Subject: + mm-fix-page-leak-at-nfs_symlink.patch added to -mm tree
To: 
[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected]
From: [email protected]
Date: Fri, 07 Feb 2014 13:39:48 -0800


The patch titled
     Subject: mm: fix page leak at nfs_symlink()
has been added to the -mm tree.  Its filename is
     mm-fix-page-leak-at-nfs_symlink.patch

This patch should soon appear at
    
http://ozlabs.org/~akpm/mmots/broken-out/mm-fix-page-leak-at-nfs_symlink.patch
and later at
    
http://ozlabs.org/~akpm/mmotm/broken-out/mm-fix-page-leak-at-nfs_symlink.patch

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/SubmitChecklist when testing your code ***

The -mm tree is included into linux-next and is updated
there every 3-4 working days

------------------------------------------------------
From: Rafael Aquini <[email protected]>
Subject: mm: fix page leak at nfs_symlink()

Changes committed by a0b8cab3 ("mm: remove lru parameter from
__pagevec_lru_add and remove parts of pagevec API") have introduced a call
to add_to_page_cache_lru() which causes a leak in nfs_symlink() as now the
page gets an extra refcount that is not dropped.

Jan Stancek observed and reported the leak effect while running test8 from
Connectathon Testsuite.  After several iterations over the test case,
which creates several symlinks on a NFS mountpoint, the test system was
quickly getting into an out-of-memory scenario.

This patch fixes the page leak by dropping that extra refcount
add_to_page_cache_lru() is grabbing.

Signed-off-by: Jan Stancek <[email protected]>
Signed-off-by: Rafael Aquini <[email protected]>
Acked-by: Mel Gorman <[email protected]>
Acked-by: Rik van Riel <[email protected]>
Cc: Jeff Layton <[email protected]>
Cc: Trond Myklebust <[email protected]>
Cc: <[email protected]>    [3.11.x+]
Signed-off-by: Andrew Morton <[email protected]>
---

 fs/nfs/dir.c |    5 +++++
 1 file changed, 5 insertions(+)

diff -puN fs/nfs/dir.c~mm-fix-page-leak-at-nfs_symlink fs/nfs/dir.c
--- a/fs/nfs/dir.c~mm-fix-page-leak-at-nfs_symlink
+++ a/fs/nfs/dir.c
@@ -1846,6 +1846,11 @@ int nfs_symlink(struct inode *dir, struc
                                                        GFP_KERNEL)) {
                SetPageUptodate(page);
                unlock_page(page);
+               /*
+                * add_to_page_cache_lru() grabs an extra page refcount.
+                * Drop it here to avoid leaking this page later.
+                */
+               page_cache_release(page);
        } else
                __free_page(page);
 
_

Patches currently in -mm which might be from [email protected] are

mm-fix-page-leak-at-nfs_symlink.patch
mm-page_alloc-make-first_page-visible-before-pagetail.patch
linux-next.patch

--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to