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] determining if a backend device is not working

To: James Harper <james.harper@xxxxxxxxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] determining if a backend device is not working
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Tue, 10 Mar 2009 08:23:45 +0000
Cc:
Delivery-date: Tue, 10 Mar 2009 01:24:10 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <AEC6C66638C05B468B556EA548C1A77D0162CB5B@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/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcmhIgybbc5MxlDyS1KuqiEOxhybGAAN3qkJ
Thread-topic: [Xen-devel] determining if a backend device is not working
User-agent: Microsoft-Entourage/12.15.0.081119
On 10/03/2009 01:46, "James Harper" <james.harper@xxxxxxxxxxxxxxxx> wrote:

> In my gplpv drivers, the best I have come up with to determine if the
> backend is not working is to wait for a few seconds (30 currently), and
> if the backend state hasn't changed by then then I assume that it's
> broken.
> 
> Is there a better way? The situation where this comes up is when
> something like ',hdc:cdrom,r' is specified in the config file.
> 
> Even though I set all of the frontend up, the backend just stays at
> state 2 instead of transitioning to 4.

I think we expect backends to always be responsive. So we have no model for
what to do if that assumption breaks. Your particular example above sounds
like a weird backend bug?

 -- Keir



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