diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c
index 68119f6..f3594ec 100644
--- a/drivers/xen/evtchn.c
+++ b/drivers/xen/evtchn.c
@@ -99,7 +99,7 @@
 		port_user[port] &= ~1;
 }
 
-irqreturn_t evtchn_interrupt(int irq, void *data)
+static irqreturn_t evtchn_interrupt(int irq, void *data)
 {
 	unsigned int port = (unsigned long)data;
 	struct per_user_data *u;