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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xy8t3L3hERC3UXhz/6/8Qb+lRQqpNPd1Yo1H2zvq5pAF/zsHXsti0u1AnYBI?= =?us-ascii?Q?j8oLhsZA09oKqHkzwL1aDXZJ/oPkhzwavrkxt8eFqChq/vG6XVMdWFd9k8F+?= =?us-ascii?Q?IAKFaoMIAl2K4d7BRbMknCHxmS2UNru806wDrLmN1uIrmHRI14XWy9P8xim7?= =?us-ascii?Q?/yxubLos4B5iodINzYijAo+dNP+IWKghiLzLPZH5Cn+pOyChnARbgekSsYGw?= =?us-ascii?Q?dhvOBgz3chCAeXrk7nUVPkLfE5Tk7erCP3jHBhov9xTlgf5rHEPK1O/usDAr?= =?us-ascii?Q?4kQ1m3Oe6BO535u5M+izvwB2PyA4BDSS+Q+SzRcIUIpZzs8Z3zl327JEbgiq?= =?us-ascii?Q?un2Ze+ce1JvAPIf5tXxqAKVql1GZBpxMlnChyCMc1d58RrhaZ24TPsoeDqY1?= =?us-ascii?Q?xdFmWqOyYkvjILumpxmeJ1pJ/s50EX+2D0haKbT54L4+uzENlkwqMcxoF3LZ?= =?us-ascii?Q?K4D6PRbaCL4vM+s1bvcyUMoTSgyCFDmBg7nAE8T9dqtP/nkFb/68/adkAf5w?= =?us-ascii?Q?2liW2kG4pvDggA2/59hUx72a3LU4m4il55Nqh1bB6CtG9YQy+Vb+nEuCdeF9?= =?us-ascii?Q?pzeVgSBV+PIVVeY6BTovAYFStBPlglIvF8p5OwZEq+3VdyUJDKla8tlGUePO?= =?us-ascii?Q?VpVcw+i6QjFsea1p6OIxwGosFIcWVMJgWcjslByzT2puY5BJM9FXPdAwGKk2?= =?us-ascii?Q?BEnoVWGHjsFdlARgX3sEdio3/nJYyJzQSd5ONRuUB8n+feIdMzzJY7l4RA5H?= =?us-ascii?Q?iddydzQket/Habp3YRmIvE8NmBQkQ3nyMbgcpYQ9IGys5rgmXf8sRlta8HHQ?= =?us-ascii?Q?8VCqh1Gp5uL9NcXkmcPZZrEzoffFtSabAtnNI6k6G/NnnXjlU06vbR1uCR0u?= =?us-ascii?Q?tripVDeqFo7PReuf8d6JUby4vubi3LTmPpwOgG0SXHI9jxlu7JIGCpD3Dzon?= =?us-ascii?Q?e8/5nczo9S8PCuO6KevTdzXBJ795M0r8xK0JBTMxFoMmlDbqp6uhZl1twu9z?= =?us-ascii?Q?2O0p2B6R+SkObpu0S3QLL4FTT+/I60ASaS6aXNT3n5RTMyL/AlrvlPnO0m+7?= =?us-ascii?Q?MBnHSKZo8SgamaqRqZagEwhgNU2jy2E2CzB2fLSbmovQCcJ9028Kcc4/M9Z4?= =?us-ascii?Q?PZ0OpkTbaerkxzyD0a6/hl07mmKRrJV3CLCBKcpnBcVbUOOzK/pPxHNLGf/5?= =?us-ascii?Q?jOykvK36iS46AQzoAWM6vebBGj62B0aecW2HPWDHrusQmcj6Aoe6PLQ/pCt+?= =?us-ascii?Q?O5GK2HXKY8gIO5+BG8vDuQe+2RXJR++iT/0l8Vj06Wgt/TE0CZpNWbEahuM3?= =?us-ascii?Q?31SUOVZyxveU/Vd6tNbcQBJ2V4ZLphUDcjMh3ALnCMI3pLCkg3gyMjMD9EXS?= =?us-ascii?Q?ZviyGA9SHt1AMtOtVoRGJAl91C+EZztkZcrY4taodC9gXnodfqzC1LVsxESP?= =?us-ascii?Q?X4CkcdZcavSuiiHff3AiglqnVNbtARO9zvx14wJ9M9AdV/I9UMEqdT6451Iy?= =?us-ascii?Q?2LZUCWbJMpN5IEapBNi8YOzF+uXMNsQEQjPKjJK98VWdmtbBMm7lQgG6aHGc?= =?us-ascii?Q?Mu3C7t4b6OZ1lnkc33XE53OeJdf3XeUE7flRbGHD?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e74f4073-2a12-4b36-ca9e-08ddc0a2869b X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Jul 2025 17:44:03.5510 (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: sjpgw3jbMfTMqYZk0QQt2nVkdwPb8SVFiNIO6B1l173DY8L/H3BwX3hiG5YwVXhI X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ1PR12MB6123 On Wed, Jul 09, 2025 at 12:02:29PM +0800, Xu Yilun wrote: > Add the iommufd_object_tombstone_user() helper, which allows the caller > to destroy an iommufd object created by userspace. > > This is useful on some destroy paths when the kernel caller finds the > object should have been removed by userspace but is still alive. With > this helper, the caller destroys the object but leave the object ID > reserved (so called tombstone). The tombstone prevents repurposing the > object ID without awareness of the original user. > > Since this happens for abnormal userspace behavior, for simplicity, the > tombstoned object ID would be permanently leaked until > iommufd_fops_release(). I.e. the original user gets an error when > calling ioctl(IOMMU_DESTROY) on that ID. > > The first use case would be to ensure the iommufd_vdevice can't outlive > the associated iommufd_device. > > Suggested-by: Jason Gunthorpe > Reviewed-by: Lu Baolu > Co-developed-by: Aneesh Kumar K.V (Arm) > Signed-off-by: Aneesh Kumar K.V (Arm) > Signed-off-by: Xu Yilun > --- > drivers/iommu/iommufd/iommufd_private.h | 23 ++++++++++++++++++++++- > drivers/iommu/iommufd/main.c | 24 ++++++++++++++++++++++-- > 2 files changed, 44 insertions(+), 3 deletions(-) Reviewed-by: Jason Gunthorpe Jason