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From: Marcel Apfelbaum <marcel@redhat.com>
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Date: Fri, 22 Jul 2016 10:55:10 +0300
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Subject: Re: [Qemu-devel] [PATCH V3] hw/virtio-pci: fix virtio behaviour
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To: "Michael S. Tsirkin" <mst@redhat.com>, Gerd Hoffmann <kraxel@redhat.com>
Cc: qemu-devel@nongnu.org, cornelia.huck@de.ibm.com, Greg Kurz <gkurz@linux.vnet.ibm.com>

On 07/22/2016 01:21 AM, Michael S. Tsirkin wrote:
> On Thu, Jul 21, 2016 at 11:58:52PM +0200, Gerd Hoffmann wrote:
>>    Hi,
>>
>>> Actually this can still break existing scripts:
>>> stick a device on express bus but add disable-modern=on
>>> Gave you a legacy device previously but it no longer does.
>>
>> Unlikely to happen in practice because there is little reason to use
>> disable-modern=on in 2.6 & older because that is the default ...
>
> Good point, I forgot.
>
>> Still we can default to legacy=yes in case disable-modern=on +
>> disable-legacy=auto.
>
> Given the above I'm not sure it's worth it. I'll leave it to Marcel
> to decide.

Hi Michael,Gerd,

I think it doesn't worth to make the code more complicated
for an uninteresting scenario.

>
>>   And throw and error in case both modern and legacy
>> are explicitly disabled (as already suggested elsewhere in this thread).
>>

There is already a patch for this upstream:
https://lists.gnu.org/archive/html/qemu-devel/2016-07/msg05263.html

Michael, since the rc1 is approaching fast, can you please advice
on what changes to make to the commit message and if you prefer me
to add the Greg patch to the series and re-send, or you can take it separately?

Thanks,
Marcel


>> cheers,
>>    Gerd