diff options
| author | KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> | 2007-07-26 10:41:08 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-26 11:35:17 -0700 |
| commit | 3dd9fe8c397df68086e6a1b2160573abbe944813 (patch) | |
| tree | 86dda41ade146e2a403151c7ba2f7e32a930bc63 /mm/migrate.c | |
| parent | dc386d4d1e98bb39fb967ee156cd456c802fc692 (diff) | |
| download | lwn-3dd9fe8c397df68086e6a1b2160573abbe944813.tar.gz lwn-3dd9fe8c397df68086e6a1b2160573abbe944813.zip | |
memory unplug: isolate_lru_page fix
release_pages() in mm/swap.c changes page_count() to be 0 without removing
PageLRU flag...
This means isolate_lru_page() can see a page, PageLRU() &&
page_count(page)==0.. This is BUG. (get_page() will be called against
count=0 page.)
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/migrate.c')
| -rw-r--r-- | mm/migrate.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index c8d87221f368..37c73b902008 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -49,9 +49,8 @@ int isolate_lru_page(struct page *page, struct list_head *pagelist) struct zone *zone = page_zone(page); spin_lock_irq(&zone->lru_lock); - if (PageLRU(page)) { + if (PageLRU(page) && get_page_unless_zero(page)) { ret = 0; - get_page(page); ClearPageLRU(page); if (PageActive(page)) del_page_from_active_list(zone, page); |