diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 6674c12..cc110cc 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -289,7 +289,13 @@ struct mem_cgroup {
 
 #ifdef CONFIG_MEMCG_KMEM
 	int kmemcg_id;
-	struct obj_cgroup __rcu *objcg;
+	/*
+	 * memcg->objcg is wiped out as a part of the objcg repaprenting
+	 * process. memcg->orig_objcg preserves a pointer (and a reference)
+	 * to the original objcg until the end of live of memcg.
+	 */
+	struct obj_cgroup __rcu	*objcg;
+	struct obj_cgroup	*orig_objcg;
 	/* list of inherited objcgs, protected by objcg_lock */
 	struct list_head objcg_list;
 #endif
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 96f4c31..ff036d5 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3899,6 +3899,8 @@ static int memcg_online_kmem(struct mem_cgroup *memcg)
 
 	objcg->memcg = memcg;
 	rcu_assign_pointer(memcg->objcg, objcg);
+	obj_cgroup_get(objcg);
+	memcg->orig_objcg = objcg;
 
 	static_branch_enable(&memcg_kmem_online_key);
 
@@ -5406,6 +5408,9 @@ static void __mem_cgroup_free(struct mem_cgroup *memcg)
 {
 	int node;
 
+	if (memcg->orig_objcg)
+		obj_cgroup_put(memcg->orig_objcg);
+
 	for_each_node(node)
 		free_mem_cgroup_per_node_info(memcg, node);
 	kfree(memcg->vmstats);