tree b8e0a03d787c2219b1d1fd833193de7abc59442e
parent 12aee278b50c4a94a93fa0b4d201ae35d792c696
author Johannes Weiner <hannes@cmpxchg.org> 1383262453 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1383263893 -0700

mm: memcg: use proper memcg in limit bypass

Commit 84235de394d9 ("fs: buffer: move allocation failure loop into the
allocator") allowed __GFP_NOFAIL allocations to bypass the limit if they
fail to reclaim enough memory for the charge.  But because the main test
case was on a 3.2-based system, the patch missed the fact that on newer
kernels the charge function needs to return root_mem_cgroup when
bypassing the limit, and not NULL.  This will corrupt whatever memory is
at NULL + percpu pointer offset.  Fix this quickly before problems are
reported.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>