Re: [Qemu-devel] What's the next QEMU version after 2.9 ? (or: when is a good point in time to get rid of old interfaces)

[Gerd Hoffmann]

  Hi,

> > Just like -device is a general way to plug in devices, replacing
> > multiple special ways (-net, -drive, -usb, ...), we could use a general
> > way to configure onboard devices.
> 
> I looked at the -device implementation to see if the bus= parameter
> could be used to specify onboard device addresses, but I think you may
> be right that we need a separate command-line argument for onboard
> devices.

I think so.

There is -global, which is actually used by libvirt to configure
built-in floppy devices.  But as the name suggests it sets properties
globally, i.e. for all instances.  Which works in this specific use
case, as there can be only one floppy controller per machine, but I
don't think this is something we want build on.

There is -set, but that works only for devices created via -device,
because it operates on QemuOpts, and we don't have QemuOpts for built-in
devices.

We probably want something like
  -qom-set-property {objpath|alias}.prop=value

cheers,
  Gerd