RE: [PATCH v7 09/11] iommu/vt-d: Add bind guest PASID support

From: Tian, Kevin
Date: Tue Oct 29 2019 - 03:57:25 EST


> From: Jacob Pan [mailto:jacob.jun.pan@xxxxxxxxxxxxxxx]
> Sent: Tuesday, October 29, 2019 12:03 AM
>
> On Mon, 28 Oct 2019 06:03:36 +0000
> "Tian, Kevin" <kevin.tian@xxxxxxxxx> wrote:
>
> > > > > + .sva_bind_gpasid = intel_svm_bind_gpasid,
> > > > > + .sva_unbind_gpasid = intel_svm_unbind_gpasid,
> > > > > +#endif
> > > >
> > > > again, pure PASID management logic should be separated from SVM.
> > > >
> > > I am not following, these two functions are SVM functionality, not
> > > pure PASID management which is already separated in ioasid.c
> >
> > I should say pure "scalable mode" logic. Above callbacks are not
> > related to host SVM per se. They are serving gpasid requests from
> > guest side, thus part of generic scalable mode capability.
> Got your point, but we are sharing data structures with host SVM, it is
> very difficult and inefficient to separate the two.

I don't think difficulty is the reason against such direction. We need
do things right. :-) I'm fine with putting it in a TODO list, but at least
need the right information in the 1st place to tell that current way
is just a short-term approach, and we should revisit later.

thanks
Kevin