diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 8beb2bc60f7de1d07174d50f9cf12fbd98a65e23..b4e73011a80e109286022b1185eb50d957bc8401 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -261,7 +261,7 @@ static void init_evtchn_cpu_bindings(void)
 	}
 #endif
 
-	memset(cpu_evtchn_mask(0), ~0, sizeof(cpu_evtchn_mask(0)));
+	memset(cpu_evtchn_mask(0), ~0, sizeof(struct cpu_evtchn_s));
 }
 
 static inline void clear_evtchn(int port)