1 files changed, 4 insertions, 3 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c31a310aa146..e0c2066495e3 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1737,11 +1737,12 @@ int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
                 goto charge_cur_mm;
         /*
          * A racing thread's fault, or swapoff, may have already updated
-         * the pte, and even removed page from swap cache: return success
-         * to go on to do_swap_page()'s pte_same() test, which should fail.
+         * the pte, and even removed page from swap cache: in those cases
+         * do_swap_page()'s pte_same() test will fail; but there's also a
+         * KSM case which does need to charge the page.
          */
         if (!PageSwapCache(page))
-                return 0;
+                goto charge_cur_mm;
         mem = try_get_mem_cgroup_from_swapcache(page);
         if (!mem)
                 goto charge_cur_mm;