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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. 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?gcftIQnGC1Qk7HSfMuJaPdpl/vPhK110unKsXA6fxh1/Nn6nL2drXEl05Zfi?= =?us-ascii?Q?v+TdSGSUgZOXkcxG4As5oPHpCrxrXnqh6Xyb93xhNLf1N//oiAXx0kYxXoUZ?= =?us-ascii?Q?Ch4bvijvSJniXyj2o3XR4j4X55IaY09ZnabrowGWphlW7VYP51wE0zp6DH0G?= =?us-ascii?Q?BqOh8k1tMP3eWr5VYzXU5RS4Y91l+7OtIpOJfwdVFyixLusamsdLYMm/0qGm?= =?us-ascii?Q?4RRlilxUIaSyeTSQ3t+syMP/Ow23iLM+D5E6MsdLUoFLAD4veJO+BIXtec3T?= =?us-ascii?Q?NZ23YGkr0eyyXE37S3OM4RuQQ94vB7tYPu9ALtnM/4x7K2rTF6Brak6ihOap?= =?us-ascii?Q?QOJATM/Zh1GYyqwSedBp1xwdB85OmeGwtxqLTKniZIi8A/pC5qsdwCSSq4JW?= =?us-ascii?Q?FkoDDAs00C75rMWGmZNbhGC/Y2fLRFdtUxYcOGQg3U4rn9erfarh4EnjgNZc?= =?us-ascii?Q?xRIgzCmQnE6DbcPuAKB9RNlNHu6n1rts98yktjKBc1AcKHn0YkeknbQe0t+n?= =?us-ascii?Q?vgngXoCBEo6unyHHOcn2VqbbCWBRkWkjGPfNiGP4+hs5zFL61dDIYdNin431?= =?us-ascii?Q?0bdokx6t8pFaP0dsmoT1BcFYTMkjQATzvab2nOlzRkq/OVrX59SyJHsY8KRW?= =?us-ascii?Q?V4/qjLhf5kSpK8XSlPaYsvJPeseFFGqSUrLznRqa8j/7GCkmscJ6t2ETwtod?= =?us-ascii?Q?9iSTqG1zssjXTOwp3iZ7bXsIj5UQeu6wtHh5tJ9oIDUiZ6AXlLU/GPsCOrMX?= =?us-ascii?Q?5U+kPrjUWhgNsOLBSzQS+FETkAPCXvxHS4ZEqe4rFKd3vBBk3B0kSoWllFXr?= =?us-ascii?Q?vp4MJhoGHfd3dkmbvbuRka9rPq652to731rkshxUP+c3hostTlWIMIhOAPp6?= =?us-ascii?Q?Bl/jTg2sSDh6hgeg1DOhBc7vKYNUXVLzMIs3m3utpn9X7RRJk8GCkdLNCovO?= =?us-ascii?Q?FztKIcGXVgHrtaaKoR2cw82Wr8BgLgmvtvKyjOffFbotuFtU9W8aRZk1TO0X?= =?us-ascii?Q?eZ4LATBFjqy/2yRL6Uj5MBpLWzDDtV1rRfbrQdnxPUYxUPWLVPu8HTyW5inj?= =?us-ascii?Q?wVMuT3ANEKY9RtPKGlHXZmB4Dn//tV2+G2uMbJG1FpV34dL0fqdLqV+gNmRR?= =?us-ascii?Q?+CehZ4iaQJKgfzQrROLoI6RI/gf/hekrIYfmEf/hPUULwzp9S6i/N1lYEXmN?= =?us-ascii?Q?WDwYiVpHeBRbAJUWUKS0avhJpdOEw+g18gziYczdys/pnc/HfL69CFQnYYs0?= =?us-ascii?Q?rI3U/RvTv0rhpiEunGbHtnlmcCOfHfanz0HOQ6YUmeddKb2PgFhNZiQTQxom?= =?us-ascii?Q?ZefbEHNIy6ZqvH035WlHrI8S8zMZJ7CGxhVhInKBmUFuvcyDXUkRYxjurYTU?= =?us-ascii?Q?vA1+byQqD7+GyEFL2dMXjoJW8OaKF43uHDGAaIzekbNMtgPFWX0DQwPXEh3o?= =?us-ascii?Q?HQOPe3fBzvNDoG4c4mVIhwwtF/IzJko+IbLFNKOlZDdcVjXliwm4ySJW/T7a?= =?us-ascii?Q?aLlJDVNno3eHJ2Y0RMxi0KOnFxfEkH7gJKL5oaC0AiM6Oksju66twuG0aRHy?= =?us-ascii?Q?uWOtQQMhhgzzJHvTFLlq01/uWv05LPuaAqDB2rfpd1JJKCPg1AxeKrwDXB/G?= =?us-ascii?Q?Wo6Zm44b53/Spnh00YXPKgWYXfQL6xxSF6lebH0E0fzqRd8DDEtMR7MzmLFk?= =?us-ascii?Q?CpysKHO+tn1BvIcKJfSJ93UhL8I5A7smBNQL/Gvw1yDSOPB102mbu3Nwldqa?= =?us-ascii?Q?jRl7QJ5OGA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 69756e54-921a-4523-2c7b-08de79eb9c2f X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Mar 2026 12:43:18.0796 (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: EloZd/bHkCes+B0M546kdDs1Hrzk83EaIsudh2vrXR10lSBADR25ADOjQ+ct4WJy X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR12MB6222 On Wed, Mar 04, 2026 at 05:45:31PM +1100, Alexey Kardashevskiy wrote: > > 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? We need shared memory allocated through a DMABUF heap: https://lore.kernel.org/all/20260223095136.225277-1-jiri@resnulli.us/ To work with all PCI devices in the system, TDISP or not. Without this the ability for a TDISP device to ingest (encrypted) data requires all kinds of memcpy.. 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. Jason