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/
Home Products Support Community News


[Xen-devel] dom0 and apicid not equal to cpuid

To: xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-devel] dom0 and apicid not equal to cpuid
From: "Langsdorf, Mark" <mark.langsdorf@xxxxxxx>
Date: Fri, 8 Feb 2008 15:05:44 -0600
Delivery-date: Fri, 08 Feb 2008 13:11:45 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
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: Achqll4p+tddFVOYTAK5v3h066MrkQ==
Thread-topic: dom0 and apicid not equal to cpuid
Some AMD processor systems assign the boot processor
(cpu 0) to apicid 4.  Standard Linux handles this
cleanly by keeping track of the correspondences amongst
cpu id, apic id, and acpi id.  dom0 Xen does not have
the code to do that, and AMD is seeing some strange
behavior on our 4 socket quad-core systems.

Specifically, when we try to get ACPI information for
cpu 0, the correspondences break down and the request

I know some of the code needs to be added to mpparse-xen.c,
but it looks like the relevant code was #ifdef'd out in
the first place.  Does anyone know why the code to match
cpuids to apicids was removed and what would need to be
done to restore it?

-Mark Langsdorf
Operating System Research Center

Xen-devel mailing list