Oleg Nesterov dd8e8f405c oom: introduce find_lock_task_mm() to fix !mm false positives ... Almost all ->mm == NULL checks in oom_kill.c are wrong. The current code assumes that the task without ->mm has already released its memory and ignores the process. However this is not necessarily true when this process is multithreaded, other live sub-threads can use this ->mm. - Remove the "if (!p->mm)" check in select_bad_process(), it is just wrong. - Add the new helper, find_lock_task_mm(), which finds the live thread which uses the memory and takes task_lock() to pin ->mm - change oom_badness() to use this helper instead of just checking ->mm != NULL. - As David pointed out, select_bad_process() must never choose the task without ->mm, but no matter what oom_badness() returns the task can be chosen if nothing else has been found yet. Change oom_badness() to return int, change it to return -1 if find_lock_task_mm() fails, and change select_bad_process() to check points >= 0. Note! This patch is not enough, we need more changes. - oom_badness() was fixed, but oom_kill_task() still ignores the task without ->mm - oom_forkbomb_penalty() should use find_lock_task_mm() too, and it also needs other changes to actually find the first first-descendant children This will be addressed later. [kosaki.motohiro@jp.fujitsu.com: use in badness(), __oom_kill_task()] Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: 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>		2010-08-09 20:44:55 -07:00
..
backing-dev.c	Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-08-06 09:23:07 -07:00
bootmem.c	x86,nobootmem: make alloc_bootmem_node fall back to other node when 32bit numa is used	2010-07-20 16:25:40 -07:00
bounce.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
compaction.c	mm: compaction: add a tunable that decides when memory should be compacted and when it should be reclaimed	2010-05-25 08:06:59 -07:00
debug-pagealloc.c	generic debug pagealloc	2009-04-01 08:59:13 -07:00
dmapool.c	dmapools: protect page_list walk in show_pools()	2009-06-30 18:56:00 -07:00
fadvise.c	readahead: introduce FMODE_RANDOM for POSIX_FADV_RANDOM	2010-03-06 11:26:25 -08:00
failslab.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
filemap_xip.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
filemap.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse	2010-05-30 09:16:14 -07:00
fremap.c	mm: clean up mm_counter	2010-03-06 11:26:23 -08:00
highmem.c	mm,kdb,kgdb: Add a debug reference for the kdb kmap usage	2010-08-05 09:22:24 -05:00
hugetlb.c	hugetlb: call mmu notifiers on hugepage cow	2010-08-09 20:44:54 -07:00
hwpoison-inject.c	HWPOISON: Don't do early filtering if filter is disabled	2009-12-16 12:20:01 +01:00
init-mm.c	mm: provide init_mm mm_context initializer	2010-08-09 20:44:54 -07:00
internal.h	HWPOISON: add an interface to switch off/on all the page filters	2009-12-16 12:19:59 +01:00
Kconfig	lmb: rename to memblock	2010-07-14 17:14:00 +10:00
Kconfig.debug	trivial: improve help text for mm debug config options	2009-09-21 15:14:57 +02:00
kmemcheck.c	kmemcheck: Fix build errors due to missing slab.h	2010-03-30 22:02:32 +09:00
kmemleak-test.c	percpu: clean up percpu variable definitions	2009-06-24 15:13:48 +09:00
kmemleak.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
ksm.c	mm: extend KSM refcounts to the anon_vma root	2010-08-09 20:44:55 -07:00
maccess.c	maccess,probe_kernel: Allow arch specific override probe_kernel_(read|write)	2010-01-07 11:58:36 -06:00
madvise.c	HWPOISON: Add a madvise() injector for soft page offlining	2009-12-16 12:20:00 +01:00
Makefile	lmb: rename to memblock	2010-07-14 17:14:00 +10:00
memblock.c	lmb: rename to memblock	2010-07-14 17:14:00 +10:00
memcontrol.c	memcg: fix wake up in oom wait queue	2010-06-29 15:29:30 -07:00
memory_hotplug.c	mem-hotplug: fix potential race while building zonelist for new populated zone	2010-05-25 08:07:02 -07:00
memory-failure.c	KVM: Fix a race condition for usage of is_hwpoison_address()	2010-08-01 10:47:11 +03:00
memory.c	mm: fix ia64 crash when gcore reads gate area	2010-07-30 18:56:09 -07:00
mempolicy.c	mempolicy: fix dangling reference to tmpfs superblock mpol	2010-06-29 15:29:31 -07:00
mempool.c	mm: remove broken 'kzalloc' mempool	2009-09-22 07:17:35 -07:00
migrate.c	mm: extend KSM refcounts to the anon_vma root	2010-08-09 20:44:55 -07:00
mincore.c	mincore: do nested page table walks	2010-05-25 08:06:58 -07:00
mlock.c	x86, perf, bts, mm: Delete the never used BTS-ptrace code	2010-03-26 11:33:55 +01:00
mm_init.c	mm: mminit_loglevel cannot be __meminitdata anymore	2008-08-20 15:40:30 -07:00
mmap.c	mm: always lock the root (oldest) anon_vma	2010-08-09 20:44:55 -07:00
mmu_context.c	exit: fix oops in sync_mm_rss	2010-03-24 16:31:21 -07:00
mmu_notifier.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
mmzone.c	[ARM] Double check memmap is actually valid with a memmap has unexpected holes V2	2009-05-18 11:22:24 +01:00
mprotect.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
mremap.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
msync.c	sanitize vfs_fsync calling conventions	2010-05-21 18:31:21 -04:00
nommu.c	nommu: allow private mappings of read-only devices	2010-05-26 08:19:23 -07:00
oom_kill.c	oom: introduce find_lock_task_mm() to fix !mm false positives	2010-08-09 20:44:55 -07:00
page_alloc.c	x86,nobootmem: make alloc_bootmem_node fall back to other node when 32bit numa is used	2010-07-20 16:25:40 -07:00
page_cgroup.c	kmemleak: Annotate false positive in init_section_page_cgroup()	2010-07-19 11:54:14 +01:00
page_io.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
page_isolation.c	memory hotplug: fix page_zone() calculation in test_pages_isolated()	2008-11-06 15:41:19 -08:00
page-writeback.c	writeback: remove writeback_inodes_wbc	2010-07-06 08:54:03 +02:00
pagewalk.c	pagemap: fix pfn calculation for hugepage	2010-04-07 08:38:04 -07:00
percpu_up.c	percpu: don't implicitly include slab.h from percpu.h	2010-03-30 22:02:32 +09:00
percpu-km.c	percpu: implement kernel memory based chunk allocation	2010-05-01 08:30:50 +02:00
percpu-vm.c	percpu: move vmalloc based chunk management into percpu-vm.c	2010-05-01 08:30:50 +02:00
percpu.c	percpu: allow limited allocation before slab is online	2010-06-27 18:50:00 +02:00
prio_tree.c
quicklist.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
readahead.c	readahead.c: fix comment	2010-05-25 08:07:00 -07:00
rmap.c	mm: extend KSM refcounts to the anon_vma root	2010-08-09 20:44:55 -07:00
shmem.c	fix truncate inode time modification breakage	2010-06-04 17:16:30 -04:00
slab.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6	2010-08-06 11:44:08 -07:00
slob.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6	2010-08-06 11:44:08 -07:00
slub.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6	2010-08-06 11:44:08 -07:00
sparse-vmemmap.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
sparse.c	sparsemem: on no vmemmap path put mem_map on node high too	2010-05-25 08:06:56 -07:00
swap_state.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
swap.c	mm: export lru_cache_add_*() to modules	2010-05-25 15:06:06 +02:00
swapfile.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6	2010-05-21 15:26:46 -07:00
thrash.c	mm: pass mm to grab_swap_token	2009-06-23 12:50:05 -07:00
truncate.c	fs: introduce new truncate sequence	2010-05-27 22:15:33 -04:00
util.c	mm: use memdup_user	2010-08-09 20:44:54 -07:00
vmalloc.c	mm: use ERR_CAST	2010-08-09 20:44:54 -07:00
vmscan.c	mm/vmscan.c: fix mapping use after free	2010-07-20 16:25:40 -07:00
vmstat.c	mm: compaction: direct compact when a high-order allocation fails	2010-05-25 08:06:59 -07:00