From db0480b3a61bd6ad86ead3b8bbad094ab0996932 Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Wed, 16 Dec 2009 12:19:58 +0100 Subject: [PATCH] HWPOISON: comment the possible set_page_dirty() race Signed-off-by: Wu Fengguang Signed-off-by: Andi Kleen --- mm/memory-failure.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index b62287d..dc47415 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -687,6 +687,8 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn, /* * Propagate the dirty bit from PTEs to struct page first, because we * need this to decide if we should kill or just drop the page. + * XXX: the dirty test could be racy: set_page_dirty() may not always + * be called inside page lock (it's recommended but not enforced). */ mapping = page_mapping(p); if (!PageDirty(p) && mapping && mapping_cap_writeback_dirty(mapping)) { -- 1.8.2.3