diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3ca3cfb03a7e..ec802913f977 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5028,8 +5028,10 @@ static int md_notify_reboot(struct notifier_block *this,
 		printk(KERN_INFO "md: stopping all md devices.\n");
 
 		ITERATE_MDDEV(mddev,tmp)
-			if (mddev_trylock(mddev))
+			if (mddev_trylock(mddev)) {
 				do_md_stop (mddev, 1);
+				mddev_unlock(mddev);
+			}
 		/*
 		 * certain more exotic SCSI devices are known to be
 		 * volatile wrt too early system reboots. While the