Re: [Qemu-devel] KVM call minutes for Feb 8

Scott Wood
2011-02-10T19:45:15Z

On Thu, 10 Feb 2011 19:22:38 +0000
Peter Maydell <peter.maydell@linaro.org> wrote:

> On 10 February 2011 19:17, Scott Wood <scottwood@freescale.com> wrote:
> > On Thu, 10 Feb 2011 08:16:15 +0000
> > Peter Maydell <peter.maydell@linaro.org> wrote:
> >> On 10 February 2011 07:47, Anthony Liguori <anthony@codemonkey.ws> wrote:
> >> > So very concretely, I'm suggesting we do the following to target-i386:
> >>
> >> > 2) get rid of the entire concept of machines.  Creating a i440fx is
> >> > essentially equivalent to creating a bare machine.
> >>
> >> Does that make any sense for anything other than target-i386?
>
> > It makes a lot of sense for us on powerpc.  Maybe it has to do with a
> > longer tradition of using device trees versus opaque machine IDs -- I don't
> > think the hardware itself makes any substantial difference.  Currently we
> > end up having everything pretend to be an mpc8544ds (with some differences
> > described by the guest device tree that the user feeds in), which is ugly.
>
> Hmm. Device tree is coming to ARM, but just at the moment it's
> generally one-kernel-one-machine still. (We've only just gained the
> ability to compile one kernel for both UP and SMP...)
>
> I kind of think you're still defining a "machine", you're just doing it
> in your device tree blob rather than in C.

Right, that's the point -- the definition is just a definition, it's not
tied up with implementation. This reduces the amount of duplication in
implementation (or inappropriate sharing, as in the "use mpc8544ds for
all 85xx" case).

-Scott