kern/156198: loading snd_hda kernel module hangs system

[Kyle Dassoff]

>Number:         156198
>Category:       kern
>Synopsis:       loading snd_hda kernel module hangs system
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Apr 05 15:30:10 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Kyle Dassoff
>Release:        8.2-RELEASE-p0
>Organization:
>Environment:
FreeBSD bigkahuna.kd 8.2-RELEASE FreeBSD 8.2-RELEASE #0: Thu Feb 17 02:41:51 UTC 2011     root at mason.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  amd64

>Description:
When attempting to load the snd_hda module, the system becomes completely unresponsive and the screen blanks. The only action available is to hard reboot the system with the power button.

Loading the sound module alone causes no problems. This occurs with or without X running or drm (radeon in my case) modules loaded.
>How-To-Repeat:
[sudo] kldload snd_hda

Happens consistently on my machine.
>Fix:
None. Must reboot using the power button (holding down to force a reboot) or switch.

>Release-Note:
>Audit-Trail:
>Unformatted: