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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?QiYOMshpkpEuEFgzmE1bwDKUb7KSYnhfr2aK9lFRNhhe3p1LWz6jblJjfN51?= =?us-ascii?Q?ndUP8As6UI9tn/3jXb9+DCOVElXIeYkmDchvd1pzCGzGoUYDWfa46ZlYuGwx?= =?us-ascii?Q?pcqYHschdLlFem6apqhSYB2MNM5UMkWiYsLm2oCJio0yyIxtKeOYDU0JGM+2?= =?us-ascii?Q?31W4z608zyS9hY6H5cGO6/OH2LfIdoc0LkJUmxlYmONr1qK47Nq4icWO0q9C?= =?us-ascii?Q?5gvik6jr/wuzkEf/Md7igrvpsSRBk4k9nVdGQ+9M9NCXZnWm6pd2EEZa6aDb?= =?us-ascii?Q?TyCWCbqEVSyeYcxI6uAJfwxZJgbY6Y1JVGSsoEGpm4BoFkxliaHE2tFDPyks?= =?us-ascii?Q?jccoFtGBF0tEJBdvDuBsU5H7sRZcIHZ3V84Slhkx6Y7ZJgM6PSXd0e6jKMrq?= =?us-ascii?Q?6EecmQWC4vHQa20TfGkoxvyTBchx0Zfj5k8Dm0c7qFZKuwqijCTt8fqVwaaU?= =?us-ascii?Q?uisyIpQlPiDIm8RgqaftnPxmBx+/vwOCbjo844etwptW312ZiN6aA34mE5Di?= =?us-ascii?Q?eu6qoLe73X14BoeGrAL4W9+8MdeuP0w0b7gI+Or68yzfDs2UtcYsApfQNSbD?= =?us-ascii?Q?V1r1ZEbMpenUDJmy1JWLwMop6MYuj6Y6Yae8BPwMb/5Q7wi2VRME9WzcJS3J?= =?us-ascii?Q?UYHdVCGsLxvObHWErJnz3KZ9SKABqISngHaFc4LCvyhSpHd6T/wcfoLLCFZJ?= =?us-ascii?Q?6Pdv79Muj3P1hrs/4t4zX+uuk2H0CMQ5e8VT6dWq2ecp3FkuBzNWSRHKgLx7?= =?us-ascii?Q?6rlPa6+S1PgO8NVJTfpGJ8ShFKr3mbzsOBtRm5IJJ17zQe0eo4JCtwUFsVgE?= =?us-ascii?Q?H6xPxBICHDQcUNX7nLfZNDjJso37ZGE8nsxuWGJxIq2a+884WYOyESXCwGHo?= =?us-ascii?Q?ARWP3pK7NQ/snDrm0HdS7vW3aFxYuUmnxYdN68oCMghnvy8VafJ53viHGHNt?= =?us-ascii?Q?J6X3NhJfKR1kTNkcx+HzUgahCBMMQnOyt6thI8oNMX8cdWFWGuqPQJBNhjjz?= =?us-ascii?Q?4pSltQJc7cwUAzkV863W8/iCo9RBNuprRbqcDZMSkjhj8T6aYNcVx9sVM1vU?= =?us-ascii?Q?yNYh2c7NqcFRFz+5KWvrMPn0BSZpzCqjbp8dBHRgGA2mYzU52ztMSGVbW/f2?= =?us-ascii?Q?C2gCe1OxVkivGGvExwob3hcs4GZMmTLMZWw+RWiLbQBjoer+kz+mpoN7FyNe?= =?us-ascii?Q?dXClVn+tJUML5ZeIUwBVv0IG5xCTPf9Bc1yDrp0rJZxwXDPRM90BjJ1ZqySz?= =?us-ascii?Q?zwRtL7gbtkey4CMiAvp2pGQmvfRqveOStWe7o1eQUfc5Wu5/ojaNBys98hfl?= =?us-ascii?Q?O4I3L7kxQAbutIQSO/uTVsUi1FL+LwDsmibh/HNIg81tNjQP77/mGDBjnDl+?= =?us-ascii?Q?svv/kSEtAbLAigQjB+TnRB/nkMIgMoo/804/wPh0dJ/cGMSGMquf2O0fleek?= =?us-ascii?Q?Xt+1yme34WrNXiaeR63f+bIfU0ZqoIbxMsSRWJQSj+elc6tKske8cYgYKtsS?= =?us-ascii?Q?pGnrwHbUYXUaitF82dIOwsb9HjE1ylEbDs2YslNDngoUHSSFJI8aIMsxmi2l?= =?us-ascii?Q?DTmikXBYpCYXEZUQVqtW3dvXTOV3w1/WtkzUpgTu/fqzENKWuhXdjxPhqBrf?= =?us-ascii?Q?2PK3//a3QkHjQvx916/oTfNCULvHhxx4WrgeYohfBKkxnLyXWmcM2RGB10Qq?= =?us-ascii?Q?7C3/USsC9xxk7D4uWLz/K0bZCTcAqpIFayo/jOwCmBNzlcqj?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d8817f70-210c-4f78-780c-08df3071a6db X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Oct 2026 19:21:19.9557 (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: ejvkqHqkWL+JZcMM7S+/sniG3bsPmihDmGv7Q52T1K91ZMUipaz1euPbA4pLNve4 X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB9468 On Thu, Oct 22, 2026 at 10:22:55AM +0200, Jiri Pirko wrote: > >But it does work well here, and matches what rdma and fwctl did as > >well. So maybe iommufd is weird. > > Well, one CTLV chardev is always backed by one device. I think this 1:1 > mapping is clear in the device model. Iommufd indeed looks weird in this > matter. iommufd doesn't do 1:1 with a device.. It is more like netlink where it talks to all the devices in the system concurrently. > >> Depends on the user/subsystem. Either families_dump op could be used of > >> udev uvevents that also carry family inheritance chain: > >> CTLV_FAMILY=ctlv-attestation-tdx > >> CTLV_COMPATIBLE_0=ctlv > >> CTLV_COMPATIBLE_1=ctlv-attestation > >> CTLV_COMPATIBLE_2=ctlv-attestation-tdx > >> CTLV_COMPATIBLE_N=3 > > > >I wouldn't try to link it to udev either, by the time some userspace > >uses the cdev the udev information is gone, and may be unreachable > >from inside a container or similar.. > > This just gives possibility for udev to work properly. Depends on > the user/usecase if it's going to be used or not. Not sure what you mean > by "udev information is gone". Udev might use these uevent info to do > aliases, similar to dev/disk/by-* I don't know if you can encode N compatible strings into a file name. And in a container or something you can't get the uevent, so no client software could rely on this information. Jason