Re: [PATCH] target/ppc/cpu-models: Update max alias to power10

[Thomas Huth]

On 01/06/2022 10.38, Greg Kurz wrote:
> On Wed, 1 Jun 2022 09:27:31 +0200
> Thomas Huth <thuth@redhat.com> wrote:
>
> > On 31/05/2022 19.27, Murilo Opsfelder Araujo wrote:
> > > Update max alias to power10 so users can take advantage of a more
> > > recent CPU model when '-cpu max' is provided.
...
> We already have the concept of default CPU for the spapr
> machine types, that is usually popped up to the newer
> CPU model that is going to be supported in production.
> This goes with a bump of the machine type version as
> well for the sake of migration. This seems a lot more
> reliable than the "max" thingy IMHO.
>
> Unless there's a very important use case I'm missing,
> I'd rather kill the thing instead of trying to resurrect
> it.

It's about making ppc similar to other architectures, which
have "-cpu max" as well, see:

 https://gitlab.com/qemu-project/qemu/-/issues/1038

It would be nice to get something similar on ppc.

By the way, the warnings that you currently get when running with
TCG are quite ugly, too:

$ ./qemu-system-ppc64
qemu-system-ppc64: warning: TCG doesn't support requested feature, 
cap-cfpc=workaround
qemu-system-ppc64: warning: TCG doesn't support requested feature, 
cap-sbbc=workaround
qemu-system-ppc64: warning: TCG doesn't support requested feature, 
cap-ibs=workaround
qemu-system-ppc64: warning: TCG doesn't support requested feature, 
cap-ccf-assist=on

Maybe these could get fixed with a proper "max" CPU in TCG
mode, too?

 Thomas