4.2-stable review patch. If anyone has any objections, please let me know.
------------------
From: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
commit 3aaa76e125c1dd58c9b599baa8c6021896874c12 upstream.
Since commit bcc54222309c ("mm: hugetlb: introduce page_huge_active")
each hugetlb page maintains its active flag to avoid a race condition
betwe= en multiple calls of isolate_huge_page(), but current kernel
doesn't set the f= lag on a hugepage allocated by migration because the
proper putback routine isn= 't called. This means that users could
still encounter the race referred to by bcc54222309c in this special
case, so this patch fixes it.
Fixes: bcc54222309c ("mm: hugetlb: introduce page_huge_active")
Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxx>
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
mm/migrate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1068,7 +1068,7 @@ out:
if (rc != MIGRATEPAGE_SUCCESS && put_new_page)
put_new_page(new_hpage, private);
else
- put_page(new_hpage);
+ putback_active_hugepage(new_hpage);
if (result) {
if (rc)
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html