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Date: Wed, 10 Oct 2018 11:59:53 +0200
From: "Hoffmann, Gerd" <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2] vhost-user: define conventions for
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To: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau <marcandre.lureau@redhat.com>
Cc: =?utf-8?Q?J=C3=A1n?= Tomko <jtomko@redhat.com>, qemu-devel <qemu-devel@nongnu.org>, "Kaplansky, Victor" <victork@redhat.com>, "Michael S . Tsirkin" <mst@redhat.com>, libvir-list <libvir-list@redhat.com>, "Dr. David Alan Gilbert" <dgilbert@redhat.com>, "Coquelin, Maxime" <maxime.coquelin@redhat.com>, Gonglei <arei.gonglei@huawei.com>, Felipe Franciosi <felipe@nutanix.com>, "Liu, Changpeng" <changpeng.liu@intel.com>

On Sat, Oct 06, 2018 at 02:32:45AM +0400, Marc-Andr=E9 Lureau wrote:
> Hi
>=20
> On Fri, Oct 5, 2018 at 7:59 PM Hoffmann, Gerd <kraxel@redhat.com> wrote=
:
> >
> >   Hi,
> >
> > > For example, "virgl" support may not be implemented. This
> > > --print-capabilities is a simple way to check what the backend
> > > implements.
> >
> > What is the expected behavior in case virgl is implemented by the
> > backend, but not available (due to lack of 3d hardware in the host fo=
r
> > example) ?
>=20
> I would say either it fails at runtime, or the backend doesn't announce=
 it.
>=20
> Would you want something else?

Yes, one of the two, but we should clarify which one.

I suspect "fail at runtime" is easier for libvirt, given that it libvirt
must handle backend failures anyway ...

cheers,
  Gerd