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From: Rusty Russell <rusty@rustcorp.com.au>
To: "Michael S. Tsirkin" <mst@redhat.com>
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Subject: Re: [PATCHv3 RFC] virtio-pci: flexible configuration layout
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Date: Wed, 30 Nov 2011 09:58:45 +1030
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On Mon, 28 Nov 2011 10:41:51 +0200, "Michael S. Tsirkin" <mst@redhat.com> wrote:
> On Mon, Nov 28, 2011 at 11:25:43AM +1030, Rusty Russell wrote:
> > > > But I'm *terrified* of making the spec more complex;
> > > 
> > > All you do is move stuff around. Why do you think it simplifies the spec
> > > so much?
> > 
> > No, but it reduces the yuk factor.  Which has been important to adoption.
> 
> Sorry if I'm dense. Could you please clarify: do you think we can live
> with the slightly higher yuk factor assuming the spec moves the
> legacy mode into an appendix as you explain below and driver has a
> single 'legacy' switch?

Yep, it's all a trade-off.  A clean slate is good, but if we can make
our lives in transition less painful, I'm all for it.

> I think I see a way to do that in a relatively painless way.
> Do you prefer seeing driver patches or spec? Or are you not interested
> in reusing the same structure at all?

I think we should look at code at this point; my gut says we're going to
be not-quite-similar-enough-to-be-useful.  At which point, a clean-slate
approach is more appealing.  But the code will show, one way or another.

Thanks,
Rusty.