[Qemu-devel] [PATCH 0/4] qdev realize, -object, and -object-late

[Anthony Liguori]

As part of implementing the virtio-rng backend support, I decided it was best
to split off the generic part of the series to make review easier.

This series does a few things.  It adds a realized property to DeviceState.
It does so in the least invasive way possible and I think this is the right way
to break the log jam here.

It also introduced two new command line options which are basically the same:
-object and -object-late.  These options are like -device but let you create
arbitrary QOM objects.  -device is now equivalent to -object with a little bit
of additional magic to do bus resolution.

Instead of:

 -device virtio-rng-pci,rng=rng0

You can do:

 -late-object virtio-rng-pci,parent_bus=pci.0,rng=rng0,id=dev0

The reason for having both -object and -late-object is that late-object is made
after machine init whereas -object is made before machine init.  As soon as
machine init becomes a fully QOM mechanism, the distinction between these two
commands will disappear.