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


Re: [Xen-devel] shutdown question - PV vs HVM

To: James Harper <james.harper@xxxxxxxxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] shutdown question - PV vs HVM
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Mon, 01 Oct 2007 06:28:17 +0100
Delivery-date: Sun, 30 Sep 2007 22:24:32 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <AEC6C66638C05B468B556EA548C1A77D01249944@trantor>
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: AcgDyFItoNtfu9ELRKK7OSZX/N5DVwAI4ycS
Thread-topic: [Xen-devel] shutdown question - PV vs HVM
User-agent: Microsoft-Entourage/
For a PV guest, a shutdown node is written into xenstore which the guest
picks up. The guest will then usually initiate a clean shutdown.

The same happens for an HVM guest with PV drivers installed. If an HVM guest
has no PV drivers (And so will obviously not be watching xenstore) then xend
notifies the shutdown immediately to Xen. This causes Xen to immediately
transition the guest to shutdown state, and no longer execute the guest,
with no chance for clean shutdown. If there are no PV drivers installed,
clean shutdown needs to be initiated from within the guest.

 -- Keir

On 1/10/07 02:13, "James Harper" <james.harper@xxxxxxxxxxxxxxxx> wrote:

> I've had a bit of a look through the code but can't seem to find the
> answer to this question... what is the method by which 'xm' tells a
> domain to shutdown?
> What is different about HVM that means it just powers straight off?
> Looking at the Linux source, it appears that something is done with
> 'platform-feature-multiprocessor-suspend' in the store, but it isn't
> clear to me what...
> Thanks
> James
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel

Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>