid: 1737, comm: kmemleak Not tainted 2.6.31-rc1-tip #59266 Call Trace: [<c105ac0f>] ? __debug_show_held_locks+0x1e/0x20 [<c102e490>] __might_sleep+0x10a/0x111 [<c10c38d5>] scan_yield+0x17/0x3b [<c10c3970>] scan_block+0x39/0xd4 [<c10c3bc6>] kmemleak_scan+0x1bb/0x39c [<c10c4331>] ? kmemleak_scan_thread+0x0/0x86 [<c10c437b>] kmemleak_scan_thread+0x4a/0x86 [<c104d73e>] kthread+0x6e/0x73 [<c104d6d0>] ? kthread+0x0/0x73 [<c100959f>] kernel_thread_helper+0x7/0x10 kmemleak: 834 new suspected memory leaks (see /sys/kernel/debug/kmemleak) The bit causing it is highly dubious: static void scan_yield(void) { might_sleep(); if (time_is_before_eq_jiffies(next_scan_yield)) { schedule(); next_scan_yield = jiffies + jiffies_scan_yield; } } It called deep inside the codepath and in a conditional way, and that is what crapped up when one of the new scan_block() uses grew a tasklist_lock dependency. This minimal patch removes that yielding stuff and adds the proper cond_resched(). The background scanning thread could probably also be reniced to +10. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kmemleak: Do not warn if an unknown object is freedCatalin Marinas2009-06-29
| | | | | | | | | vmap'ed memory blocks are not tracked by kmemleak (yet) but they may be released with vfree() which is tracked. The corresponding kmemleak warning is only enabled in debug mode. Future patch will add support for ioremap and vmap. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-24 22:33:30 -0500