1 files changed, 15 insertions, 4 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 2a1f7847b6ad..7bc30707d0c6 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1238,10 +1238,21 @@ int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg)
         struct task_struct *p;
 
         p = find_lock_task_mm(task);
-        if (!p)
-                return 0;
-        curr = try_get_mem_cgroup_from_mm(p->mm);
-        task_unlock(p);
+        if (p) {
+                curr = try_get_mem_cgroup_from_mm(p->mm);
+                task_unlock(p);
+        } else {
+                /*
+                 * All threads may have already detached their mm's, but the oom
+                 * killer still needs to detect if they have already been oom
+                 * killed to prevent needlessly killing additional tasks.
+                 */
+                task_lock(task);
+                curr = mem_cgroup_from_task(task);
+                if (curr)
+                        css_get(&curr->css);
+                task_unlock(task);
+        }
         if (!curr)
                 return 0;
         /*