From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [PATCH] Dom0 Kernel - Fixes for
	saving/restoringMSI/MSI-X across Dom0 S3
Date: Mon, 24 Nov 2008 12:03:37 +0000
Message-ID: <C5504899.2950B%keir.fraser@eu.citrix.com>
References: <492AA0F0.76E4.0078.0@novell.com>
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To: Jan Beulich <jbeulich@novell.com>, Haitao Shan <haitao.shan@intel.com>
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On 24/11/08 11:41, "Jan Beulich" <jbeulich@novell.com> wrote:

>>>> "Shan, Haitao" <haitao.shan@intel.com> 24.11.08 12:03 >>>
>> With this patch, MSI/MSI-X capabilities and tables are saved in Dom0 when
>> S3 and restored when resume. Actually, this is also the approach that
>> kernel takes. The only concern is that Dom0 should not touch MSI/MSI-X,
>> they are owned by VMM itself. Maybe adding a hypercall to instruct Xen to
>> do the saving/restoring is good. I wonder whether the reason is strong
>> enough for adding a hypercall for such purpose.
> 
> Is it at all necessary to use a hypercall here? Shouldn't Xen itself be able
> to
> do the necessary saving/restoring (just like it does for IO-APIC)?

I was thinking the same thing. Haitao: shall I hold off on your original
patch while we think about this?

 -- Keir