diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index a4a838306b2c..07c6d42ab5ff 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -9,6 +9,7 @@
 #include <asm/desc.h>
 #include <asm/hpet.h>
 #include <asm/pgtable.h>
+#include <asm/proto.h>
 #include <asm/reboot_fixups.h>
 #include <asm/reboot.h>