Re: [Qemu-devel] [PATCH v3 2/2] Add configure option --enable-pc-1-0-qemu-kvm

[Markus Armbruster <armbru@redhat.com>]

Alex Bligh <alex@alex.org.uk> writes:

> On 22 Sep 2014, at 16:45, Andreas Färber <afaerber@suse.de> wrote:
>
>> What about adding a bool property "qemu-kvm-compat" to the MachineClass?
>> Then a qemu-kvm shell script (like SUSE uses) can pass -global
>> machine.qemu-kvm-compat=on whereas qemu-system-x86_64 would run in the

No need to mess with -global, just use -machine qemu-kvm-compat=off.
You can have multiple -machine, and the last key=value wins.

>> default non-qemu-kvm mode (config on disk would affect both). It would
>> also allow running -machine pc-0.15,qemu-kvm-compat=on, ditching lots of
>> new machine names and avoiding the name bikeshedding.
>
> I'd be happy with that. Presumably downstream can then patch
> things so qemu-kvm-compat defaults in the way they want (if
> we don't like the configure option).
>
> However, that's not compatible with using PC_COMPAT as far as I
> know (unless there is some cunning way you can make a machine
> parameter change compat_props things).

Monkey-patching MACHINE_GET_CLASS(machine)->compat_props?  Gross, but I
don't have better ideas to offer.