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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ptOcSKYHybIeOxFzxm6vawnzp4sNlFbNPIPoFt2+qO1QSiIDy+QetZ9YiX+A?= =?us-ascii?Q?HmYOvEXsmtHE31eUGY966PgB6+Qv6VxT8p7md+LYul0EVvrskM1XchLWAn+v?= =?us-ascii?Q?62XBEMhK5ct/8qaZ9XJSgamhVp/xLpOfIoXW1FpFnPX+/2XJoRuTWhjSKT9T?= =?us-ascii?Q?kNta9z78l0BNn/xo8hQSjH2wNzYGoGSS8oQEqaJ3gnOWSqie8Q/55PE3Ag4l?= =?us-ascii?Q?TJTcNTPvQpeG1odrMzRIhIl03g1fWIDHW+oe8BytqQJ3pa9nebF7yCJ7USua?= =?us-ascii?Q?XiL+XBwXHExtHuMaA5DWef5+T6TDuLh/eKyiar9Ij/Gdaa4Xo6mIQuSPzn5D?= =?us-ascii?Q?AId+ChdRAvp3I6C1CBzVCom+pKKYXeR6qI40TsH1i5+gj/gsgp/4ci/bt56z?= =?us-ascii?Q?teRTsDxvdNVEg0iZw3B8a6qU3bFqqeZFQcp+6ajW493rZCcLKW3L4jLR3Ib0?= =?us-ascii?Q?ygo7ismlFaeJS26GqvFW7bhPtQ2GL5y4WySUcufomxHdwWg/dOIxvii4z1OA?= =?us-ascii?Q?EVaxkyk1GQjFpgo/5s8okYY1ExsIJt2ifUURjp+OT0QgTfMpJNncsPZZ0qJk?= =?us-ascii?Q?L1boil3d8TyGs79ahL/Bz0knZHu1pb6lBdbtrOdrqMLAfHY8LJjGyTCE5h23?= =?us-ascii?Q?0eHpox3AmITBBZ1K/BqDzzavPAJdvbg51EKDOGaDW+Hz7JvTw72exRzpIVf3?= =?us-ascii?Q?GRQjazdo/Jxqq69Jxsx+sC+rHhZenOzmJ0z97w0YPuawuYYUkGG7f0HvGMQ7?= =?us-ascii?Q?1Z/CwDEqmxLDKrUkwWW5HqzhTU+utNuZHGGjw5rOaaGd+ioLTuhVviPf0bu8?= =?us-ascii?Q?gwfvxitAw+F3LxfE4kYX1/3NgBiAbTea3ig8UC/g92/5I+ED8MpmiKciwvdz?= =?us-ascii?Q?5hswa2NNDOZu3/rTtipTHzE49Lf7vLOyP3RwGIIf+PmKj/bcU3ciTgzdBEWc?= =?us-ascii?Q?m5W8FEfkqdfdijU9MslRGorTt2H7UmNWkbM+g7iWjD0tbhwa270vcM4rc+V3?= =?us-ascii?Q?vOVFfLSZlnTmoBxMY+ijnbz0P0IT2kxLCdCcdU9ua3SbZ+AujFWZV8CiXZjw?= =?us-ascii?Q?imFjVuC6kcGnDgXYYrozleYg/eBiOWyuZTze2YG2/stguJ3PsITN4t/9hoRT?= =?us-ascii?Q?vj1FMTMm189KCBpM7aDeWz24cRDIKdPg209SxyadgHUOXesY5v3HnwRjHbBM?= =?us-ascii?Q?Ed2vFcelbqLGQFwLvjfDyZdOlH602U0SX0L8J8f8d/4Ee4TbCpuKQoFFuL9P?= =?us-ascii?Q?O7u241RsY+wcs2nTKvWMB+FvWFlZYHW2UbWRa6lv7Isa2+8kIQ3CyB1oIH14?= =?us-ascii?Q?Bicx1xr2npfSMdYOLUhrwWg/vlh3RgpA9cLGD+O2u1az9nCwsCTL5z+b/WZy?= =?us-ascii?Q?bGNMADHziL/O1F9lgfGakzhvoX0sgWTIvNSonga8yBasYECPCi+Fn4inQ7Gf?= =?us-ascii?Q?rorhKle8Ei6KMFQfwZj0U2NBq+I28mePXTUfze0UgVeUv7DDXRl1yiuOWam+?= =?us-ascii?Q?DKyaLtDk+kce4fsAsCpxWdGwFRz7HM+kkX8bJdys7QWclABTcmSQwsoh6gWJ?= =?us-ascii?Q?apwVwEMGv8tDhk+wTDOg9TGDDK0hzkNJ1uc69WblUyUmIEAQm/9tKNM9IzOF?= =?us-ascii?Q?X4evL/AP6d6RQMkupsrJvxK38pJbpWkjQ4JAK+TUGVJXZOqw8aqM1hxkWz1U?= =?us-ascii?Q?KnlgJ/XLGgBUawFvd67k/Qmp4/wVvM0lptc+OWnC6lUFYQR+?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 1e66d3e3-6cf2-4879-0fb9-08df17e35706 X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Sep 2026 13:22:09.6033 (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: eFTg/pXhDSQ6v9MK+ofYJRfxvMfOvIXDSCaNO3/4T96C2TG54JitTLr1wcWy7G9u X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL4PR12MB9536 On Mon, Sep 21, 2026 at 02:08:47PM +0100, Matt Evans wrote: > Not quite; the priv->revoked flag tracks temporary periods of > inaccessibility. An example is VFIO resetting a function; the BAR > mappings as seen by the CPU and DMABUFs made from the BARs are all made > inaccessible before the reset, and made accessible again after the > reset. >From the importer perspective this is a permanent revoke. The right way to view this flow is VFIO permanently revokes the DMABUF FD. Then instead of forcing a new FD to be obtained it replaces the existing FD with a working one. >From an importer perspective it sees the revoke happen and then that's it, the dmabuf never does anything further. The importer has to unmap and start from scratch, get a FD and map it. That VFIO re-used the FD to make a new live export isn't visible to the importer at all. I think that is where this "temporary revoke" language gets confusing. Call it "VFIO reuses the FD to create a new live mapping" is clearer than calling it "temporarily revoke" which sounds too much like move. Jason