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Date:   Fri, 13 Jan 2023 11:33:49 -0400
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc:     linux-kernel@vger.kernel.org, iommu@lists.linux.dev,
        joro@8bytes.org, robin.murphy@arm.com, ashish.kalra@amd.com,
        thomas.lendacky@amd.com, vasant.hegde@amd.com, jon.grimm@amd.com
Subject: Re: [PATCH 1/4] iommu/amd: Introduce Protection-domain flag VFIO
Message-ID: <Y8F53dzdebKLTlOy@ziepe.ca>
References: <20230110143137.54517-1-suravee.suthikulpanit@amd.com>
 <20230110143137.54517-2-suravee.suthikulpanit@amd.com>
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On Tue, Jan 10, 2023 at 08:31:34AM -0600, Suravee Suthikulpanit wrote:
> Currently, to detect if a domain is enabled with VFIO support, the driver
> checks if the domain has devices attached and check if the domain type is
> IOMMU_DOMAIN_UNMANAGED.

NAK

If you need weird HW specific stuff like this then please implement it
properly in iommufd, not try and randomly guess what things need from
the domain type.

All this confidential computing stuff needs a comprehensive solution,
not some piecemeal mess. How can you even use a CC guest with VFIO in
the upstream kernel? Hmm?

Jason