diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index 9d92153..8bbc371 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _BLK_CGROUP_H
 #define _BLK_CGROUP_H
 /*