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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?vxNhOBqwCEI0TG3JqOQQjxW/oRPMh6JDFbEIPJOcRfWiWtR6NjmzwU92h4z7?= =?us-ascii?Q?S1p1GaLoMuBHIk3NwaAkbN9NamexaX2gFJ+YrQ1F6xxvFLVjM+G1UO3emFUp?= =?us-ascii?Q?1niA/Ks4FClXXDBlQAHxUZZoaCpJ/OLyq+aiWXt2LLoIm4DikVWrXGE65C0v?= =?us-ascii?Q?pH/yZIvRn87eirdCNLxC+VLWWmrJAGGmkpC4X+mekoSfcpXG//cGtFWhb6KO?= =?us-ascii?Q?RmrHuBQZ6CIdlrDwYlqp9hIN9U0M5oRBWwGAX2kcFIqsJJop0bThm0CHn1iu?= =?us-ascii?Q?pDup4nfVEXniHsEZt0WT82SWL3vgGjvX8jPQY1gaxY1Xei03jU/K92+jEPGk?= =?us-ascii?Q?O91rmqr7coSQPXs/OwkveSuP+UqEEjO7K/FbncOmBISokKAMVO74qlhG5BRX?= =?us-ascii?Q?MBgMiKVemfgt15A1cNGxppuhvZ27ukLR3LRxnKb/9J18OPsX7FXENBkbViP/?= =?us-ascii?Q?qNXLE0KuTOZkQyCy/b0m6xFSTlzIYOzt5o0Hdck7guJFmJz3CJn2QWngxVGG?= =?us-ascii?Q?TAnLtZiIMYyUl7CW+y3uYtVwoR/yYvJfvod++FzlS5R6ATWHwfWE3EHOsKaP?= =?us-ascii?Q?S2tAGVZuue5D17lVPwo/Se8mWkAmVa1pqi+zHkC0vG8WKY2FCx5hovY0cwar?= =?us-ascii?Q?MC8GeozC3wUbCL3vL8Dfq53wqSufQDOsJuLlK0W+BoZtgXQYP+0A+sAu0iT5?= =?us-ascii?Q?7d6JnnLDCAnZ205aCuvGAMP8XhwA1tpNwKsNjPcPov7chHgvhhdXpHnvU6OX?= =?us-ascii?Q?JsFQC9KdjeMR1BbTfjhECo9f4IdDnfQjY4ISmyRakvpBrNc16VSHTGmXgC9F?= =?us-ascii?Q?r4roiRjkN+tjz3TNwDaKnnAMC8ivSSsEyNUV69eztiKblMAU1UKuPcjiY7et?= =?us-ascii?Q?XCP3QRLyF5/7RAxN5snua5ytLqVMxPhO9G0WJWBhoIQQ0s6LGn9CVDNIrvfA?= =?us-ascii?Q?SjPjQKU2xY7xvHSgrMQg09/2R/FOMV6vaYQNDmmFlQaqZVcbg5Sx2NDBcEK4?= =?us-ascii?Q?rlq6l5vKlY0k0Nq1km5VNnhyFeQYtTRgb0Xn8nSLUJxGH3PBmR8OBzccKuC7?= =?us-ascii?Q?bf65h5axP21Orjzhy1lXwQwFY8/tUgWW/BJ/fJnE/1zZkGR90h1kCH+4Jgj/?= =?us-ascii?Q?HmQBK8YvGfXIaF/vkeexA/pBCSrlpDEpASEsdYnkC/0SVl4LR1JJPhe5ehas?= =?us-ascii?Q?1dgVRkIY2Sk9vg+k2lcK3VomMnYqADQ7c0zBLLp2ipPXg9ogj9bgJk5Yfpxf?= =?us-ascii?Q?e80CX2f/SIy42KZADzFwK+ShjLr1irNpcFpWoYLDTfH27AIOsWvJzfNFFTNn?= =?us-ascii?Q?d5RVqkaM6PA1NhJ18X/b59Ko5Ni1oAsGzsnInUzDtdXy5Q2VnVQWV+cXfgf+?= =?us-ascii?Q?tdduA15GGuGNdcTU8JaHTjrtnDxMWA7WyoD7W/iMhXWULY8Xd4EK1mS+Y6ED?= =?us-ascii?Q?ORxGCv5DFpcsLnoo9ls+TfvT3C68wgC9bbWCHlwj13u9u4VyxTudnk1Zt6YM?= =?us-ascii?Q?GNLVwRUjHQyt7RVB6e9qAHWzY0BdDUIvvVEeGvfsryYh3GhZPJFurEYIfW6y?= =?us-ascii?Q?Gt7sFnh9iD9qXjA2YJWnimKdfTOvow4lgKd8wczQvZfEHgZNShb7L27yJM1K?= =?us-ascii?Q?7lVephEYNK3FEc3v9Ba1zB7anQXYATCYwsXTTMnH79atVhccwNpn6GTjIPea?= =?us-ascii?Q?AInbR91rp9LuRYzioLhmQyShFHOmf7krOueCTZm121X6h75o?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a7ad60a5-c5f1-42ec-151c-08debfdb543b X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Jun 2026 12:43:06.6698 (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: UyDUnZwsx7DuhDj15fboGuZl3ANGCTzDnfM6CK/JOyqdfzE1t3njTCluteaxZIRf X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB6817 On Thu, May 28, 2026 at 05:17:15AM +0000, Suravee Suthikulpanit wrote: > The feature is advertised w/ EFR[VIOMMUSup]. Please see the AMD IOMMU > specification[1] for more detail. > > Introduce a new global variable amd_iommu_viommu, which is used to > control the feature enablement in the driver. Currently, the feature > is default to disabled. Once the feature is fully supported, it will be > changed to enabled by default along with a command-line option to disable > if needed. Still no to command line option. Just don't use iommufd if you don't want to use it. It must have no cost until iommufd activates it. Jason