| From | Greg Kroah-Hartman <> | Subject | [PATCH 3.14 103/122] mm: madvise: fix MADV_WILLNEED on shmem swapouts | Date | Wed, 19 Nov 2014 12:52:33 -0800 |
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3.14-stable review patch. If anyone has any objections, please let me know.
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From: Johannes Weiner <hannes@cmpxchg.org>
commit 55231e5c898c5c03c14194001e349f40f59bd300 upstream.
MADV_WILLNEED currently does not read swapped out shmem pages back in.
Commit 0cd6144aadd2 ("mm + fs: prepare for non-page entries in page cache radix trees") made find_get_page() filter exceptional radix tree entries but failed to convert all find_get_page() callers that WANT exceptional entries over to find_get_entry(). One of them is shmem swap readahead in madvise, which now skips over any swap-out records.
Convert it to find_get_entry().
Fixes: 0cd6144aadd2 ("mm + fs: prepare for non-page entries in page cache radix trees") Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- mm/madvise.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/madvise.c +++ b/mm/madvise.c @@ -195,7 +195,7 @@ static void force_shm_swapin_readahead(s for (; start < end; start += PAGE_SIZE) { index = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; - page = find_get_page(mapping, index); + page = find_get_entry(mapping, index); if (!radix_tree_exceptional_entry(page)) { if (page) page_cache_release(page);
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