Re: [PATCH v12 4/8] iommu/vt-d: Add bind guest PASID support

From: Jacob Pan
Date: Wed Apr 29 2020 - 18:24:04 EST


On Wed, 29 Apr 2020 16:12:01 +0200
Auger Eric <eric.auger@xxxxxxxxxx> wrote:

> >> in last review Eric raised the open about what about binding the
> >> same PASID to the same pdev multiple times. We discussed that
> >> should be disallowed. Here can you check whether aux_domain is
> >> enabled on pdev to restrict multiple-binding only for
> >> sub-devices?
> > Why aux_domain is sufficient? A pdev could have aux_domain enabled
> > but still bind pdev many times more than its mdevs.
> >
> > Either we allow multiple bind or not.
>
> I tried to figure out whether binding the same PASID to the same pdev
> was meaningful. I understood it is not. If this case can be detected
> at VFIO level I am fine as well.
I will remove the multiple bind support for now. Reintroduce it when we
enable mdev.

Thanks,

Jacob