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Date: Mon, 15 Oct 2018 06:27:21 -0400
From: "Michael S. Tsirkin" <mst@redhat.com>
Message-ID: <20181015062543-mutt-send-email-mst@kernel.org>
References: <20181013025435.25785-1-ehabkost@redhat.com>
	<20181015081641.q6r5wnhm7rq5tgfh@sirius.home.kraxel.org>
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In-Reply-To: <20181015081641.q6r5wnhm7rq5tgfh@sirius.home.kraxel.org>
Subject: Re: [Qemu-devel] [PATCH] virtio: Provide version-specific variants
 of virtio PCI devices
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To: Gerd Hoffmann <kraxel@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>, qemu-devel@nongnu.org, Gonglei <arei.gonglei@huawei.com>, Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= <philmd@redhat.com>, Wainer dos Santos Moschetta <wainersm@redhat.com>, Cleber Rosa <crosa@redhat.com>, Markus Armbruster <armbru@redhat.com>, Laine Stump <laine@redhat.com>, Caio Carrara <ccarrara@redhat.com>

On Mon, Oct 15, 2018 at 10:16:41AM +0200, Gerd Hoffmann wrote:
> On Fri, Oct 12, 2018 at 11:54:35PM -0300, Eduardo Habkost wrote:
> > The current virtio-*-pci device types actually represent 3
> > different types of devices:
> > * virtio 1.0 non-transitional devices
> > * virtio 1.0 transitional devices
> 
> Ok.
> 
> > * virtio 0.9 ("legacy device" in virtio 1.0 terminology)
> 
> Why?  Is there any reason to prefer 0.9 over transitional?
> 
> cheers,
>   Gerd

Right - maybe a flag to disable modern interface is enough.
We thus get two types:
- transitional (legacy)
- non-transitional (modern)
which matches spec nicely.

-- 
MST