diff --git a/drivers/xen/cpu_hotplug.c b/drivers/xen/cpu_hotplug.c
index bdfd584..6625ffe 100644
--- a/drivers/xen/cpu_hotplug.c
+++ b/drivers/xen/cpu_hotplug.c
@@ -1,5 +1,6 @@
 #include <linux/notifier.h>
 
+#include <xen/xen.h>
 #include <xen/xenbus.h>
 
 #include <asm/xen/hypervisor.h>