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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 , 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: <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> <5d669086-a5c8-4e55-8108-a9fff41cf094@amd.com> <20260304124316.GL972761@nvidia.com> <074633eb-103a-4452-9aec-6cd61e82f0cb@amd.com> <137e5595-390e-49a7-8918-9ca057f7ebdd@amd.com> <20260420235046.GA3199414@nvidia.com> From: Alexey Kardashevskiy Content-Language: en-US In-Reply-To: <20260420235046.GA3199414@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SYCPR01CA0022.ausprd01.prod.outlook.com (2603:10c6:10:31::34) To CH3PR12MB9194.namprd12.prod.outlook.com (2603:10b6:610:19f::7) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH3PR12MB9194:EE_|DM3PR12MB9328:EE_ X-MS-Office365-Filtering-Correlation-Id: 70119e87-0799-4774-b53e-08dea66831c3 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|376014|7416014|1800799024|18002099003|22082099003|56012099003; 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Thanks, >> >> Ping? Thanks, > > That seems approx right, it is broadl similar to what ARM is > doing.. But the address map changes when switching to T=1 for AMD? Well, at the moment, in my WIP tree, I map the guest memory in the host IOMMU twice - 1) from 0 offset (and this is shared when T=0 and private when T=1) and 2) from vTOM offset (say, 1TB) - and this half of the mapping is always shared. Thanks, -- Alexey