diff --git a/tests/virttest b/tests/virttest
index bb9661900f278dd487f4a82d040849ea72b1a614..c12681a27abe705ab6634db0b88a0676014e46ad 100755
--- a/tests/virttest
+++ b/tests/virttest
@@ -4,6 +4,7 @@
 # - vt_reference
 # - vt_type
 # - vt_guest_os
+# - sub_module
 ## - vt_machine_type
 ## - vt_no_filter
 ## - vt_only_filter