kern/45862: Additional hdaudio/mixer kernel crash info

[bch%methodlogic.net@localhost]

>Number:         45862
>Category:       kern
>Synopsis:       more hdaudio/mixer failure data in -current
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Jan 20 16:55:00 +0000 2012
>Originator:     bch%methodlogic.net@localhost
>Release:        NetBSD 5.99.60
>Organization:
        Method Logic Digial
        http://methodlogic.net/
>Environment:
System: NetBSD kamloops 5.99.60 NetBSD 5.99.60 (kamloops) #40: Fri Jan 19 
20:59:12 PDT 2010 root@kamloops:/usr/obj/sys/arch/amd64/compile/kamloops amd64
Architecture: x86_64
Machine: amd64
>Description:
        Kernel crash in mixer on boot w/ DEBUG kernel

        Transcribed:

Detecting hardware...panic: kmem_free(0xffff80004d6b3008, 12) != allocated size 
16409
fatal breakpoint trap in supervisor mode
trap type 1 code 0 rip ffffffff8022e915 cs 8 rflags 246 cr2 0 cpl 0 rsp 
ffff80004d691a40
Stopped in pid 0.44 (system) at netbsd:breakpoint+0x5: leave
db{0}> 


I've been having hdaudio/mixer issues for months, but this is the first time 
I've run w/ a debug kernel -- I don't have the prev. PR, but will combine these 
(seems appropriate) when I do. I do want to get this out as yet another 
datapoint though, as this flaky audio/mixer behaviour has been going on for 
some time.
>How-To-Repeat:
        Run DEBUG -current kernel on Thinkpad T410.
>Fix: