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Date: Wed, 10 Jun 2009 18:52:38 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 05/11] qemu: MSI-X support functions
Message-ID: <20090610155238.GH28601@redhat.com>
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To: Paul Brook <paul@codesourcery.com>
Cc: Carsten Otte <cotte@de.ibm.com>, kvm@vger.kernel.org, Rusty Russell <rusty@rustcorp.com.au>, qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org, Blue Swirl <blauwirbel@gmail.com>, Christian Borntraeger <borntraeger@de.ibm.com>, Avi Kivity <avi@redhat.com>

On Wed, Jun 10, 2009 at 04:15:04PM +0100, Paul Brook wrote:
> > > That's seems just plain wrong to me.
> > > Loading a VM shouldn't not
> > > do anything that can't happen during normal operation.
> >
> > At least wrt pci, we are very far from this state: load just overwrites
> > all registers, readonly or not, which can never happen during normal
> > operation.
> 
> IMO that code is wrong. We should only be loading things that the guest can 
> change (directly or indirectly).
> 
> Paul

Making it work this way will mean that minor changes to a device can
break backwards compatibility with old images, often in surprising ways.
What are the advantages?

-- 
MST