--- sys/dev/wbwd/wbwd.c	2015-06-02 13:37:27.000000000 +0900
+++ sys/dev/wbwd/wbwd.c	2015-09-17 10:20:28.602408000 +0900
@@ -689,7 +689,7 @@ 
 	struct sysctl_ctx_list *sctx;
 	struct sysctl_oid *soid;
 	unsigned long timeout;
-	int error;
+	int error, wden;
 
 	error = wb_probe_enable(dev, 0);
 	if (error > 0)
@@ -716,7 +716,8 @@ 
 	sc->reg_2 = read_efdr_1(sc, 0);
 
 	/* Print current state if bootverbose or watchdog already enabled. */
-	if (bootverbose || (sc->reg_timeout > 0x00))
+	wden = (sc->reg_timeout > 0x00) ? 1 : 0;
+	if (bootverbose || wden)
 		wb_print_state(sc, "Before watchdog attach");
 
 	/*
@@ -760,7 +761,14 @@ 
 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, wb_watchdog_fn, sc,
 	    0);
 
-	if (bootverbose)
+	/* Disable until watchdogd(8) re-enables, if it's already enabled. */
+	if (wden) {
+		error = wb_set_watchdog(sc, 0);
+		if (error)
+			return (error);
+	}
+
+	if (bootverbose || wden)
 		wb_print_state(sc, "After watchdog attach");
 
 	return (0);