Re: [Qemu-devel] [PATCH v3 5/6] iothread: add "iothread" qdev property type

[Stefan Hajnoczi]

On Fri, Feb 21, 2014 at 2:01 PM, Paolo Bonzini <address@hidden> wrote:
> Il 21/02/2014 13:45, Stefan Hajnoczi ha scritto:
>>>> The rng device examples don't seem to help because there is no way to
>>>> specify the rng backend via a qdev property (we always create a default
>>>> backend).  I need to be able to specify the object via a qdev property
>>>> to the virtio-blk-pci device.
>>>
>>>
>>>
>>> You can do that, see virtio-rng-pci.  It creates a link and forwards that
>>> to
>>> virtio-rng.
>>
>>
>> No, virtio-rng-pci has no rng qdev property.  The user cannot set it
>> on the command-line:
>
>
> Sure, it has no *qdev* property, but lo and behold:
>
>     qemu-system-x86_64 \
>         -object rng-random,filename=/dev/random,id=rng0 \
>         -device virtio-rng-pci,rng=rng0
>
> This is why I believe we want static properties in QOM by the way, not just
> in qdev.  So that this rng property can be documented and not just magic.

Hrmm...so the command-line is already populating QOM properties and
not qdev properties.  Then adding DEFINE_PROP_LINK() isn't really
necessary.

Stefan