diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c
index 41a18ece029a33883b2ef719b1694f6768c45222..9eae1fceec1e562876cb038f32483bf19a05ec90 100644
--- a/drivers/xen/pvcalls-back.c
+++ b/drivers/xen/pvcalls-back.c
@@ -24,7 +24,7 @@
 #define PVCALLS_VERSIONS "1"
 #define MAX_RING_ORDER XENBUS_MAX_RING_GRANT_ORDER
 
-struct pvcalls_back_global {
+static struct pvcalls_back_global {
 	struct list_head frontends;
 	struct semaphore frontends_lock;
 } pvcalls_back_global;