3.10-stable review patch. If anyone has any objections, please let me know.
------------------ From: Naoya Horiguchi <[email protected]> commit 8d547ff4ac5927245e0833ac18528f939da0ee0e upstream. mce-test detected a test failure when injecting error to a thp tail page. This is because we take page refcount of the tail page in madvise_hwpoison() while the fix in commit a3e0f9e47d5e ("mm/memory-failure.c: transfer page count from head page to tail page after split thp") assumes that we always take refcount on the head page. When a real memory error happens we take refcount on the head page where memory_failure() is called without MF_COUNT_INCREASED set, so it seems to me that testing memory error on thp tail page using madvise makes little sense. This patch cancels moving refcount in !MF_COUNT_INCREASED for valid testing. [[email protected]: s/&&/&/] Signed-off-by: Naoya Horiguchi <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Wanpeng Li <[email protected]> Cc: Chen Gong <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- mm/memory-failure.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -943,8 +943,10 @@ static int hwpoison_user_mappings(struct * to it. Similarly, page lock is shifted. */ if (hpage != p) { - put_page(hpage); - get_page(p); + if (!(flags & MF_COUNT_INCREASED)) { + put_page(hpage); + get_page(p); + } lock_page(p); unlock_page(hpage); *hpagep = p; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
