On 14/02/19 17:21, Markus Armbruster wrote:
> * As an interim step, the #DeviceState:realized property can also be
> * set with qdev_init_nofail().
> * In the future, devices will propagate this state change to their children
> * and along busses they expose.
>
> This sentence is five years old. Any progress? If not, any intentions
> to make progress?
Good news, it's done! What we still don't do is removing
qdev_init_nofail and realizing the whole machine in one fell swoop.
Bad news, it's been done for five years:
commit 5c21ce77d7e5643089ceec556c0408445d017f32
Author: Bandan Das <b...@redhat.com>
Date: Wed Mar 12 21:02:12 2014 +0100
qdev: Realize buses on device realization
Integrate (un)realization of child buses with
realization/unrealization
of the device hosting them. Code in device_unparent() is reordered
for unrealization of buses to work as part of device unrealization.
That way no changes need to be made to bus instantiation.
Signed-off-by: Bandan Das <b...@redhat.com>
Signed-off-by: Andreas Färber <afaer...@suse.de>
so I don't expect that the next step will ever happen...
> * The point in time will be deferred to machine creation, so that values
> * set in @realize will not be introspectable beforehand. Therefore devices
> * must not create children during @realize; they should initialize them via
> * object_initialize() in their own #TypeInfo.instance_init and forward the
> * realization events appropriately.
>
> This is mostly greek to me. Pity the developer who knows less about
> qdev than I do.
The first part refers to what virtio_instance_init_common does:
object_initialize(vdev, vdev_size, vdev_name);
object_property_add_child(proxy_obj, "virtio-backend", OBJECT(vdev),
NULL);
object_unref(OBJECT(vdev));
The second part doesn't apply to virtio because it has a bus (so the
code from the above commit handles recursive realization automatically).
hw/sd/milkymist-memcard.c has an example of this:
object_property_set_bool(OBJECT(carddev), true, "realized", &err);
but it should create the device in milkymist_memcard_init rather than
milkymist_memcard_realize, in order to obey the directives of the sacred
book of QEMU.
Paolo
