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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. 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?EbT4DmbqLSu3wfxyF6buvKo0xGMC1w21XG8rTZGfVq+n4971pBv7/ADfmhhl?= =?us-ascii?Q?4bEP6V5VcTzJsDKSaS/5wRx8xX0/4akWuWPd6JwcpPkIlH4vA5De8S3C06hm?= =?us-ascii?Q?5SmM+xASDSAi1jJ2zR/0vjhUqK+oon7zESQsd/hMq07j+4WKcHutV5F51d4Y?= =?us-ascii?Q?fb4H8uQOJnyRwYMvWfgD3q2RzXMtgsw6Re8i+ACbKcKklZ6Fvg6ipetXclfX?= =?us-ascii?Q?rrNI6suivRTKO/g9ABT3O3XYiSSJuwwuVA6yIiP21PafddQPQB3ykqu7KRa3?= =?us-ascii?Q?d/0g/0yJNj5uQwjO0uzZwLJsGV0Bf9k8r0bUwy2F/T3XyabxAUqzsXEJr+Sc?= =?us-ascii?Q?7TocTjDUm+XCFK7gaQ9ArZtVCIxP3386cY3Js2IfMuZDmr7S7MlBK3sFNdFE?= =?us-ascii?Q?oN6vK9SUfIDUgK0NeLw+RI4QGlqqtR+rzlTgJyEzlExcp97fxBLhjUbOddr8?= =?us-ascii?Q?rJsLzcWtplRwsM3f/PGQQqStG3gCUaKHuWwh+Ko+IBOh2UVNfnQHc5NDyweo?= =?us-ascii?Q?FWJal7LPASkLaIAaXofFNIPOnpd4vxKJ+V6WsnQHzft6t967GhjWo7yVECFX?= =?us-ascii?Q?sS6ZcjRCpqGBhzapHtCS+8hwrqB1in16KnfBLSG39UBf5JGygBHFtPhpOd0m?= =?us-ascii?Q?rGcjWNsh2OhE30T2FJca5GvD0LLNCxrQng2WPczAp5npIHVxQ1fEu6XfLmlo?= =?us-ascii?Q?hqQ3JJxPOK8rxcg03CI7KsT/nssWYzLmCU1lju6SUbwGBuMY6i1X2s9uooEA?= =?us-ascii?Q?3n867H25RNYNRwM6R/iBcvV2sGywL+PT2FNrOBKszqzM3H3sw3d93Li+ECwt?= =?us-ascii?Q?Is1T0CA3KQ7H5zCjRrqm/2/Q9N77PkqzKrJPkDQsNLBfFXw2DVeAmvBuHCiZ?= =?us-ascii?Q?ONYmT6YsZ6fGx+cIt9yUAyHoX5T1h/OJSeDukYchY/4RLjtnBTY5RBoHb6Bn?= =?us-ascii?Q?erzrvTW4AzmqX9VGM53RvVEkW7j3k5hGMOb9eEy0WxUZTlWv4AjecD4sIvhU?= =?us-ascii?Q?qbAWu845oVN25w+Yuvp64rMpsT7c5ZBDhFbu+wtdm8mBJ41mPcoA7XfOhsKt?= =?us-ascii?Q?G//vdUriaMixQ/dyQ8NKOoNpS3/Uty/9BRZjrlPoaerJ1IH93ICDVTaY49Fv?= =?us-ascii?Q?BA25WHlQnpoTROy/YUlKOg7MXoD+8n7gnKMaRrAxtpHRa7gsm35b42eDZA6O?= =?us-ascii?Q?MoMS9HO0xARQHhSeuCXbu8ciTBVYCKh9E5ox2X+BgKTgpbcLSSxgv2c1dtyb?= =?us-ascii?Q?6QeWIV6ZMUk+1hE+m+YTSCULCbS0nFAvL9AEBDt7GJlpENPII6oZru3dBlHz?= =?us-ascii?Q?ApwWDaoZ2Bth17M77oNvEs18VWYNTiky/tvMLyVcNX2qfTB8Hn9MqOPNLSIX?= =?us-ascii?Q?7nsRSt+T2EZEiY6WQDJXCG98xhYC7HRBal4S2TikYWZ/LSs9ivk5wUoKOgCu?= =?us-ascii?Q?ejqx7ag2BI4aAUFOAbHUfTmPdEsy6PxQ3RTod7ReuEq/8laecmIzO3iNlczz?= =?us-ascii?Q?61a/j3NY//0o8PTTPmwpNFRB36u14jsU0gkOb8qAYQVGR4JmWWWSU4Ty0csz?= =?us-ascii?Q?emhMToVJuOjrytnt3W96P9w6xEtXvO43k0av935K+w3013PU1CIg+V3Oe2Zg?= =?us-ascii?Q?F+LMENWjIGjPwhNkjJWR/a/wyRhsTMRAiq6PzX0bHZhx/6nGMefwfq1wRlTr?= =?us-ascii?Q?TkqO1MFAhq45B/+eCp53GM5nEFOzkE6I89pOUsbRKvAvftoH?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3dd0ea43-4dfb-4e77-16ae-08de9f37a5d4 X-MS-Exchange-CrossTenant-AuthSource: CY1PR12MB9601.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Apr 2026 23:50:49.2522 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 7obP3l/Klnfog07902aRxR+yQfj4H6Fg8JVwFz4AmTla8CZVaC/fW/FjCNTg0jMv X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7890 On Wed, Apr 15, 2026 at 04:32:14PM +1000, Alexey Kardashevskiy wrote: > > > So the DMA API should see the DMA_ATTR_CC_DECRYPTED and setup the > > > correct dma_dddr_t either by choosing the shared alias for the TDISP > > > device's vTOM, or setting the C bit in a vIOMMU S1. > > > > Something like that? > > > > https://github.com/AMDESE/linux-kvm/commit/266a41a1ea746557eb63debce886ce2c98820667 > > > > With some little hacks I can make this tree do TDISP DMA to private or shared (swiotlb) memory by steering via this vTOM thing. 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? Jason