Re: P4/i845 Strange clock drifting

Zwane Mwaikambo (zwane@linux.realnet.co.sz)
Fri, 5 Apr 2002 16:31:02 +0200 (SAST)


On Fri, 5 Apr 2002, Chris Wilson wrote:

> > -dj2 P4 thermal patch is a bit broken (my bad), but the fact that it
> > doesn't detect an APIC means that code would, erm do interesting things...
>
> <grin>
>
> I've now tried a couple more kernels to no avail - nothing can find APICs.
> Is it even possible for a P4 to not have a local APIC? System is a
> supermicro 5012B*.
>
> /proc/cpuinfo shows:
>
> flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm
>
> (notice no "apic"). Is this normal/correct? If just just removed the check
> from apic.c and tried to enable the apic anyway then are bad things going
> to happen?

All P4s have a local APIC, however your bios can play a part in making it
unavailable (global enable flag in apic base MSR). Please send me your
dmesg.

> I've also noticed [probably unrelated but...] that I can't reboot the box
> without use of the reset button - it doesn't come up after /sbin/reboot -f
> either. It's at a colo facility so I can't see what's being displayed
> until I find out a null modem and go for a drive... :)

Have you tried the various reboot kernel parameters? You can try the
following.

reboot=w - Sets warm reboot flag
reboot=c - Sets cold reboot flag
reboot=b - Reboot via jump to BIOS

and finally if you're really desperate ;)

reboot=h - do a hard reboot, i think this is does a triple fault

Cheers,
Zwane

-- 
http://function.linuxpower.ca
		

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