TTU_SYNC prevents an unlikely race, when try_to_unmap() returns shortly before the page is accounted as unmapped. It is unlikely to coincide with hwpoisoning, but now that we have the flag, hwpoison_user_mappings() would do well to use it. Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> --- Patch added since the v1 series was posted. mm/memory-failure.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index b6806e446567..e16edefca523 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1060,7 +1060,7 @@ static int get_hwpoison_page(struct page *p, unsigned long flags, static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, int flags, struct page **hpagep) { - enum ttu_flags ttu = TTU_IGNORE_MLOCK; + enum ttu_flags ttu = TTU_IGNORE_MLOCK | TTU_SYNC; struct address_space *mapping; LIST_HEAD(tokill); bool unmap_success; -- 2.26.2