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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] Snapshots not bound to an architecture?
Date: Tue, 7 Oct 2008 21:30:07 +0100
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To: qemu-devel@nongnu.org

On Tuesday 07 October 2008, Anthony Liguori wrote:
> Blue Swirl wrote:
> > Hi,
> >
> > While testing the savevm/loadvm functions, I noticed that it's
> > possible to attempt to load a snapshot made for entirely different
> > architecture. There are a lot of warnings, of course.
> >
> > Could we prevent this somehow? Or is there a use case for this, for
> > example loading a snapshot made on i386 to an x86_64 emulator?
>
> I think we should introduce a machine section for save/restore that
> included that information.  It should also be versioned in such a way
> that it could be incremented whenever a new piece of hardware is added
> to the default machine type.

Using a single version number to determine the "base" machine is IMHO a bad 
idea. The base peripherals should be identified (and mismatches detected) 
that same way as any other peripherals.

The simplest way to avoid loading the wrong type of machine is to give the 
cpus different names (e.g. cpu_i386/cpu_amd64) instead of just calling 
them "cpu".

Paul