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From:   "Tian, Kevin" <kevin.tian@intel.com>
To:     Jason Gunthorpe <jgg@nvidia.com>
CC:     Alex Williamson <alex.williamson@redhat.com>,
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Subject: RE: [RFC v2] /dev/iommu uAPI proposal
Thread-Topic: [RFC v2] /dev/iommu uAPI proposal
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Date:   Tue, 13 Jul 2021 23:20:12 +0000
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> From: Jason Gunthorpe <jgg@nvidia.com>
> Sent: Wednesday, July 14, 2021 7:03 AM
>=20
> On Tue, Jul 13, 2021 at 10:48:38PM +0000, Tian, Kevin wrote:
>=20
> > We can still bind to the parent with cookie, but with
> > iommu_register_ sw_device() IOMMU fd knows that this binding doesn't
> > need to establish any security context via IOMMU API.
>=20
> AFAIK there is no reason to involve the parent PCI or other device in
> SW mode. The iommufd doesn't need to be aware of anything there.
>=20

Yes. but does it makes sense to have an unified model in IOMMU fd
which always have a [struct device, cookie] with flags to indicate whether=
=20
the binding/attaching should be specially handled for sw mdev? Or
are you suggesting that lacking of struct device is actually the indicator
for such trick?

Thanks
Kevin