diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index ea007615e8f9..e32ab948f589 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -83,11 +83,12 @@ static inline
 bool mm_match_cgroup(const struct mm_struct *mm, const struct mem_cgroup *memcg)
 {
 	struct mem_cgroup *task_memcg;
-	bool match;
+	bool match = false;
 
 	rcu_read_lock();
 	task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
-	match = __mem_cgroup_same_or_subtree(memcg, task_memcg);
+	if (task_memcg)
+		match = __mem_cgroup_same_or_subtree(memcg, task_memcg);
 	rcu_read_unlock();
 	return match;
 }
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 367cc57df362..e5dcebd71dfb 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1337,7 +1337,7 @@ bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg,
 {
 	if (root_memcg == memcg)
 		return true;
-	if (!root_memcg->use_hierarchy || !memcg)
+	if (!root_memcg->use_hierarchy)
 		return false;
 	return cgroup_is_descendant(memcg->css.cgroup, root_memcg->css.cgroup);
 }