Improve default machine type selection

[Andrea Bolognani]

On Thu, Apr 13, 2023 at 08:23:25AM -0600, Jim Fehlig wrote:
> On 4/6/23 08:27, Andrea Bolognani wrote:
> > On Thu, Apr 06, 2023 at 06:10:11AM -0700, Andrea Bolognani wrote:
> > > In conclusion, there currently doesn't seem to exist a way to define
> > > a useful integratorcp-based VM in libvirt, which IMO means we can
> > > safely change the default machine type for Arm architectures without
> > > any concerns about breaking existing VMs.
> > >
> > > I will look into whether the same can be said for RISC-V
> > > architectures. Hopefully that's the case.
> >
> > Yeah, the spike machine on RISC-V is unusable in basically the same
> > ways that the integratorcp machine is on Arm. Let's just change the
> > default to virt on all of those then :)
>
> Thanks for the confirmation. I should have time to work on this over the
> next days. I haven't looked in detail yet, but I get the feeling there is
> more to it than changing a few variables :-). Beyond code, do you have a
> mental checklist of the items that will need adjusted? E.g. docs, examples,
> tests, etc?

I might be excessively optimistic, but I truly believe it could be as
simple as changing a couple of lines in the QEMU driver :)

I don't think we rely on default machine types anywhere in the test
suite, and even if we were only minor touch-ups would probably be
necessary. And I don't think we mention them explicitly anywhere in
the documentation either.

Of course a NEWS entry for the change would be warranted, but that's
about it I think.

-- 
Andrea Bolognani / Red Hat / Virtualization