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] [PATCH] [VTD] Remove PCI device enumeration for dom0 in

To: "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx>, "Espen Skoglund" <espen.skoglund@xxxxxxxxxxxxx>
Subject: RE: [Xen-devel] [PATCH] [VTD] Remove PCI device enumeration for dom0 in Xen
From: "Han, Weidong" <weidong.han@xxxxxxxxx>
Date: Wed, 22 Oct 2008 21:15:13 +0800
Cc: "Zhao, Yu" <yu.zhao@xxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx, "Kay, Allen M" <allen.m.kay@xxxxxxxxx>
Delivery-date: Wed, 22 Oct 2008 06:15:39 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <C524DE97.28520%keir.fraser@xxxxxxxxxxxxx>
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: <18687.7900.317457.856048@xxxxxxxxxxxxxxxxxx> <C524DE97.28520%keir.fraser@xxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: Ack0Q9W6E/5VMqA3Ed2kCAAX8io7RQAA06og
Thread-topic: [Xen-devel] [PATCH] [VTD] Remove PCI device enumeration for dom0 in Xen
Keir Fraser wrote:
> On 22/10/08 13:38, "Espen Skoglund" <espen.skoglund@xxxxxxxxxxxxx>
> wrote: 
> 
>>> Xen 3.3 should continue to work with older dom0 kernels. However,
>>> now that iommu is *disabled* by default, will this mean that it
>>> would continue to work with older dom0 kernels so long as iommu is
>>> not enabled on the Xen command line? This should be tested and
>>> confirmed with this patch applied.  If so, I would accept it.
>> 
>> Users of pci_lock_pdev() and pci_lock_domain_pdev() would not be able
>> to find the PCI device unless it has been registered by dom0.  Apart
>> from the iommu code, the only user affected would be the MSI code
>> which looks up the PCI device before enabling MSIs on it.  As such,
>> you would not be able to enable MSIs if you have an old dom0 kernel.
> 
> Is there any disadvantage to keeping this legacy code in Xen, apart
> from it annoyingly sitting there?
> 

 At present, I don't see any other disadvantage on functionality, apart
from it annoyingly sitting there and it allocates two pdev for the same
bdf.

Regards,
Weidong


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