From bd486285f24ac2fd1ff64688fb0729712c5712c4 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Tue, 24 May 2011 17:12:20 -0700 Subject: [PATCH] mem-hwpoison: fix page refcount around isolate_lru_page() Drop first page reference only after calling isolate_lru_page() to keep page stable reference while isolating. Signed-off-by: Konstantin Khlebnikov Cc: Andi Kleen Cc: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro Cc: Mel Gorman Cc: Lee Schermerhorn Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory-failure.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 12178ec32ab5..369b80e81416 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1440,16 +1440,12 @@ int soft_offline_page(struct page *page, int flags) */ ret = invalidate_inode_page(page); unlock_page(page); - /* - * Drop count because page migration doesn't like raised - * counts. The page could get re-allocated, but if it becomes - * LRU the isolation will just fail. * RED-PEN would be better to keep it isolated here, but we * would need to fix isolation locking first. */ - put_page(page); if (ret == 1) { + put_page(page); ret = 0; pr_info("soft_offline: %#lx: invalidated\n", pfn); goto done; @@ -1461,6 +1457,11 @@ int soft_offline_page(struct page *page, int flags) * handles a large number of cases for us. */ ret = isolate_lru_page(page); + /* + * Drop page reference which is came from get_any_page() + * successful isolate_lru_page() already took another one. + */ + put_page(page); if (!ret) { LIST_HEAD(pagelist);