2.6 kernel won't reboot on AMD system

2.6 kernel won't reboot on AMD system

[David N. Welton]

[ Please CC replies to me. ]

Before you hit 'reply', no, I'm not talking about the machine not 
getting past the BIOS check complaining that there is no keyboard present.

Kernel 2.6.7

model name      : AMD Athlon(tm) XP 2400+

motherboard: http://www.ecsusa.com/products/km400-m2.html

... not sure what else might be useful... apci=off added to boot 
options.  Preemptive kernel.

In any case, the machine in question does not reboot.  I traced the 
problem down to the mach_reboot but it doesn't get past those assembly 
instructions.  Things do seem to work alright if a keyboard is 
installed.  Otherwise, the machine just sits there, no longer responsive 
to pings or anything else.

This appears to be a somewhat common problem, as I found several other 
posters discussing it:

http://lkml.org/lkml/2004/3/12/248

http://marc.theaimsgroup.com/?l=linux-kernel&m=108868695814658&w=2

any ideas on what parts of the kernel to look at in order to determine 
what is causing this?

Thankyou,
-- 
David N. Welton
davidw@eidetix.com