From ba32f0ff83feb3d5846164437688ceebeec38c7e Mon Sep 17 00:00:00 2001
From: Warner Losh <imp@FreeBSD.org>
Date: Thu, 26 Mar 2009 17:36:19 +0000
Subject: [PATCH] Allow the attach routine to fail gracefully and not panic the
 system.

---
 sys/dev/ed/if_ed.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sys/dev/ed/if_ed.c b/sys/dev/ed/if_ed.c
index cbfabd2447fc..13a54682b5ff 100644
--- a/sys/dev/ed/if_ed.c
+++ b/sys/dev/ed/if_ed.c
@@ -389,7 +389,8 @@ ed_detach(device_t dev)
 		callout_drain(&sc->tick_ch);
 		ether_ifdetach(ifp);
 	}
-	bus_teardown_intr(dev, sc->irq_res, sc->irq_handle);
+	if (sc->irq_res != NULL && sc->irq_handle)
+		bus_teardown_intr(dev, sc->irq_res, sc->irq_handle);
 	ed_release_resources(dev);
 	ED_LOCK_DESTROY(sc);
 	bus_generic_detach(dev);