diff --git a/lib/dump_stack.c b/lib/dump_stack.c
index 625375e..c5edbed 100644
--- a/lib/dump_stack.c
+++ b/lib/dump_stack.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Provide a default dump_stack() function for architectures
  * which don't implement their own.