Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org> wrote on 02/16/2016 01:00:28 PM:

>
> On Tue, Feb 16, 2016 at 11:44:06AM -0500, Stefan Berger wrote:
>
> >    Scratch that. The easier way to fix this was to release the tpm_chip
> >    after the vtpm_dev.
>
> Right, that is nicer
>
> Did you solve the lock ups when register fails?

The re-ordering of the tpm_chip and vtpm_dev release actually solved that problem.

[My feeling is, something outside of the vtpm driver doesn't unroll properly and locks up if there's lots of concurrency].

>
> One other thing you can look at is ditching the vtpm struct
> device. With the last patches I sent the tpm core would only need two
> more lines to work with a null parent device, which would be even
> simpler for vtpm.

Not having a parent device isn't really necessary, except for not having it appear in sysfs maybe?

   Stefan

>
> Jason
>