diff --git a/tools/virtio/vringh_test.c b/tools/virtio/vringh_test.c
index 13e0a76..51d922f 100644
--- a/tools/virtio/vringh_test.c
+++ b/tools/virtio/vringh_test.c
@@ -132,7 +132,7 @@
 	return 1;
 }
 
-static int parallel_test(unsigned long features,
+static int parallel_test(u64 features,
 			 bool (*getrange)(struct vringh *vrh,
 					  u64 addr, struct vringh_range *r),
 			 bool fast_vringh)