Removing VGA card panics the box on boot

[John Baldwin]

On Monday 15 November 2004 03:16 am, Ruslan Ermilov wrote:
> Hi there,
>
> I needed the unused PCI VGA card for testing another machine,
> so I pulled it out from my AlphaPC 164SX, and that gave me an
>
> instant panic on boot:
> : Timecounter "i8254" frequency 1193182 Hz quality 0
> : Timecounter "alpha" frequency 533183689 Hz quality 800
> : Timecounters tick every 0.976 msec
> : panic: mtx_lock() of spin mutex (null) @ /usr/src/sys/netinet/igmp.c:431
> : cpuid = 0
> : KDB: enter: panic
> : [thread 100004]
> : Stopped at      kdb_enter+0x48: or      zero,zero,zero  <zero=0x0>
> : db>
>
> Putting it back in results in normal behavior (no panic).
> Any hints?

Sounds like something is messing with free'd memory through a stale pointer 
and happens to be trashing that spin mutex as a result.  Not sure on how to 
track it down however.

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org