tree 695f97a4d028a3463c8e7edaa4c6d410a941d0bb
parent 932e9f352b5d685725076f21b237f7c7d804b29c
author Hugh Dickins <hughd@google.com> 1334817286 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1334817657 -0700

memcg: fix Bad page state after replace_page_cache

My 9ce70c0240d0 "memcg: fix deadlock by inverting lrucare nesting" put a
nasty little bug into v3.3's version of mem_cgroup_replace_page_cache(),
sometimes used for FUSE.  Replacing __mem_cgroup_commit_charge_lrucare()
by __mem_cgroup_commit_charge(), I used the "pc" pointer set up earlier:
but it's for oldpage, and needs now to be for newpage.  Once oldpage was
freed, its PageCgroupUsed bit (cleared above but set again here) caused
"Bad page state" messages - and perhaps worse, being missed from newpage.
(I didn't find this by using FUSE, but in reusing the function for tmpfs.)

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org [v3.3 only]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>