diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 4b975111b536..1f467fb620fe 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -197,7 +197,7 @@ struct obj_cgroup {
 	struct mem_cgroup *memcg;
 	atomic_t nr_charged_bytes;
 	union {
-		struct list_head list;
+		struct list_head list; /* protected by objcg_lock */
 		struct rcu_head rcu;
 	};
 };
@@ -300,7 +300,8 @@ struct mem_cgroup {
 	int kmemcg_id;
 	enum memcg_kmem_state kmem_state;
 	struct obj_cgroup __rcu *objcg;
-	struct list_head objcg_list; /* list of inherited objcgs */
+	/* list of inherited objcgs, protected by objcg_lock */
+	struct list_head objcg_list;
 #endif
 
 	MEMCG_PADDING(_pad2_);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 4bb2a4c593f7..dbe07fef2682 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -250,7 +250,7 @@ struct cgroup_subsys_state *vmpressure_to_css(struct vmpressure *vmpr)
 }
 
 #ifdef CONFIG_MEMCG_KMEM
-extern spinlock_t css_set_lock;
+static DEFINE_SPINLOCK(objcg_lock);
 
 static void obj_cgroup_release(struct percpu_ref *ref)
 {
@@ -284,13 +284,13 @@ static void obj_cgroup_release(struct percpu_ref *ref)
 	WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1));
 	nr_pages = nr_bytes >> PAGE_SHIFT;
 
-	spin_lock_irqsave(&css_set_lock, flags);
+	spin_lock_irqsave(&objcg_lock, flags);
 	memcg = obj_cgroup_memcg(objcg);
 	if (nr_pages)
 		__memcg_kmem_uncharge(memcg, nr_pages);
 	list_del(&objcg->list);
 	mem_cgroup_put(memcg);
-	spin_unlock_irqrestore(&css_set_lock, flags);
+	spin_unlock_irqrestore(&objcg_lock, flags);
 
 	percpu_ref_exit(ref);
 	kfree_rcu(objcg, rcu);
@@ -322,7 +322,7 @@ static void memcg_reparent_objcgs(struct mem_cgroup *memcg,
 
 	objcg = rcu_replace_pointer(memcg->objcg, NULL, true);
 
-	spin_lock_irq(&css_set_lock);
+	spin_lock_irq(&objcg_lock);
 
 	/* Move active objcg to the parent's list */
 	xchg(&objcg->memcg, parent);
@@ -337,7 +337,7 @@ static void memcg_reparent_objcgs(struct mem_cgroup *memcg,
 	}
 	list_splice(&memcg->objcg_list, &parent->objcg_list);
 
-	spin_unlock_irq(&css_set_lock);
+	spin_unlock_irq(&objcg_lock);
 
 	percpu_ref_kill(&objcg->refcnt);
 }