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Peter Anvin" , Sean Christopherson , Paolo Bonzini , Andy Lutomirski , Peter Zijlstra , Bjorn Helgaas , Marek Szyprowski , Andrew Morton , Catalin Marinas , Michael Ellerman , Mike Rapoport , Tom Lendacky , Ard Biesheuvel , Neeraj Upadhyay , Ashish Kalra , Stefano Garzarella , Melody Wang , Seongman Lee , Joerg Roedel , Nikunj A Dadhania , Michael Roth , Suravee Suthikulpanit , Andi Kleen , Kuppuswamy Sathyanarayanan , Tony Luck , David Woodhouse , Greg Kroah-Hartman , Denis Efremov , Geliang Tang , Piotr Gregor , "Michael S. Tsirkin" , Alex Williamson , Arnd Bergmann , Jesse Barnes , Jacob Pan , Yinghai Lu , Kevin Brodsky , Jonathan Cameron , "Aneesh Kumar K.V (Arm)" , Xu Yilun , Herbert Xu , Kim Phillips , Konrad Rzeszutek Wilk , Stefano Stabellini , Claire Chang , linux-coco@lists.linux.dev, iommu@lists.linux.dev References: <20260225053806.3311234-1-aik@amd.com> <20260225053806.3311234-5-aik@amd.com> <699f238873ae7_1cc5100b6@dwillia2-mobl4.notmuch> <04b06a53-769c-44f1-a157-34591b9f8439@arm.com> <699f621daab02_2f4a1008f@dwillia2-mobl4.notmuch> <20260228002808.GO44359@ziepe.ca> <69a622e92cccf_6423c10092@dwillia2-mobl4.notmuch> <20260303001911.GA964116@ziepe.ca> <20260303124306.GA1002356@nvidia.com> From: Alexey Kardashevskiy Content-Language: en-US In-Reply-To: <20260303124306.GA1002356@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SY6PR01CA0079.ausprd01.prod.outlook.com (2603:10c6:10:110::12) To CH3PR12MB9194.namprd12.prod.outlook.com (2603:10b6:610:19f::7) Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH3PR12MB9194:EE_|MN2PR12MB4079:EE_ X-MS-Office365-Filtering-Correlation-Id: f9b1eb29-628c-43c0-583b-08de79b9b251 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|1800799024|366016; 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Right. The assumption is that if the guest wants finer control - there is secure vIOMMU (in the works). > I suspect AMD needs to use their vTOM feature to allow shared memory > to remain available to TDISP RUN with a high/low address split. I could probably do something about it bit I wonder what is the real live use case which requires leaking SME mask, have a live example which I could try recreating? > Alexey, did I capture this properly? Yes, with the correction about sDTE above. Thanks, > > Jason -- Alexey