Subject: Re: new machine won't reboot automatically
To: Brad Parker <>
From: Mark P. Gooderum <>
List: current-users
Date: 10/03/1994 18:36:02
According to Brad Parker:
> I can't get one of my new 486/33 machines to reboot.  It hangs after
> printing the "Rebooting..." message.  Other than this it works quite
> well.

My machine went through a similar wouldn't reboot, a hardware
reset or a halt followed by pressing a key, would work...then the 
problem went away some time in July.

I've seen a related problem that I forgot to mention that existed in
current at least up to yesterdays changes (I haven't rebuilt yet
since).  If you do a reboot in single user mode, the shell exits, init
prints the changing state 0 to state 1 message, and then the machine

> [486/33, 256k cache, 16mb, ide controller, VLB vga controller, 2 x 515mb
> ide disks, 2 x ethernet cards, 1 sync serial card]
> This machine, unlike the others I have, does *not* have an AMI bios.
> (just in case that matters - from looking at cpu_reset(), I don't
> think it should)

It could, the reboot vector basically jumps into the could be
something is in a state that one BIOS doesn't like that another will
tolerate (warm boots don't toggle the hardware reset lines if 
I remember...).

> anyone else seen this have have any ideas?  the cpu is a stock intel 486DX.

I've got source to a PC utility called "bootany" that gives you a menu
to select between a warm boot and a cold reset, it might be an interesting
option to allow, that a reboot does a cold instead of a warm restart.
It probably wouldn't be hard to integrate and might be a win, especially
for a reboot after a panic where there may be scrambled peripheral boards.
> if I hit the reset button it's fine.

This basically forces a hardware reset of the whole system very similar
to what a power on cycle does.  *Almost* nothing can screw this up...a 
few things can, but most of those that can also scramble a power cycle
restart too (trashing the CMOS ram, etc).
Mark P. Gooderum			   USSnail:  Good Creations
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