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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?t68Cu5GgXjWdbvw03SEw9f1a9kzapp2NLNk4TPnDHN7dzeyhJIgCE2/k29ZI?= =?us-ascii?Q?KnNFCM4PkJfSchwgUdXAwprd64leMtGLD9TwJb+Xdl4iV0wd6GuZVjYREl9m?= =?us-ascii?Q?xf7XOnUe36fojAkH+U653SyPoNn/XKJ2tJhQDDqnTYyN2MRn9Gg9Gd2D9wyT?= =?us-ascii?Q?7dOKIQZ5YZpjoQyQCOfu1uOmbfJDqE3fj44Zau17NSMVgtajUpFcolYUjkk5?= =?us-ascii?Q?IUAXF5FthjG6W1iwWCjT6dKs605LcIt6e7vN4mxauukrCOD3WU6kGKkpest1?= =?us-ascii?Q?luCDhYd+2ba7qLKhMMHKka/PAtcCU/9fsj7Ty6XwtDEuPn51L9881PxIV7Tz?= =?us-ascii?Q?PDwAjx01ImhsxweL2R2dG3eQjzblPtUA2w++AFJMhSIhEGRtjY7bhHmPVvcp?= =?us-ascii?Q?HEKn+hCk/vIxOg54JO3VXEAHPZ5Nu8YwAy1e78RujpvtH3wEJpbfyHoSa6Rx?= =?us-ascii?Q?pij4m3PqJbRGNshcOKcZKjUOOnvFDViP0clzNPhwXCAhNsXYO882UeOisY0R?= =?us-ascii?Q?BLtP0jaBNJUntq0Xz9WuYyTWl+yLEypgNnNPlYCPP3wAynk9NenwTIwSTsut?= =?us-ascii?Q?auH06C+74q5kpTLOhgbtF4qQex9ysTii+tz/FmJyT7K1Vwyp0+JktqvE8IZ0?= =?us-ascii?Q?NAc5UrpmRe4A+9lUE94E0E2VKEWvAnCeEsTsL+0VN6FfM5Au9xe/dkKHo463?= =?us-ascii?Q?A/YLbFcKgbI78aVbNbwBmDQWPDKbiAOAT9QwI+bViU6OglOANYhzqOuSntg6?= =?us-ascii?Q?TB59XkQ5IQtostTRkBGdIRLbXCV2YrBMhTybaaaMFyxdkE0NKVYcV+9pIajv?= =?us-ascii?Q?Ox7mcl8BDZPkspM2qbAAiWHmsZUp25TjPzlptGiFNVLB5BZ0Qzq4qi/USJV9?= =?us-ascii?Q?Nqr2u8BzTaeORWqcAos7T6xFd30X5ullNIvGiGeKOZSyL86phlN9UfvN2xAO?= =?us-ascii?Q?20si3zmDt7CPUu3wRa2x1tXEKb+BPNgF+DeJIIS8zsXw5KQjWQ839TcquKVQ?= =?us-ascii?Q?JEXgR2WyyloNzvd/SvFVJ8HOaTK3AzBYVh9BrM9QEB08hy2GFAS78apVflSS?= =?us-ascii?Q?fSfSBOVnK0/LpsBa14mcfztK6XoLn4FePMa/5C0M1wuwlhRfDKoWq1kCOE/2?= =?us-ascii?Q?+zUGIjoZx+PQLB7bukYvU2yh7xpBHQnIcIS6uAlorMEfQ8cHhAog/6ECVdbV?= =?us-ascii?Q?tzlMVIn63p7n9oPEamZ+XkQi17EDB7t+qATj75OxifKtKHBNIEZFpRovgpPl?= =?us-ascii?Q?AIHSfkH/exCOJwpnlnoYG3CJOlQyah+ssXEd0/MlthMFqum0pBUVGNlF47FA?= =?us-ascii?Q?s4SYh7OUCGCvqvHDKooo2wUF6u0kVD4sqXVn1IX1rM0Rnn0m3vDajqFam0+j?= =?us-ascii?Q?/NvQs4IK6sh6G7fAG777PdRATxGcHLp0ITZW/EOaHESUqnP81lucAf6Ijhxb?= =?us-ascii?Q?LWUIkTCouW16NXLfnQXZoDA51ITkcflavbnCmr+spA/tvcIXFq/cM7YDxZDk?= =?us-ascii?Q?mUQVD/9Kduv0BP0hkLKAAFC/qtXDwvCKIcuURrdNeoLdAIDW82QsN43ErHzJ?= =?us-ascii?Q?J7TUs3kx50H+iFxreh8LRv1HXu4lD3p29U3cSPFmNaxBS0wZrsAn5YuaIWkc?= =?us-ascii?Q?cNEyLkiN6MtSDHhBYc29zuQB9LkZ9+JW48lpQON4okZo5HFODlNhkuZZoMne?= =?us-ascii?Q?fs/Y8HM7HW2TqOtF9HZs0wu7NCPola3yE6BJVPVi1tRnxIWI?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: da0fdac0-7ec4-40ae-ddb9-08df2c910b39 X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Oct 2026 20:55:58.0978 (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: bDspOVmu8mKIPzpehbkSCmZG54ozFJOyOIB8i0bjNWa5BObanA9BpP/XcfGifYQG X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB8318 On Sat, Oct 17, 2026 at 10:06:04PM +0300, Jarkko Sakkinen wrote: > On Sat, Oct 17, 2026 at 11:16:07AM -0700, Dionna Glaze wrote: > > +Jarkko > > The TPM driver is pretty entrenched and heavily used by different user > > space applications, so it seems really ambitious to bundle in TPM > > here. > > This is something on the table thanks to Trenchboot and its early boot > code. I've proposed that there be no early TPM in the Linux DRTM implementation. The trampoline would just do a bit of additional work with its existing TPM code before it reaches Linux. https://lore.kernel.org/all/20261016165135.GA494690@nvidia.com/ My intention with attestation subsystem: tpm and DRTM is to follow the ARM design and get ACPI up enough to reach a HW driver. Attestation subsystem will multiplex the DRTM "PCR" logging to which ever ROT that DRTM launch selected. This is another reason why I dont like early TPM because it turns from just early TPM, already hard, into early-every-ROT which is much worse. I view all the stuff you are listing to make tpm early work as too difficult compared to just having the trampoline do it since it already must have a TPM extend operation inside it. Jason