[libvirt-users] Device lease hot unplug and events

[Milan Zamazal]

Peter Krempa <pkrempa at redhat.com> writes:

> On Fri, Oct 12, 2018 at 19:33:54 +0200, Milan Zamazal wrote:
>> Hi, when working on hot unplugs of various devices, I've found out that
>> hot unplugging <lease> device doesn't generate
>> VIR_DOMAIN_EVENT_ID_DEVICE_REMOVED event.  <lease> also doesn't have an
>> alias, so it wouldn't be identifiable in the corresponding callback.
>> 
>> Is this difference from other hotpluggable devices intentional?  If yes,
>
> Well a "lease" is not a device per-se. It's just libvirt putting it with
> devices. Currently the "lease" is always successfully removed/unplugged
> if the API returns success as there is no cooperation with qemu
> necessary so the semantics of asking the guest OS to do something don't
> apply.

I see, thank you for explanation.  Can we rely on the fact that lease
removal is and remains synchronous or is it a property that can change
in the future?

>> is there any better way of checking that <lease> removal is completed
>> than querying and examining the domain XML?  From user's point of view,
>> it would be best if I could simply handle the device removal event the
>> same way as with other devices.
>
> Yes, we probably should add the event and synthetize it for "lease"
> since we will not get one from qemu. Also we'll need to add alias for
> the lease so that the event can be used.

Since this is what an uninformed user expects (and I believe libvirt
documentation doesn't contradict), I'd like to have the event + alias.
Should I file a corresponding bug or RFE?

Thanks,
Milan