From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [PATCH][RFC] Support S3 for MSI interrupt in latest
	kernel dom0
Date: Wed, 17 Dec 2008 15:06:49 +0000
Message-ID: <C56EC609.20544%keir.fraser@eu.citrix.com>
References: <49491F2B.76E4.0078.0@novell.com>
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To: Jan Beulich <jbeulich@novell.com>
Cc: Yunhong Jiang <yunhong.jiang@intel.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
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On 17/12/2008 14:47, "Jan Beulich" <jbeulich@novell.com> wrote:

>> Could Xen remember the MSI state automatically, as it does for IO-APIC
>> presumably already? It knows what vectors are routed where at least, even if
>> dom0 has to reprogram the PCI device itself.
> 
> That is what the map_guest_pirq() re-invocation is intended for - use the
> already known (stored) MSI state to re-setup the device accordingly
> (after all, msi_compose_msg() only depends on the vector information
> to be able to reconstruct address and data fields).

Why wait for map_guest_pirq() to be invoked to do this?

 -- Keir