[Qemu-devel] Re: [PATCH 1/3] Make kvm64 the default cpu model when kvm_enabled()

[Anthony Liguori]

On 10/07/2010 03:42 AM, Roedel, Joerg wrote:
> On Wed, Oct 06, 2010 at 03:24:59PM -0400, Anthony Liguori wrote:
>    
> > > > +    qemu_compat_version = machine->compat_version;
> > > > +
> > > >        if (display_type == DT_NOGRAPHIC) {
> > > >            if (default_parallel)
> > > >                add_device_config(DEV_PARALLEL, "null");
> > > > --
> > > > 1.7.0.4
> > > >
> > > >          
> > > Looks fine to me, given CPUs are not in qdev. Anthony?
> > >
> > >        
> > The idea is fine, but why not just add the default CPU to the machine
> > description?
> >      
> If I remember correctly the reason was that the machine description was
> not accessible in the cpuid initialization path because it is a function
> local variable.

Not tested at all but I think the attached patch addresses it in a 
pretty nice way.

There's a couple ways you could support your patch on top of this.  You 
could add a kvm_cpu_model to the machine structure that gets defaulted 
too if kvm_enabled().  You could also introduce a new KVM machine type 
that gets defaulted to if no explicit machine is specified.

>   I could have made it a global variable but considered
> the compat_version approach simpler. The qemu_compat_version might also
> be useful at other places.
>    

The reason we've avoided having a builtin notion of versions is that we 
have many downstreams where versioning would get very complicated.  If 
we stick to features it makes it much easier for downstreams.

Regards,

Anthony Liguori

>         Joerg
>
>

0001-machine-make-default-cpu-model-part-of-machine-struc.patch
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