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

[Xen-devel] Re: [PATCH 0/2] passthrough: make management of PCI D-states

To: Kouya Shimura <kouya@xxxxxxxxxxxxxx>
Subject: [Xen-devel] Re: [PATCH 0/2] passthrough: make management of PCI D-states by guest optional
From: Yuji Shimada <shimada-yxb@xxxxxxxxxxxxxxx>
Date: Fri, 06 Mar 2009 16:40:13 +0900
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Ian Jackson <Ian.Jackson@xxxxxxxxxxxxx>
Delivery-date: Thu, 05 Mar 2009 23:41:19 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <7kfxhrfcmv.fsf@xxxxxxxxxxxxxxxxxxxxxxxxxx>
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: <7kfxhrfcmv.fsf@xxxxxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
On Fri, 6 Mar 2009 14:23:20 +0900
Kouya Shimura <kouya@xxxxxxxxxxxxxx> wrote:

> Using D3hot state of PCI devices in xen is not mature yet.
> I met domain destruction/creation troubles in some PCI cards since the
> PCI config registers can't be read with D3hot state. xend.log is attached.

xend.log shows error occurred on resetting the device.
I think programming the device to D0 state is needed before resetting
the device.

In addition to this, config register values should be saved
when domain 0 starts, because in some devices config registers
can't be read with D3 hot state. To achieve this, it is good that
pciback driver saves config register values when it is bound to the
device, resets the device, and restores config register after
resetting.

Actually resetting and saving/restoring in pciback were discussed on
xen-devel. But unfortunately they seem not to be under developing.

Another approach is that qemu programs the device to D0 state on
shutdowning of guest domain, instead of booting of guest domain.
Then, xend can reset device successfully.

Thanks,
--
Yuji Shimada

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