diff options
-rw-r--r-- | mm/vmscan.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index fbcac3bdcf1..777af57fd8c 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -544,6 +544,16 @@ redo: */ lru = LRU_UNEVICTABLE; add_page_to_unevictable_list(page); + /* + * When racing with an mlock clearing (page is + * unlocked), make sure that if the other thread does + * not observe our setting of PG_lru and fails + * isolation, we see PG_mlocked cleared below and move + * the page back to the evictable list. + * + * The other side is TestClearPageMlocked(). + */ + smp_mb(); } /* |