From 2a1dc509747fdcfdf3a2df818a14908aed86c3d4 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Mon, 1 Dec 2008 03:00:35 +0100 Subject: [PATCH] vmscan: protect zone rotation stats by lru lock The zone's rotation statistics must not be accessed without the corresponding LRU lock held. Fix an unprotected write in shrink_active_list(). Acked-by: Rik van Riel Reviewed-by: KOSAKI Motohiro Signed-off-by: Johannes Weiner Signed-off-by: Linus Torvalds --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 7ea1440b53d..62e7f62fb55 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1248,6 +1248,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, list_add(&page->lru, &l_inactive); } + spin_lock_irq(&zone->lru_lock); /* * Count referenced pages from currently used mappings as * rotated, even though they are moved to the inactive list. @@ -1263,7 +1264,6 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, pgmoved = 0; lru = LRU_BASE + file * LRU_FILE; - spin_lock_irq(&zone->lru_lock); while (!list_empty(&l_inactive)) { page = lru_to_page(&l_inactive); prefetchw_prev_lru_page(page, &l_inactive, flags); -- 2.20.1