I'm using the stock Fedora Core 1 kernel.  About 15 minutes ago, I was
playing Nobunaga's Ambitions (super nintendo game) under the zsnes
emulator, when it suddenly froze and the caps and scroll lock lights
started blinking.  I powered off, powered back on and then found the
following in my /var/log/messages as the last things before the
messages about the machine starting up again:

Nov 30 16:37:28 Eenie kernel: Assertion failed! chan->is_active ==
sg_active(chan->iobase),via82cxxx_audio.c,via_chan_maybe_start,line=1388
Nov 30 16:38:04 Eenie last message repeated 7 times

with several more repeats.  However, I don't think this was actually
related to the kernel panic as I have found lots of similar messages
in /var/log/messages.[123]

Also, I don't know if this is relevant or not, but I had another
problem about an hour ago requiring me to reboot the system (I'm
starting to suspect hardware failure or something, because this
machine usually doesn't give me problems).  That was not a hard freeze
(i.e., I was able to log in remotely from another machine on the LAN
and tell the machine to reboot itself), but I did find the following
in my /var/log/messages that might be related (note that at that time
I had been reading my email in evolution with a couple other processes
such as Mozilla running as well):

Nov 30 16:11:26 Eenie kernel: Unable to handle kernel paging request
at virtual address a13d9dd4

I then got all kinds of debugging output spewed to my logs associated
with this and it seemed to repeat several times.  I'll attach my
/var/log/messages file with it all (only 62K, since logrotate recently
rolled things over).  I didn't find any similar errors to this in
/var/log/messages.[1234].

I have no clue what any of this really means nor do I know how to
reproduce any of it.  If I find a way, I'll let you know.  Hopefully
the info I provided is useful in some way.  Let me know if there's any
other information I can provide.