--- sys/dev/ctau/if_ct.c	2008-11-22 14:40:14.000000000 +0800
+++ /var/current/mysrc/sys/dev/ctau/if_ct.c	2008-11-24 11:31:36.000000000 +0800
@@ -572,7 +572,8 @@
 
 	KASSERT ((bd != NULL), ("ct%d: NULL device softc\n", unit));
 	
-	bus_get_resource (dev, SYS_RES_IOPORT, 0, &iobase, &rescount);
+	if (bus_get_resource (dev, SYS_RES_IOPORT, 0, &iobase, &rescount) != 0)
+		return (ENXIO);
 	bd->base_rid = 0;
 	bd->base_res = bus_alloc_resource (dev, SYS_RES_IOPORT, &bd->base_rid,
 		iobase, iobase + NPORT, NPORT, RF_ACTIVE);