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] "Iomem mapping not permitted" during windows crashdump u

To: "Tim Deegan" <Tim.Deegan@xxxxxxxxxx>, "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx>
Subject: RE: [Xen-devel] "Iomem mapping not permitted" during windows crashdump under GPLPV
From: "James Harper" <james.harper@xxxxxxxxxxxxxxxx>
Date: Wed, 3 Feb 2010 09:01:51 +1100
Cc: Paul Durrant <Paul.Durrant@xxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx, Jan Beulich <JBeulich@xxxxxxxxxx>
Delivery-date: Tue, 02 Feb 2010 14:02:17 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <20100202135820.GA7099@xxxxxxxxxxxxxxxxxxxxxxx>
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>
References: <4B681A31020000780002D2DD@xxxxxxxxxxxxxxxxxx> <C78DD987.8BC0%keir.fraser@xxxxxxxxxxxxx> <20100202135820.GA7099@xxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcqkD99ZB3hxBKwMQDWVvuQdqcJvZgAQu26w
Thread-topic: [Xen-devel] "Iomem mapping not permitted" during windows crashdump under GPLPV
> 
> No, the basic p2m code doesn't allow aliasing (because it tries to
> maintain a coherent m2p table).  The recent page-sharing patches from
> Grzegorz Milos relax that restriction, though IIRC only for explicit
> sharing operations managed by dom0.  I'm sure it could be extended to
> cover this case.
> 
> What's the problem with just ignoring the errors when a frontend page
> doesn't exist, though?
> 

It's mainly the noise. When I'm testing something and I get a crash, I
like to check 'xm dmesg' to see if my driver did anything stupid. During
some recent testing I was mapping an invalid page somewhere (due to
leaking grant refs and not detecting that I'd run out) which gave me a
bunch of errors in 'xm dmesg', including the ones caused by the crash
dump itself which confused things a bit.

At the end of the day though, a crash dump only occurs when something
has gone really wrong. Hibernation will have the same problems but there
are only a few cases where you would ever want to hibernate a DomU
anyway.

So if the solution is worse than the problem then I've got no objection
to leaving things as they are.

James


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

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