Re: [PATCH 3/3] x86: Switch to q35 as the default machine type

[Dr. David Alan Gilbert]

* Thomas Huth (thuth@redhat.com) wrote:
> On 16/02/2022 12.01, Dr. David Alan Gilbert wrote:
> > * Gerd Hoffmann (kraxel@redhat.com) wrote:
> > >    Hi,
> > > > Given the semantic differences from 'i440fx', changing the default
> > > > machine type has effects that are equivalent to breaking command
> > > > line syntax compatibility, which is something we've always tried
> > > > to avoid.
> > > 
> > > And if we are fine breaking backward compatibility I'd rather *not* pick
> > > a default, effectively making -M $something mandatory, similar to arm.
> > 
> > Oh, that's probably easy to do;  what are other peoples thoughts on
> > that?
> 
> I agree with Gerd. Getting rid of a default machine on x86 is likely better
> than silently changing it to q35. But I'd maybe say that this should go
> through the deprecation process first?

So just adding something like the following under 'System emulator
machines':

x86 default machine type
------------------------

x86 currently defaults to the very old ```pc``` machine type
which is based on the very old ```i440f``` chipset.  This default
will be removed and the user will be required to specify a machine
type explicitly using -M; users are encouraged to switch to the
not quite as old ```q35``` machine types.


(This option is going to take a lot more work switching all the
test cases over; in my world here I'd only changed the tests that broke
on q35, now everything is going to need to specify a type).

Dave



>  Thomas
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK