--- a/sys/bus/u4b/wlan/if_mtw.c
+++ b/sys/bus/u4b/wlan/if_mtw.c
@@ -691,6 +691,7 @@
 
 detach:
 	MTW_UNLOCK(sc);
+detach_nolock:
 	mtw_detach(self);
 	return (ENXIO);
 }