diff --git a/sys/dev/powermng/clockmod/clockmod.c b/sys/dev/powermng/clockmod/clockmod.c
--- a/sys/dev/powermng/clockmod/clockmod.c
+++ b/sys/dev/powermng/clockmod/clockmod.c
@@ -393,7 +393,7 @@
 
 	lwkt_serialize_enter(&clockmod_dom_slize);
 
-	if ((dom->dom_flags & CLOCKMOD_DOM_FLAG_ACTIVE) == 0) {
+	if (dom == NULL || (dom->dom_flags & CLOCKMOD_DOM_FLAG_ACTIVE) == 0) {
 		error = SYSCTL_OUT(req, " ", 1);
 		goto done;
 	}