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From:   "Tian, Kevin" <kevin.tian@intel.com>
To:     Jacob Pan <jacob.jun.pan@linux.intel.com>
CC:     "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>,
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        Lu Baolu <baolu.lu@linux.intel.com>,
        Jonathan Cameron <jic23@kernel.org>,
        Eric Auger <eric.auger@redhat.com>
Subject: RE: [PATCH v7 09/11] iommu/vt-d: Add bind guest PASID support
Thread-Topic: [PATCH v7 09/11] iommu/vt-d: Add bind guest PASID support
Thread-Index: AQHViqRYHs7rkU/ej0S5OBwc0DBZHqdq78JwgAApg4CABHtLgIAAIj+AgAGQXhA=
Date:   Tue, 29 Oct 2019 07:57:21 +0000
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> From: Jacob Pan [mailto:jacob.jun.pan@linux.intel.com]
> Sent: Tuesday, October 29, 2019 12:03 AM
> 
> On Mon, 28 Oct 2019 06:03:36 +0000
> "Tian, Kevin" <kevin.tian@intel.com> 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