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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?uDK9a52uKMblSkwYUXIPZjt/hlSPXoMZtHygMogt0tbPnC9tK50QlkSsO9pL?= =?us-ascii?Q?3otJQVxKgcOSUsDoV+d8uOvCZD6bTk8xBC32YoKMj7y7GrE48xxYrh62Gygo?= =?us-ascii?Q?1spbIDaNDF/maSO7NWeiE9klnfgQKRbzvEoIsAR75ByUeKMgcgQX7gYs9HC1?= =?us-ascii?Q?/mAf6pRLoz5zzovX5W+xBOsXUbK0rXGaxiwxrSi8WEUfpffWVsQgW3TuQNdd?= =?us-ascii?Q?MG2TqToDHvydAq8lQAumAXPfSlQsQuKiz+hgdtlRGaYFZXuXSrnJasLg/SeP?= =?us-ascii?Q?oBxC6jrAHymvxWa3ZtBPCV/oWv1Q3p2pbmH1+/zvmbBz0kserObRWJy0vN4b?= =?us-ascii?Q?RMTeEbKNSnUVGvz7I3Mcc0Kejkj/oc9ZRAoMf66JGbD04ZBtgKFxGtqYUzOZ?= =?us-ascii?Q?ZTp2KdxSdmd6IjI/JKP/0rG3lsJFJaYfSwlkZAmO7SaAH457BUog8V+HrfoR?= =?us-ascii?Q?Zw0GgZXlBs3t5BQSZt1KkYGexqsM9xKD0wjiakrMAXNxPSKRcq3xaCJyKyhe?= =?us-ascii?Q?1P6Bk7r7CGc4Naj5Vb1Tw0d+L/WIce0xWiDvHiv5EezMf/QVx0kNsT2+kaew?= =?us-ascii?Q?5WWOHxgSxOFYNpPDCe4t2ERnCL+vvZ4D4SJeWel/MlAxyd1VpWKKlkH3841Z?= =?us-ascii?Q?0xcOgdjmMcuwVfoKDeHfxd8vxHBi51FYUCtEbAxqpBTo9NWJMw6y34njY4dR?= =?us-ascii?Q?dCamCjcw/pczaCq+ELIc5VajppISoyv724bMesOKikYsiVLyQLWgKT7fXrn2?= =?us-ascii?Q?kHsoT8F/bYDppjhfltB8jE3L1WsofZPrQMBeNkIQaxkKLROjwfMitBWYamBp?= =?us-ascii?Q?wB6zJ/IypZ/u835Xw/34gAExZnLgY8tPDHpAHSC+IK+6UF9HZ5ztQZTZBavz?= =?us-ascii?Q?F8m/cCUXJf0c5zS04kkbDSfUjAD//4yb4IbA0znleIgqvRvEZffL96IIe66o?= =?us-ascii?Q?ZznxmOl6qOWkScOUyRLhnd298xY992qT5Y562GmpEXRvJUavtYEXEOarEH18?= =?us-ascii?Q?QnST3Wk1u1W7Q7GlGF3eDek2wHiHjbccVdVnpKIDd25AHXbBemIOst6oHRMf?= =?us-ascii?Q?sjezaKRbK5kcZZP0tuFiBOZbMgdM2FutOL1SJIS0XhVeBEb6vuSrSI9KEFgr?= =?us-ascii?Q?fhVhFFNoTyPLD75oPqA68OQpXuH37P80IFhoi1683i5gxbeuMfUj9/UsAre5?= =?us-ascii?Q?vmBsFDO0bj9A3AFzB7SL6cD2AQd38Vt84KyRfFMMzSm3rqDiUMPMBiOtZ8RA?= =?us-ascii?Q?Io7jAllwArIcT/grNmlSQKX2JhL3qQl1FfDHHkzXrzLzYTnoORF+2BjbCE/o?= =?us-ascii?Q?TBmS0PSmrzzYZVq7B18jEq+P/grJWTn9tBsBvxDslPuidxIRfwZEl8xPUBXD?= =?us-ascii?Q?9wR+zjXq92c0EBIxCFSrpLS6UV7ZrKhpVhPOHrU6GJdQOuj45Ozo9ARMoUdl?= =?us-ascii?Q?RTSXp+LY0sbC5vg/D43EC41rd/L+RL8i1HgKoLDe9VHJPgioRwAyF8xJe+JG?= =?us-ascii?Q?1zXueV05neahgb5zK2hBiImekdLDbcA3F4l8AGFRe9nkzsTZHVMHYPFgAbc/?= =?us-ascii?Q?pk2kozQbt8csFC0T9kknIUx0ZL2M7X+1vh1ZDWKVxEOEpzpSx6jYWCA3yU81?= =?us-ascii?Q?4hrxe8adjID/DgVXu64hQXt/KDi+csvaQ5D8WacYQjTI9NpraiPykpUJxDF8?= =?us-ascii?Q?gbzBlXO5Tn/NLmIJ8fqoGlBNR5sQj7iDKqhrAYbhoui15nqY?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: eb69ecea-b7f5-4cf6-7663-08de9a37a69f X-MS-Exchange-CrossTenant-AuthSource: CY1PR12MB9601.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Apr 2026 15:08:14.4433 (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: y210mZQSlfDh4i9se/bNxN1ITTVBU0Er9T8I0t3d4yvTJymWF2uWjh6H9Eh5/jUi X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS4PR12MB9681 On Tue, Apr 14, 2026 at 10:40:39PM +0800, fengchengwen wrote: > On 2026/4/14 19:57, Jason Gunthorpe wrote: > > On Tue, Apr 14, 2026 at 09:33:01AM +0800, fengchengwen wrote: > > > - For devices using the spec-defined ST location, userspace may > provide (index, cpu) associations for the kernel to program safely. > > No, it is not safe. > > Thank you for your clarification and for emphasizing the security > concern. > > To address this properly and ensure safety, I plan to add a dedicated > kernel boot parameter, similar to iommu.passthrough, to control this > interface. The behavior would be: No, that's nonsense. The driver owns the tph table, nothing else is allowed to manipulate it. You haven't even sensibly explained why you'd want this. Jason