diff --git a/drivers/md/md.c b/drivers/md/md.c
index 939739f0f881..5fcce7371ee9 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -4014,8 +4014,10 @@ new_dev_store(struct mddev *mddev, const char *buf, size_t len)
 	else
 		rdev = md_import_device(dev, -1, -1);
 
-	if (IS_ERR(rdev))
+	if (IS_ERR(rdev)) {
+		mddev_unlock(mddev);
 		return PTR_ERR(rdev);
+	}
 	err = bind_rdev_to_array(rdev, mddev);
  out:
 	if (err)