diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 5cf0a9d29bf04c9846f02c11cb8ca3baee1839e0..8b7d55bf5aa288a0710428ea43ebd066178a00ec 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -104,6 +104,7 @@ enum msg_type {
 	REMOVE,
 	RE_ADD,
 	BITMAP_NEEDS_SYNC,
+	CHANGE_CAPACITY,
 };
 
 struct cluster_msg {
@@ -579,6 +580,10 @@ static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
 	case METADATA_UPDATED:
 		process_metadata_update(mddev, msg);
 		break;
+	case CHANGE_CAPACITY:
+		set_capacity(mddev->gendisk, mddev->array_sectors);
+		revalidate_disk(mddev->gendisk);
+		break;
 	case RESYNCING:
 		process_suspend_info(mddev, le32_to_cpu(msg->slot),
 				     le64_to_cpu(msg->low),