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From: Rusty Russell <rusty@rustcorp.com.au>
To: Sasha Levin <levinsasha928@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>,
        lkml - Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Alexey Kardashevskiy <aik@ozlabs.ru>, Amit Shah <amit.shah@redhat.com>,
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        Wang Sheng-Hui <shhuiw@gmail.com>,
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Subject: Re: [PATCHv3 RFC] virtio-pci: flexible configuration layout
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References: <20111122183621.GA5235@redhat.com> <87hb1v1scp.fsf@rustcorp.com.au> <20111123084640.GE22734@redhat.com> <87ty5uxso3.fsf@rustcorp.com.au> <20111124070728.GH29994@redhat.com> <87vcq5t69c.fsf@rustcorp.com.au> <1322471731.3577.10.camel@lappy>
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Date: Wed, 30 Nov 2011 10:10:22 +1030
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On Mon, 28 Nov 2011 11:15:31 +0200, Sasha Levin <levinsasha928@gmail.com> wrote:
> On Mon, 2011-11-28 at 11:25 +1030, Rusty Russell wrote:
> > I'd like to see kvmtools remove support for legacy mode altogether,
> > but they probably have existing users.
> 
> While we can't simply remove it right away, instead of mixing our
> implementation for both legacy and new spec in the same code we can
> split the virtio-pci implementation into two:
> 
> 	- virtio/virtio-pci-legacy.c
> 	- virtio/virtio-pci.c
> 
> At that point we can #ifdef the entire virtio-pci-legacy.c for now and
> remove it at the same time legacy virtio-pci is removed from the kernel.

Hmm, that might be neat, but we can't tell the driver core to try
virtio-pci before virtio-pci-legacy, so we need detection code in both
modules (and add a "force" flag to virtio-pci-legacy to tell it to
accept the device even if it's not a legacy-only one).

Then it should work...
Cheers,
Rusty.