Subject: + mm-fix-page-leak-at-nfs_symlink.patch added to -mm tree To: aquini@xxxxxxxxxx,jlayton@xxxxxxxxxx,jstancek@xxxxxxxxxx,mgorman@xxxxxxx,riel@xxxxxxxxxx,stable@xxxxxxxxxxxxxxx,trond.myklebust@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx 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 <aquini@xxxxxxxxxx> 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 <jstancek@xxxxxxxxxx> Signed-off-by: Rafael Aquini <aquini@xxxxxxxxxx> Acked-by: Mel Gorman <mgorman@xxxxxxx> Acked-by: Rik van Riel <riel@xxxxxxxxxx> Cc: Jeff Layton <jlayton@xxxxxxxxxx> Cc: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> [3.11.x+] Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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 aquini@xxxxxxxxxx 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 mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html