Re: [PATCH 06/12] vfio/ap_ops: Convert to use vfio_register_group_dev()

Tony Krowiak
2021-05-04T13:58:58Z

On 5/3/21 4:33 PM, Jason Gunthorpe wrote:
> On Mon, May 03, 2021 at 04:14:43PM -0400, Tony Krowiak wrote:
>
>> This case will occur whenever a user removes the mdev
>> by echoing a '1' into the mdev's sysfs 'remove' attribute
>> file. I'm not sure it can be considered graceful to take away
>> all of the crypto devices from a guest while it is running,
>> but there is a way to process the remove callback without
>> leaving things in a "weird, half-dead state".
> It is acceptable to just sleep here until whatever user controlled
> condition is resolved.
>
> Jason

I suppose we could do that, but the user that tried to remove
the mdev via its sysfs 'remove' attribute will be left sitting
there wondering why the operation didn't complete. That
could result in leaving the user hanging in perpetuity.

IMHO, the callback should continue to return an int and
the caller should display the error if a non-zero rc is
returned.