diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 2011199476ea6b5a9c23309aad61f644e0e163d3..20e29e35884a8658c3f948a2a971a15c4312fb35 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -884,6 +884,16 @@ static void bdi_split_work_to_wbs(struct backing_dev_info *bdi,
 			continue;
 		}
 
+		/*
+		 * If wb_tryget fails, the wb has been shutdown, skip it.
+		 *
+		 * Pin @wb so that it stays on @bdi->wb_list.  This allows
+		 * continuing iteration from @wb after dropping and
+		 * regrabbing rcu read lock.
+		 */
+		if (!wb_tryget(wb))
+			continue;
+
 		/* alloc failed, execute synchronously using on-stack fallback */
 		work = &fallback_work;
 		*work = *base_work;
@@ -892,13 +902,6 @@ static void bdi_split_work_to_wbs(struct backing_dev_info *bdi,
 		work->done = &fallback_work_done;
 
 		wb_queue_work(wb, work);
-
-		/*
-		 * Pin @wb so that it stays on @bdi->wb_list.  This allows
-		 * continuing iteration from @wb after dropping and
-		 * regrabbing rcu read lock.
-		 */
-		wb_get(wb);
 		last_wb = wb;
 
 		rcu_read_unlock();
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 707bf409f5701bb3fc982e95f2d1e39987f3bc50..45ac57fd6e7a3c240a35942bfd5e4c1d6a9030de 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -378,6 +378,15 @@ static void wb_exit(struct bdi_writeback *wb)
 static DEFINE_SPINLOCK(cgwb_lock);
 static struct workqueue_struct *cgwb_release_wq;
 
+static void cgwb_free_rcu(struct rcu_head *rcu_head)
+{
+	struct bdi_writeback *wb = container_of(rcu_head,
+			struct bdi_writeback, rcu);
+
+	percpu_ref_exit(&wb->refcnt);
+	kfree(wb);
+}
+
 static void cgwb_release_workfn(struct work_struct *work)
 {
 	struct bdi_writeback *wb = container_of(work, struct bdi_writeback,
@@ -395,9 +404,8 @@ static void cgwb_release_workfn(struct work_struct *work)
 	blkcg_unpin_online(blkcg);
 
 	fprop_local_destroy_percpu(&wb->memcg_completions);
-	percpu_ref_exit(&wb->refcnt);
 	wb_exit(wb);
-	kfree_rcu(wb, rcu);
+	call_rcu(&wb->rcu, cgwb_free_rcu);
 }
 
 static void cgwb_release(struct percpu_ref *refcnt)