From d5ca7f4f2b3f950eceb91ff6d4e4a7ec2505dae1 Mon Sep 17 00:00:00 2001
From: Warner Losh <imp@FreeBSD.org>
Date: Mon, 28 Jun 2004 02:24:04 +0000
Subject: [PATCH] Allow dev to be NULL and assume that a device is not alive or
 not attached.

Reviewed by: njl(?) and jhb
---
 sys/kern/subr_bus.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c
index fd2e9d4b2068..10ad9094882a 100644
--- a/sys/kern/subr_bus.c
+++ b/sys/kern/subr_bus.c
@@ -1587,13 +1587,13 @@ device_is_enabled(device_t dev)
 int
 device_is_alive(device_t dev)
 {
-	return (dev->state >= DS_ALIVE);
+	return (dev != NULL && dev->state >= DS_ALIVE);
 }
 
 int
 device_is_attached(device_t dev)
 {
-	return (dev->state >= DS_ATTACHED);
+	return (dev != NULL && dev->state >= DS_ATTACHED);
 }
 
 int