From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Gunthorpe <jgg-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
Subject: Re: [RFC PATCH 15/18] cgroup: Introduce ioasids controller
Date: Thu, 4 Mar 2021 15:02:53 -0400
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To: Jacob Pan <jacob.jun.pan-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
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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