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] [Q] Is qemu used when we use VTd?

To: "Akio Takebe" <takebe_akio@xxxxxxxxxxxxxx>, "Jean Guyader" <jean.guyader@xxxxxxxxx>
Subject: RE: [Xen-devel] [Q] Is qemu used when we use VTd?
From: "Tian, Kevin" <kevin.tian@xxxxxxxxx>
Date: Fri, 12 Sep 2008 10:46:31 +0800
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Thu, 11 Sep 2008 19:47:13 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <48C90572.6020206@xxxxxxxxxxxxxx>
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: <48C8F6F2.20305@xxxxxxxxxxxxxx><f68b66460809110412q5b79e830h3b0658e37b0492e1@xxxxxxxxxxxxxx> <48C90572.6020206@xxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AckUBE/gvrUK3vIAQByOL0BuD5xqCAAfEeJw
Thread-topic: [Xen-devel] [Q] Is qemu used when we use VTd?
>From: Akio Takebe
>Sent: 2008年9月11日 19:48
>
>Can we directly use MMCONFIG for PCI-Express card 
>pass-throughed by VT-d on HVM?
>

You can't. MMCONFIG in no sense vary from old I/O port
style, as just a means to access PCI configuration space.
Note that PCI configuration space access has to be trapped
as it determines which devices, and also config space
content to be observed by HVM guest. Normally you'd need
some virtualization on config space content, such as BARs.
Thus even by presenting MMCONFIG capability to HVM
guest, you still need trap those access falling in that range.

Thanks,
Kevin

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