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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xQ6rNBeM8nEmGjWxQAHxSTQhMZ4pw/RLSBFSd3QlfvY+taxBGOwuWQCDmcPK?= =?us-ascii?Q?H4BBvzA5Yi8apcGBO/uhDTVxevUN3DN9sjCi/b0YarphuNN7L8tVUd3xishM?= =?us-ascii?Q?sd741cZu28bysl1OZCyPTZlgr8pgiWIOcy/FxRcqdABVHIxEjSzwnwwuS6kj?= =?us-ascii?Q?psegZyt9cf7pJJtetQNL6HkvB9Hbyep6WUZtyKGCRfhhCsTM8ZwPRUVW7K6z?= =?us-ascii?Q?a9ERuF+RxOE3AUuk8tcuFdQ898MFgYzyVsNC+bFz65C0Zi7Qojne5tjkbfy4?= =?us-ascii?Q?GoDxyqpzv9gJ0pFwTBb7KZQmlIhyiFD0OQch2mvT6bbgIRZlISJRwKMXkzOL?= =?us-ascii?Q?Q27ecP5iOsiX3wMxQsGlkk8+EvDe4AhhZsGVbZYuYKzdSGTIE67K32gzhcBb?= =?us-ascii?Q?Mj/VonQidjw3wdMrQ3swXkmB4cIleDHKIiHWnywRpFHrhY08j2tDNc93U9GN?= =?us-ascii?Q?SkXWpbg5v3zUOhkZ+55IhTPFgN7bQSAIYf6a4W073DOkNYZ8xUBLPJqUsiAM?= =?us-ascii?Q?MBGdQDxw+JzmVOdkXFByHzhF9kuZ/fjBgTrE7m2a4A4dBnhCs4iM98xwA26k?= =?us-ascii?Q?uPMCdcTedG9ml5vpxuEI2/4U9knkAUg0jGBrwNUkLUDRA7sRkxc0QNIImd/E?= =?us-ascii?Q?wp+WtoFetxXjDN1OIoee7E5sN5FcRCuLtglOZbqDLAKeq2m2UVbCJskc2kbj?= =?us-ascii?Q?UEzStLEe2b9+zCrZGvWCnHB1jJfzsuJHeIKrHcVLw2URkWOQ+ZFMQ+T5vxDQ?= =?us-ascii?Q?2PzyuYDNtntd0sie3IpW3NgM6lMj5FGaaa8MZPzYMPCen04uOLka8AXi/OQg?= =?us-ascii?Q?Jv87xJVDMLiTi+QHUp7rhL4TKGGSlj5361Ba8AVzbycFFqEgVkjN1c+C0fp0?= =?us-ascii?Q?YsHp5r5r+qDrRcHcFxqkms40oUx87uf3ojxim+S40vCjMhQdejDlLhekUdYg?= =?us-ascii?Q?mwase4HbqsjiJEvitLR97BzOsbEcHZChSmKYnyWv4lukwQoJTKx7npqJRs69?= =?us-ascii?Q?BrxC3xnYU0vvUkwmzvps+A5Gi/6aE3JdZQkxZUssFHMTMlmeJTaw9HPCCjfM?= =?us-ascii?Q?Q/5OAm1xg1GlHE0uIDNjm7exyfTKAq43ZE912YQsS4r31rdASCVPeX3BLVXY?= =?us-ascii?Q?L2I5ZqQpTo/4CL2Vw4DrBOpjUcIcEjoAjU3Fza8pH6FE5DlZVy2dA7s5zyTo?= =?us-ascii?Q?AUyz0lspsEATnIJEGFfnvAjh8W2dToCST+XeF4f2nuoPMefip40am9yPVJZy?= =?us-ascii?Q?VUVO14oAe5xfDXWnnj1fak1v5gKbFFQNWWmR4J3lLtp0GnwfQMFNipafzDGO?= =?us-ascii?Q?n8k0TXgSSHbG3eXqXvN9c3MNIV59IMubA5LCuXsesj6qGW6qavo2YlDv/k4r?= =?us-ascii?Q?f9HWt0iq24Kmv+CV56MxsLJgVAdyYpzP0aCrUdEjErXnnenQacrWUHRwu3yh?= =?us-ascii?Q?JEpnBJlfpcWN4Y+jDESxHO7G522XiWfWQsGxdqBzPXEnFXrbZ8Hcc5Y73h11?= =?us-ascii?Q?G27GVi6wvcnHO1lpI3V7ysjOtOLWDH/2fCZT2AlYR+N9QDsbjTrVTXOORolo?= =?us-ascii?Q?KL7/KQg8tXnUHwU7nM1IULCzA9BBF3l5O5zMqLcL?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: bd8a9e55-e957-497a-eea9-08db8f682610 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Jul 2023 12:42:48.2607 (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: h/jXrLBR87p9sHDo9JU1i7M+hzV/z/Djl3PI3K0G4clPZOHeYPZYjZa7xjNyJ80o X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW6PR12MB7070 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Jul 27, 2023 at 11:33:26PM -0700, Nicolin Chen wrote: > Update the unprotect routine in iommufd_access_destroy_object() to calling > the new iommufd_access_change_ioas() helper. This will reduce some risk of > race condition with another concurrent iommufd_access_replace/detach call. > > Note that the behavior of this function call is changed: a WARN_ON will be > triggered by a -EBUSY return code if there is another ongoing detach. This should be completely impossible, at this point the object must have a refcount of 0 so if another thread is concurrently detaching it we are already UAFing. Reviewed-by: Jason Gunthorpe Jason