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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?1eWR1DoH90ciC/q44Fcy01YXHaZxyV1kPzUHUDArvZyZWAOpvq0/ErnP72We?= =?us-ascii?Q?NX5pxPwVNWzCfmkGR8TxpjoKZ8YVgTtk8pDRoxE+zEwxq3qMpHuV7PbSNPOH?= =?us-ascii?Q?OUDD4Ku2YFtLbiftY2af4cdVhQksoD/+jRVk4BjPb2IJtdLnOQA79xzaGhGu?= =?us-ascii?Q?INeUs0aZBdWuwHpYctQkuLikTrpyG2F3R+VUEk/5cWNNdIh+rz7tnA77vdNG?= =?us-ascii?Q?zP5lBoaSZ9BUT2e5f/2v/s1jObXlspmsbDMu8gXIlNP7pvFzOVaVcFAUWbOM?= =?us-ascii?Q?cc9uMZSTYcsDZGoGNTeyxt5bcLsH14LTvOiCosvjS4n5Dt1cWqxNneLKGYbJ?= =?us-ascii?Q?Zrq9XK8L6qCfMIn3jevRCyQUGflyuWeW08sq3kJKHw9GhFgW2Zl/TLrYf5Ja?= =?us-ascii?Q?hs1mPkafQnv9yFB4j+onNkGgkOlzpnl+fCsBVxt8hEsVf3b60kR7kAjPhZ/C?= =?us-ascii?Q?qwp2cVzJ5deFHBffjrKoRTrIGKi5d9S2zaJUfWpLd0QFiAcMTSvjlbf7CX0s?= =?us-ascii?Q?JlOmG32xj/JP3VG0F2oTRZ0vA72b2D7a43+fFDwxbIjhjUE+pIYBd4xha81v?= =?us-ascii?Q?GOUnvcQmUH+8nFE87WZJRKmmOnTSBLBTg0tzUzapcfG/TXYY90Xmwvkh3MSK?= =?us-ascii?Q?nkY+Ot7vmb3M4Y8ZzEWbnFc1m+f6NPaLSllY8cADOEcczmNiQ+3ca+QrkZOp?= =?us-ascii?Q?dfu/wfs/os3SxqUFrtXFE1g4ViQeE3a47KXcSoFgFz0tRDybe8Pk9IbGCyvs?= =?us-ascii?Q?7ZWkqXiUBNv5bPwwwKjEAj8CZT9A2E3oV0OOt2LaAPfPLBBq9ZpQoicjSPH9?= =?us-ascii?Q?WKk68fXsShkzw7Q9w4Wk6ZH32qbHM3KwjDsCz/fwgCtWMGzrLNY5puTkcGN4?= =?us-ascii?Q?N1RwSph/1+htqZLR8iUwoSY5tEBLNFojfpK5Rtd5FJxjWHx+p3bR8rZUhgk/?= =?us-ascii?Q?xmo8StKGdOwNUyXh2ypMJlfG64AGcjqrXYynDzHLp+T7YUUQNfpJkW6oxQg3?= =?us-ascii?Q?VSLKKAfGe4PUnlbcoDaOeHa/d2PxTHb7FPG7aur5iHeya0xYcKmXEiq5iBGv?= =?us-ascii?Q?JxXXGpOccqFwHOZ2pWPALojxlD5sZAm0IRacV7s4zes3Q/Xa0ATdPs/gzuFL?= =?us-ascii?Q?Xm8waJ4rt0hcS02S1PgMmJqtChblCyznSob1e1uqgkoB5vvO/o9LaBoBMzbW?= =?us-ascii?Q?BUEUEMOKd/kmJXN5I3sFfZ+885TtdK//gVWBKWthMFrBcbUY/yd9W5aDqbFk?= =?us-ascii?Q?Jb/3RnYgD0A6udaZCtrNUPKssM+mE2iFPHpZ3uOK34xwJ3UtJiKI2o6vVQNl?= =?us-ascii?Q?06m48DjOS+bFTh9exOVcUTxM2w7FJ15AFpWTP8PA0xTsMBI7fotwKdqzszBX?= =?us-ascii?Q?6wfsUkLTtyCMRY4FFmcKPDlhXU2wCB40fwFTyH/iwg6D5eQTQqyWMN3eWIDm?= =?us-ascii?Q?gKfF0mUXccC9aIqfvpJytKhoEsMT3lLDFBP0uvyqsQM1WnSLCkbWbFC4NZ5F?= =?us-ascii?Q?TQqLiVCg/lhP+VkLwbLilE5t8yYG7cmidxL7R+CZzll/oaCXbym8ZNvf3vRw?= =?us-ascii?Q?ShGecnxtXrJepKzvLCM2kiruJhArrScgx+8hXvC2XuPoMDHPzlfZsQlVzJPV?= =?us-ascii?Q?DBp3Gurre4WbIxEpEi/2TYJBbjyu8YAVIIPEmue/DZ0gGtGWCc4w1OaghB0Y?= =?us-ascii?Q?F5pDTzvw+Yls2MSdOXehResqEFueEWrEY/SagLDkJ1A/ZfvF?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 08bb8c57-35be-4f26-3de1-08df1325cca8 X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Sep 2026 12:35:17.9141 (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: In3CKsuJIK9HVNWhsULaKQyIWFknsB3uMtJwga4W+84G3VTjUjBs0getdHio/8Oo X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR12MB4415 On Mon, Sep 14, 2026 at 01:13:36PM +0100, Matt Evans wrote: > "This is useful for lifecycle management, to reclaim VFIO PCI BAR > ranges previously delegated to a subordinate client process: by > revoking, the driver process can ensure that the loaned resources are > made inaccessible when the client is deemed "done". The original > DMABUF is defunct, and BAR resources can then be safely re-exported > for use by new clients." This makes the point clear, you want a way to permanently revoke a specific dmabuf fd and render it forever unable to access any underlying memory. You want to do this so the vendor can fence the vendee without requiring its co-operation. "temporary revoke" ie what VFIO already does around reset is a different thing. Jason