Rorie, this is to inform listeners on the host of the guest.
The guest itself already sees this "inside" with uevents triggered
by the AP bus code.
Do you have a consumer for these events?
There is a series of QEMU patches that register a notification handler
for this
event. When that handler gets called, it generates and queues a CRW to
the guest
indicating there is event information pending which will cause the AP
bus driver
to get notified of the AP configuration change via its ap_bus_cfg_chg
notifier call.
The QEMU series can be seen at:
https://lore.kernel.org/qemu-devel/7171c479-5cb4-4748-ba37-da4cf2fac35b@xxxxxxxxxxxxx/T/
Kind regards,
A Krowiak
