From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 16/22] virtio_pci: use separate notification offsets for
	each vq.
Date: Wed, 27 Mar 2013 07:21:42 -0700
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To: "Michael S. Tsirkin" <mst@redhat.com>
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We probably shouldn't given the requirement for PCIe devices to be able to operate without configured I/O BARs.

On the other hand what about a host which can only virtualize I/O for some reason... not sure if that is a realistic scenario.

"Michael S. Tsirkin" <mst@redhat.com> wrote:

>On Tue, Mar 26, 2013 at 07:31:31PM -0700, H. Peter Anvin wrote:
>> On 03/26/2013 05:22 PM, H. Peter Anvin wrote:
>> > I would say let it be undefined... in most cases the host will know
>what device(s) will matter; e.g. if the guest is ppc no point in
>providing an I/O BAR.
>> 
>> For pluggable physical devices, though, both should be provided.
>> 
>> 	-hpa
>
>Yes but what Rusty asked, is whether we should make the memory BAR
>optional.
>
>> -- 
>> H. Peter Anvin, Intel Open Source Technology Center
>> I work for Intel.  I don't speak on their behalf.

-- 
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