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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-15 16:53:54 +08:00
linux-next/include
Oleg Nesterov d003f371b2 oom: don't assume that a coredumping thread will exit soon
oom_kill.c assumes that PF_EXITING task should exit and free the memory
soon.  This is wrong in many ways and one important case is the coredump.
A task can sleep in exit_mm() "forever" while the coredumping sub-thread
can need more memory.

Change the PF_EXITING checks to take SIGNAL_GROUP_COREDUMP into account,
we add the new trivial helper for that.

Note: this is only the first step, this patch doesn't try to solve other
problems.  The SIGNAL_GROUP_COREDUMP check is obviously racy, a task can
participate in coredump after it was already observed in PF_EXITING state,
so TIF_MEMDIE (which also blocks oom-killer) still can be wrongly set.
fatal_signal_pending() can be true because of SIGNAL_GROUP_COREDUMP so
out_of_memory() and mem_cgroup_out_of_memory() shouldn't blindly trust it.
 And even the name/usage of the new helper is confusing, an exiting thread
can only free its ->mm if it is the only/last task in thread group.

[akpm@linux-foundation.org: add comment]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 12:42:49 -08:00
..
acpi Merge branch 'pm-runtime' 2014-12-08 20:00:44 +01:00
asm-generic Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2014-12-11 17:30:55 -08:00
clocksource
crypto
drm
dt-bindings Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2014-12-11 17:56:37 -08:00
keys
kvm
linux oom: don't assume that a coredumping thread will exit soon 2014-12-13 12:42:49 -08:00
math-emu
media [media] media: v4l2-image-sizes.h: correct the SVGA height definition 2014-12-04 13:56:56 -02:00
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-12-11 14:27:06 -08:00
pcmcia
ras
rdma
rxrpc
scsi Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2014-12-12 10:08:06 -08:00
soc Merge branch 'at91/cleanup5' into next/drivers 2014-12-08 18:29:20 +01:00
sound sound updates for 3.19-rc1 2014-12-11 13:20:50 -08:00
target
trace Lots of bugs fixes, including Zheng and Jan's extent status shrinker 2014-12-12 09:28:03 -08:00
uapi Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-12-12 11:15:23 -08:00
video OMAPDSS: Remove all references to obsolete HDMI audio callbacks 2014-12-01 11:09:59 +02:00
xen xen/arm: introduce GNTTABOP_cache_flush 2014-12-04 12:41:54 +00:00
Kbuild