diff options
| author | Mel Gorman <mgorman@suse.de> | 2012-12-05 14:01:41 -0800 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2013-01-03 03:32:54 +0000 |
| commit | c6dc8bee909fd3b11d9f591165bd614e3c3ab99d (patch) | |
| tree | 9ee099366de6e8b762df73e7eca8a4b6022c9ce0 /include | |
| parent | d8c2239fcc2c65572d199b010f7903d05a839502 (diff) | |
tmpfs: fix shared mempolicy leak
commit 18a2f371f5edf41810f6469cb9be39931ef9deb9 upstream.
This fixes a regression in 3.7-rc, which has since gone into stable.
Commit 00442ad04a5e ("mempolicy: fix a memory corruption by refcount
imbalance in alloc_pages_vma()") changed get_vma_policy() to raise the
refcount on a shmem shared mempolicy; whereas shmem_alloc_page() went
on expecting alloc_page_vma() to drop the refcount it had acquired.
This deserves a rework: but for now fix the leak in shmem_alloc_page().
Hugh: shmem_swapin() did not need a fix, but surely it's clearer to use
the same refcounting there as in shmem_alloc_page(), delete its onstack
mempolicy, and the strange mpol_cond_copy() and __mpol_cond_copy() -
those were invented to let swapin_readahead() make an unknown number of
calls to alloc_pages_vma() with one mempolicy; but since 00442ad04a5e,
alloc_pages_vma() has kept refcount in balance, so now no problem.
Reported-and-tested-by: Tommi Rantala <tt.rantala@gmail.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/mempolicy.h | 16 |
1 files changed, 0 insertions, 16 deletions
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h index 3e8f2f705b37..f85c5ab2cc54 100644 --- a/include/linux/mempolicy.h +++ b/include/linux/mempolicy.h @@ -137,16 +137,6 @@ static inline void mpol_cond_put(struct mempolicy *pol) __mpol_put(pol); } -extern struct mempolicy *__mpol_cond_copy(struct mempolicy *tompol, - struct mempolicy *frompol); -static inline struct mempolicy *mpol_cond_copy(struct mempolicy *tompol, - struct mempolicy *frompol) -{ - if (!frompol) - return frompol; - return __mpol_cond_copy(tompol, frompol); -} - extern struct mempolicy *__mpol_dup(struct mempolicy *pol); static inline struct mempolicy *mpol_dup(struct mempolicy *pol) { @@ -270,12 +260,6 @@ static inline void mpol_cond_put(struct mempolicy *pol) { } -static inline struct mempolicy *mpol_cond_copy(struct mempolicy *to, - struct mempolicy *from) -{ - return from; -} - static inline void mpol_get(struct mempolicy *pol) { } |