On 12/15/20 7:13 PM, Cornelia Huck wrote:
I'm not sure how many rules actually care about events for the
subchannel device; the ccw device seems like the more helpful device to
watch out for.
I tend to agree, but the problem with vfio-ccw is that (currently) we
don't have a ccw device in the host, because we pass-through the
subchannel. When we interrogate the subchannel, we do learn if there
is a device and if, what is its devno. If I were to run a system with
vfio-ccw passthrough, I would want to passthrough the subchannel that
talks to the DASD (identified by devno) I need passed through to my
guest.
I think that can be solved by simply adding the devno as a variable to
the uevent (valid if it's an I/O subchannel; we don't register the
subchannel in the first place if dnv is not set.)
Providing the devno in the context of the udev event certainly helps if
the event consumer would base its actions on it.
As far as I understand the driver_override mechanics driverctl sets the
override based on a specified device. In that case the devno would not
be looked at and the subchannel would end up with a vfio-ccw driver even
so the ccw device might not be the one we want to use as pass-through
device.
--
Mit freundlichen Grüßen/Kind regards
Boris Fiuczynski
IBM Deutschland Research & Development GmbH
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