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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?FkiNN0Qt0KhzWfUjrf4htWppWl21njr6+vi51kA5znpkC6rFykdZ7NnLuQHn?= =?us-ascii?Q?2voAKskbUxZY0sr/wBihVSPobGCv4BFWTUKpm8eee7S1WF22w3mMNsjZshbK?= =?us-ascii?Q?ImZAv2ke7M1rOoVLHoXawDhGEzWztk63yAjkzFpe8C5jIU2QGi2faDoqa3un?= =?us-ascii?Q?AV/w0PZfmNVvQY4uT6o5RzoABYeNQiqAXSbtmyfBDEIOwlsvNxD8/cUPR5pJ?= =?us-ascii?Q?cXBfgu63WPMpo6XbPP+HlJwf1oVLj7nl4roWY5tja/DyssiZ8bsYbKsPAqga?= =?us-ascii?Q?oRJVAfDc99QmcF+E7oCVs//SJxlrrKIhYYD5DRmr1ELQ8YESkuRadyzj0MTW?= =?us-ascii?Q?8XIAON9vFxZvgz6v+8Audy3c/y6j8qHOKOmxr+wyaxII/CHF48jUR/Dn3ysr?= =?us-ascii?Q?DOYGboxG1b5+X/ZLuMuVkVSKxHDdO1KlLKt/JjesT5MUbNFf55nGE//GdXhp?= =?us-ascii?Q?g7SOfCiXfwVH8sAAOjgsNF277uALofi1EvakAjcN2kB5F/Q22EgKg1AXvkRW?= =?us-ascii?Q?OxKvwXiHJcfJKuF2zZabtdjiBV936CJHTazzjbDlWx/h6RjU8KZcHfRekEZ0?= =?us-ascii?Q?HqjuNXCV4mX2XwJbjLvBbaxQa7bM13tFYSjh5JFrIPh3xpUmf5BzfziaXHgk?= =?us-ascii?Q?DngHXTbzccOZ4APfKe/ySEtZgQSDxV9KoM5pjoinU1I5qVEeu+ltcZ4zlSlh?= =?us-ascii?Q?kFnm6B1zg5GyWcje0/0eyUrT1CC6j58gfm00Lik7pk8fvzwx7V7963P+ZWbz?= =?us-ascii?Q?NHXvO32yLGKDKh/LXg5t/17amQNtjURCRacQdu+9VPK/be4s3cWApl4aj3Ej?= =?us-ascii?Q?sz/5WMMHO73FjlrU3tb1tJu5PFMe0S7L0PPB/lRNWJhlUMaBxP60MIvY1Bve?= =?us-ascii?Q?N/iRzoTttfy3xLmKPedzYiNC16LtPeEwekycalCaxRiiyNI5UDq2BusMg2fZ?= =?us-ascii?Q?qPNG2hj+uZ2vOEtU4Hmlbs1zNI+d5/BFQ/icKBOonabvwf9m6hr6pwtYITTs?= =?us-ascii?Q?5WN1YLKpTd4DfWWnRaOpei6IMtM4jaA6063s2920uSzbOOd3Xgcwk9vMCfXh?= =?us-ascii?Q?uIa+n3b6a+EQM28FVqok/BFV0Y5L6hRjrpctHm2/bp9pYrRXsxb7rysD5X0x?= =?us-ascii?Q?2QVdsPnrUU4ajRQq774GzFQslbFlX6M2n1WhlfHMJZjK/GoA2RgGImBwT9QB?= =?us-ascii?Q?3mjjqpxzG7EkOT169uZ4ftp2teiIjQAA/cPDHmBFJ/Phh5p766wHBr4r8THR?= =?us-ascii?Q?zocaBY2ySEWK55AJW2F2MruTVSJQyaNzZZPOinN2f2XvztIL4qqeH4/d9xwk?= =?us-ascii?Q?ppyqKY4UbtXlGYwfqh+rhXqASyRPi80m+gZtlHGfakyJHT1egFPqa/gQUyqD?= =?us-ascii?Q?/Fo6rxkO0aKwCHM5A9iRLow3IDK5UA1zGceaTTwLnayXgjNOhSZkvY/vnGWn?= =?us-ascii?Q?1JkWkXBJ9tWrzStBfbFykgPoDtKtAJrIwjQ+UGNH7sML2ba2yyMvQnAMkbtO?= =?us-ascii?Q?3jQgYYKkS0MvutV0ApCAQTQJEHs8VDYZEH1OyHDMHAOO1JtC3Nn1wlr9lRuo?= =?us-ascii?Q?C0uagv0nmAG1JSP9WwTBBVxEDBUAzEMMgqxXqbYdPZc4BguGhA3eM5MPTvJe?= =?us-ascii?Q?ZGn04N0CV20rQ6KzHMlBQysDny795uehwgzzCTGT7ZvxjOqHWvGW2A1fzqlJ?= =?us-ascii?Q?A7Cul2nSzebueOrwqpVxp/xWmw0Awy0x2JoSfRI+GNLGyUKPCoX8SeaWuTLd?= =?us-ascii?Q?4RadQ/5vSw=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 195ddb5a-6c21-4739-d976-08de53a021b3 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Jan 2026 19:07:15.9834 (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: S7fCFJI/rS5KEEf2QBIZ4xnG/eWPMb1klmbeJqDLhe/4yY7ypaB6jSuGLjo3Xncm X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV2PR12MB5797 On Wed, Jan 14, 2026 at 10:51:02AM -0800, Samiullah Khawaja wrote: > There is no immediate use case for first level, as I understand we use > second level for all our VM use cases. But looking at the code and > specs, the first level is used for pasid compatible domains (using > IOMMU_HWPT_ALLOC_PASID flag) and it will not be replaceable > hitlessly.. If the VMM allocates using the NEST_PARENT flag it will always get a S2, and that is a reasonable thing for the VMM to do. Jason