diff --git a/src/cpu/x86/Kconfig b/src/cpu/x86/Kconfig
index 6c784b4..ec1fa13 100644
--- a/src/cpu/x86/Kconfig
+++ b/src/cpu/x86/Kconfig
@@ -1,3 +1,5 @@
+## SPDX-License-Identifier: GPL-2.0-only
+
 if ARCH_X86
 
 config PARALLEL_MP