diff options
author | David Rientjes <rientjes@google.com> | 2007-05-06 14:50:00 -0700 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-05-07 12:12:55 -0700 |
commit | 2b45ab3398a0ba119b1f672c7c56fd5a431b7f0a (patch) | |
tree | 302238b786d2137111244702345acf6d4a17d4b7 /arch/alpha/kernel | |
parent | 2b744c01a54fe0c9974ff1b29522f25f07084053 (diff) |
oom: fix constraint deadlock
Fixes a deadlock in the OOM killer for allocations that are not
__GFP_HARDWALL.
Before the OOM killer checks for the allocation constraint, it takes
callback_mutex.
constrained_alloc() iterates through each zone in the allocation zonelist
and calls cpuset_zone_allowed_softwall() to determine whether an allocation
for gfp_mask is possible. If a zone's node is not in the OOM-triggering
task's mems_allowed, it is not exiting, and we did not fail on a
__GFP_HARDWALL allocation, cpuset_zone_allowed_softwall() attempts to take
callback_mutex to check the nearest exclusive ancestor of current's cpuset.
This results in deadlock.
We now take callback_mutex after iterating through the zonelist since we
don't need it yet.
Cc: Andi Kleen <ak@suse.de>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Martin J. Bligh <mbligh@mbligh.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/alpha/kernel')
0 files changed, 0 insertions, 0 deletions