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Date: Wed, 16 Nov 2011 09:21:38 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Rusty Russell <rusty@rustcorp.com.au>
Cc: Sasha Levin <levinsasha928@gmail.com>,
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Subject: Re: [PATCHv2 RFC] virtio-spec: flexible configuration layout
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On Wed, Nov 16, 2011 at 10:28:52AM +1030, Rusty Russell wrote:
> On Fri, 11 Nov 2011 09:39:13 +0200, Sasha Levin <levinsasha928@gmail.com> wrote:
> > On Fri, Nov 11, 2011 at 6:24 AM, Rusty Russell <rusty@rustcorp.com.au> wrote:
> > > (2) There's no huge win in keeping the same layout.  Let's make some
> > >    cleanups.  There are more users ahead of us then behind us (I
> > >    hope!).
> > 
> > Actually, if we already do cleanups, here are two more suggestions:
> > 
> > 1. Make 64bit features a one big 64bit block, instead of having 32bits
> > in one place and 32 in another.
> > 2. Remove the reserved fields out of the config (the ones that were
> > caused by moving the ISR and the notifications out).
> 
> Yes, those were exactly what I was thinking.  I left it vague because
> there might be others you can see if we're prepared to abandon the
> current format.
> 
> Cheers,
> Rusty.

Yes but driver code doesn't get any cleaner by moving the fields.
And in fact, the legacy support makes the code messier.
What are the advantages?

-- 
MST