amd64+gdb -- instant reboot (BETA5 and 4)

[Mikhail Teterin]

> > Is this gdb misbehaviour a known problem? How can I have the system
> > avoid rebooting? Crash-dumping is enabled, but does not take place
> > :-(
> > 
> > Is that because timidity uses threads, perhaps?
[...] 
> It's definitely not known. Any chance you could hook up a serial
> console to log the output. It'll be pretty hard to debug otherwise.
> Sounds like you're likely getting a triple fault.

I'm not sure I can do this at all, and certainly, not this weekend. If
anyone already has a serial console set up, the problem should not be
difficult to reproduce in the following easy steps:

1) On a fresh 6.0-BETAX, install the audio/timidity++ port and try

	gdb timidity

2) Once in the debugger, run the program to play your favorite tune, such
as on downloaded from:

	http://www.fortunecity.com/tinpan/vanishing/189/themes/PinkPanther.mid

	(gdb) r /tmp/PinkPanther.mid

3) Interrupt the play by pressing Ctrl-C.
4) Try exiting the debugger... *BOOM*.

To save time, be sure to either unmount your filesystems or remount them
read-only. Thanks!

	-mi