WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

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
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcYKB3uMo0W7wKt1Qm6cTPwL0yaDHQAVV1ig
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

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel