Re: [RFC PATCH 15/18] cgroup: Introduce ioasids controller

Jason Gunthorpe
2021-03-04T01:08:55Z

On Wed, Mar 03, 2021 at 04:02:05PM -0800, Jacob Pan wrote:
> > The interface definitely can be reused. But IOASID has a different
> > behavior in terms of migration and ownership checking. I guess SEV key
> > IDs are not tied to a process whereas IOASIDs are. Perhaps this can be
> > solved by adding
> > + .can_attach = ioasids_can_attach,
> > + .cancel_attach = ioasids_cancel_attach,
> > Let me give it a try and come back.
> >
> While I am trying to fit the IOASIDs cgroup in to the misc cgroup proposal.
> I'd like to have a direction check on whether this idea of using cgroup for
> IOASID/PASID resource management is viable.
>
> Alex/Jason/Jean and everyone, your feedback is much appreciated.

IMHO I can't think of anything else to enforce some limit on a HW
scarce resource that unpriv userspace can consume.

Jason