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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?cx9bd1RUVR6B6gzOX3YC0H6trKkQeIhIOPZMGy22qOT2Z7LOmCTi4P75Hqg5?= =?us-ascii?Q?GN9ftXMoBd6w06PQkD4TvBqpT0uYe7EOnpoqfEbcydMGY8JC2jQ9SxBO/CpZ?= =?us-ascii?Q?AbdYBGgJXtKbeDucV1SqJESeN82wfMIUe+xp0nrQ2fzCx/r89pGUCFSsKAdd?= =?us-ascii?Q?uFei0GgfLlMik9RnzanVUs/qmoK0PXOxA1lSEectiJx3+7EiOJFhrY9EI5QJ?= =?us-ascii?Q?Ao6tavHOopYbf78ew3EN77wLLe+TWZgrESDJoWizJ88e2WrZFabZvaIZx3SO?= =?us-ascii?Q?JDRsdCZhsId9EenhQbsEEouzA7+nH8NyGl0RN8vlxY/hR6q6Sc1VMurS3J+A?= =?us-ascii?Q?UZNmBlVU7uXYe65agJgGxFzd5KUtdHq3UJzK+AE5IiDTMBjiynegarzSrAo1?= =?us-ascii?Q?/kRp+jWCq7BtVeWvCV0OIokfGfCBl1yvklm0aWLvACxOqnbVsQjwWrlM50y6?= =?us-ascii?Q?gR9Yzvr19b6YknQ8DVztsUAyvFm4USqSMAfB1eqc9ldbPJoU8s7EIA0mjR4+?= =?us-ascii?Q?OE63jwQFBxQnmTfuAYNqhJve5YC9m1hhuXfreW+0sVZFLrXdunLsbF4cZF4x?= =?us-ascii?Q?HUO9yAvMXywztKXvEMBbeJA9+z8RHzVyVf+CNE/RKyRuDnCOXDWalnVhoW0G?= =?us-ascii?Q?Yz6b0SAkTF3LGQ5/HJQj3ZIwpDkLmiFowzAbqkU9xYTleojhurHdj0QqV/5I?= =?us-ascii?Q?OR1u10jeQWi8ziHGBfYz85T7Q14/7XY4opxaNbEoU0saumruluGd4TxsqriM?= =?us-ascii?Q?xVS3k9Bxm9GnnxhIeGXIb2ThR2L3rhoRHAySRTGlYN5Wm0sIlJxhQPirWkJb?= =?us-ascii?Q?Y2r/RdOwpUiXsFtjuX7JH+oZcN4G1wBdoEQ4skHBezZz46RB82BUtL7CHnGX?= =?us-ascii?Q?ygD2Bx661QS7lfvYZIC80Jjhe+u5B7QTacfqEWFieF4AkMxkNhHBGVw68WOL?= =?us-ascii?Q?rEnX9Htc9Lx89hxiEhhsc5wt6w92hMM0Xnj146+GuCwobG43CWP0MAG7cbNb?= =?us-ascii?Q?l/XTO74nhQrMEvyTa3/s3DUqIwBCetHRuVRbpXiT1oj6g62CJt+8j/6y3d1Z?= =?us-ascii?Q?Kx4AITNl4wITVAkdXnVv8Fx5FFl1QU3vMGf0kkujoWKTkOzok8ZRlm3IVz3z?= =?us-ascii?Q?aPjVBe91n2hwall1Krn23eJUtR9HWIjMiYxrI1FyGgcPc3SXvRWCZivlhIAy?= =?us-ascii?Q?7XvEKsUxP+OWkuKy6ddb2mChg1lNCbuchw7JWNYupBbmpmwKJz+Q1JUIGWOF?= =?us-ascii?Q?/4e4L0wDyszFxuQcu5mEFYIAxnCHI4ZFnF5kvrE6kuCsbpdcxZSxVj0tkmYC?= =?us-ascii?Q?XK1CU02vZ0ZA3K1fOG5E06/BkPRJiMgIVCCpEmYyT5lBfpiycuAlYerTwBPC?= =?us-ascii?Q?hV3pheicupg2web1hL3km9E6TLH1+dgex7fienvijSakBlY7o9LfId/eeGx7?= =?us-ascii?Q?LYW9N93Pz3m12V3iHawWzGEVotwsYtm/mzfSiwZF1hv8v6oaJpR4DtWm74HV?= =?us-ascii?Q?AkKZosk9jadiEIfMkEo2vbJkpzYSdkl8YIlWiyEd6csKpYUx5fYy1bDPs1eM?= =?us-ascii?Q?DZxO5ctAXJpqk+Bswi8=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4d41d750-81fb-4edb-b981-08d99ad9e80e X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Oct 2021 12:44:54.3855 (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: pj8naDd3dda/DY+F+z+qUZ4Jiv8bmq6BG9TYA8/Zv/pe5Q4Pyz/UP4PVTHL7AIrv X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5288 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 29, 2021 at 11:15:31AM +1100, David Gibson wrote: > > +Device must be bound to an iommufd before the attach operation can > > +be conducted. The binding operation builds the connection between > > +the devicefd (opened via device-passthrough framework) and IOMMUFD. > > +IOMMU-protected security context is esbliashed when the binding > > +operation is completed. > > This can't be quite right. You can't establish a safe security > context until all devices in the groun are bound, but you can only > bind them one at a time. When any device is bound the entire group is implicitly adopted to this iommufd and the whole group enters a safe-for-userspace state. It is symmetrical with the kernel side which is also device focused, when any struct device is bound to a kernel driver the entire group is implicitly adopted to kernel mode. Lu should send a patch series soon that harmonize how this works, it is a very nice cleanup. Jason