diff --git a/arch/arm64/kernel/include/arch-lock.h b/arch/arm64/kernel/include/arch-lock.h
index 6fd6aa2d..10930016 100644
--- a/arch/arm64/kernel/include/arch-lock.h
+++ b/arch/arm64/kernel/include/arch-lock.h
@@ -6,6 +6,7 @@
 
 #include <ihk/cpu.h>
 #include <ihk/atomic.h>
+#include "affinity.h"
 
 //#define DEBUG_SPINLOCK
 //#define DEBUG_MCS_RWLOCK