RE: [Xen-devel] Bad clock ticking in xen0

To:	"Tomas Kouba" <tomas@xxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject:	RE: [Xen-devel] Bad clock ticking in xen0
From:	"Ian Pratt" <m+Ian.Pratt@xxxxxxxxxxxx>
Date:	Mon, 26 Dec 2005 20:56:48 -0000
Delivery-date:	Mon, 26 Dec 2005 21:00:36 +0000
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Thread-topic:	[Xen-devel] Bad clock ticking in xen0

> (XEN) Local APIC disabled by BIOS -- you can enable it with "lapic"
> (XEN) Local APIC not detected. Using dummy APIC emulation
> 
> are a bit strange for me. The BIOS is quite simple 
> PheonixBIOS with no options regarding APIC.
> lapic kernel parameter was *surely* used

It's not that uncommon for the bios to disable the apic. I suppose it's
possible that Duron's don't have one anyway.

One thing that might be worth doing is to write a little program that
sits in a loop calling gettimeofday and reporting the delta from the
previous call [hint: convert the output into a 64b long long by
u.tv_usec + (unsigned long long)u.tv_sec*1000000; ]

It'll be interesting to see whether time runs forward smoothly or jumps
ahead in steps.

If time is progressing smoothly, then I guess the problem with your
laptop must be that the PIT that Xen uses is being subverted by
something else. No idea what, though -- perhaps something hidden in SMM.

Ian

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