On Tue, Dec 21, 2021 at 04:40:28PM +0100, Markus Armbruster wrote:
Paolo Bonzini <pbonzini@redhat.com> writes:
On 12/21/21 13:58, Markus Armbruster wrote:
Is this a regression? I suspect commit 5dacda5167 "vl: Enable JSON
syntax for -device" (v6.2.0).
Obviously not a regression: everything that used to work still works.
FWIW I think -set should be deprecated. I'm not aware of any
particularly useful use of it. There are a couple in the QEMU tests
(in vhost-user-test and in qemu-iotests 068), but in both cases the
code would be easier to follow without; patches can be dusted off if
desired.
-set has its uses, but they're kind of obscure. When you want to use
some canned configuration with slight modifications, then -readconfig
canned.cfg -set ... is nicer than editing a copy of canned.cfg.
Simliar: configure stuff not supported by libvirt:
<qemu:commandline>
<qemu:arg value='-set'/>
<qemu:arg value='device.video0.guestdebug=1'/>
</qemu:commandline>
There will always be a gap between qemu and libvirt, even if most of
them are temporary only (while developing a new feature). I think we
need some way to deal with this kind of tweaks when moving to QAPI-based
machine setup. Possibly not in qemu, maybe it's easier to add new
'<qemu:set device=... property=... value=...>' syntax to libvirt.
take care,
Gerd