diff options
-rw-r--r-- | mm/memory.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/mm/memory.c b/mm/memory.c index 71b161b73bb5..0e18b4d649ec 100644 --- a/mm/memory.c +++ b/mm/memory.c | |||
@@ -2680,10 +2680,12 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, | |||
2680 | delayacct_clear_flag(DELAYACCT_PF_SWAPIN); | 2680 | delayacct_clear_flag(DELAYACCT_PF_SWAPIN); |
2681 | 2681 | ||
2682 | /* | 2682 | /* |
2683 | * Make sure try_to_free_swap didn't release the swapcache | 2683 | * Make sure try_to_free_swap or reuse_swap_page or swapoff did not |
2684 | * from under us. The page pin isn't enough to prevent that. | 2684 | * release the swapcache from under us. The page pin, and pte_same |
2685 | * test below, are not enough to exclude that. Even if it is still | ||
2686 | * swapcache, we need to check that the page's swap has not changed. | ||
2685 | */ | 2687 | */ |
2686 | if (unlikely(!PageSwapCache(page))) | 2688 | if (unlikely(!PageSwapCache(page) || page_private(page) != entry.val)) |
2687 | goto out_page; | 2689 | goto out_page; |
2688 | 2690 | ||
2689 | if (ksm_might_need_to_copy(page, vma, address)) { | 2691 | if (ksm_might_need_to_copy(page, vma, address)) { |