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

Jason Gunthorpe
2021-03-04T19:05:23Z

On Thu, Mar 04, 2021 at 11:01:44AM -0800, Jacob Pan wrote:

> > For something like qemu I'd expect to put the qemu process in a cgroup
> > with 1 PASID. Who cares what qemu uses the PASID for, or how it was
> > allocated?
>
> For vSVA, we will need one PASID per guest process. But that is up to the
> admin based on whether or how many SVA capable devices are directly
> assigned.

I hope the virtual IOMMU driver can communicate the PASID limit and
the cgroup machinery in the guest can know what the actual limit is.

I was thinking of a case where qemu is using a single PASID to setup
the guest kVA or similar

Jason