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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?7nRaFKqyJ1AxM/hcmvI2CWjbR39D8YrLsrjHdMzHe97ygodaJTHEDM3DeSL4?= =?us-ascii?Q?eTDW7ZtZDs0H/AYlarTPcP6kJMJRmpvMXRAK5hyYfUbiUWYXhHrsl+u0hdcx?= =?us-ascii?Q?IfoIbKB6ckm8jOBFf07tosotisIdgkGMS1U1RD92ikgWlj5TH/8vKuJwTt5e?= =?us-ascii?Q?pFMXgkRzOpfs/44Pzr2N3yFlzpo+fPyg6pM+WsMX787KA0FfE+ybFloS3Tde?= =?us-ascii?Q?ZRBin/RYeKAC0xO9QHXJelZjhTerxQfHDmFY3nhSqhnoGSAeDXUdlemKwhiM?= =?us-ascii?Q?S9pJmyN3Te9Hh8yNHkyJkftNRhKimYtdXeFUVn15OePGDwXo7/6N51VB6MmP?= =?us-ascii?Q?epzeOcq2FWDtrZxUG8W4i323+g3bx/L8vpvty78JCvwB+2LmlrhmHUk1Mkbt?= =?us-ascii?Q?XB7WQx047UeIGxJ+oNWa3t87o9weUs+UyKY6Z2JUcFjwy6Wv4tWQrmbutisz?= =?us-ascii?Q?tg/MZ1e+UQQW+kNthlDODyOdvgBLSJIprPz5sU9dc1hom+QKq6GJO/ujvfx/?= =?us-ascii?Q?kD4gUhByDqrlYmabZV+qOa4SvKsSpbfX+IZT9yUJ6EqYretiuxk0lrJpO6LK?= =?us-ascii?Q?d2g5W9E4TL3vBb/79kxO1zVQxpbdI5ELhpfI+9HMQNnkSo2xOJGMsaxeqWQB?= =?us-ascii?Q?58cX+vydMj2ARUaIefOlY4o+tbuyRX3mgzoyijLbS/OgUxdoXCRd7eSFOtB/?= =?us-ascii?Q?d5bTOkVonse1Y3h2W0Zg2Drt0oeK4iSrG8Z+zWNSJMK6UcLmeKsAv09glLXd?= =?us-ascii?Q?8vIZtQzt8w8IxSQAaT+Ad3RnSN8h3gzEX0NfgtiUgceF/YfYFSdlefSVvFgV?= =?us-ascii?Q?szDldG33V7jZ8xLy9ddJKQr7yU8nn2+NsmzIk8/OVcds/ryV4ohO36fKoZvz?= =?us-ascii?Q?aeKtKsBqnBzK2dQju19O/FjdAdN9vYwJ7WuVGCKuXUjd1hh0KwIRcl9OuvC0?= =?us-ascii?Q?M9S+Jor+7pxVubgfB3ba3mrE9GQSzvgV8w7ZdH7QWpqm3o7bE1JKggoyXlCH?= =?us-ascii?Q?wYbqCe1gfv5S2YAW9LBKNaABLnMpceaUB0CWGPOVuiX4p+AHM4Yhi7xsqf9V?= =?us-ascii?Q?OWef8gJaZZbY7ZA9sgsF0/Sp82vZn2LhxqXWLpPXo2I0IHwizIG+q0rkgqx2?= =?us-ascii?Q?hiUizrbjfK2CmZmSnCADJctrW9OMxQs/W20S75A+T+l5mOW7XRZbc8+WpURO?= =?us-ascii?Q?AMNDIM+0WPHCaa1e7/mg2FL4tbJB51NoFMAxrWEBsGhvIy9qgn67t4DYVOrC?= =?us-ascii?Q?XZ/m8/wtW+XrRPcE8RYY6sxWR+5sDlQWiaScogXzp1wBTtsAaXjDYt4JfqcX?= =?us-ascii?Q?SyW64B/od8DWoCxuRyrCuZV3C/1mqPqjYvXKTcrxj0jphEAOQwgitrWgxdri?= =?us-ascii?Q?CS3ZkcVepZad8n3AEwLdqT0xizil9zj7SUdP3l7mUAfpS6q4yFLjjRYISJwe?= =?us-ascii?Q?/tRnrNi4KVPCAx0f/fzwxiIJORu5xiRz3fCR70UqKztgN1zSvWk4t20tXqNl?= =?us-ascii?Q?hQX1T3oXSIizAb3TfAYQ1g712T4ISbOUzODHEn9a52oNFxkduki10c6T9zWv?= =?us-ascii?Q?8ji5NSpdpkitlJ4V9EAN2RKHhnbwCEuQ7vZmytd7?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 53c22fbe-1ea5-4523-6413-08ddde62057b X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Aug 2025 14:17:53.8915 (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: ZG/dwyIC+4KKlmOJmQIzyUCc6TN0S83NZPd3854cq+LhtFLLKm/ThwcjUnJVTOsj X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8832 On Fri, Aug 15, 2025 at 08:24:57AM +0000, Tian, Kevin wrote: > > From: Nicolin Chen > > Sent: Tuesday, August 12, 2025 6:59 AM > > > > The iommu_deferred_attach() is a runtime asynchronous function called by > > iommu-dma function, which could race against other attach functions if it > > accesses something in the dev->iommu_group. > > Is there a real racing scenario being observed or more theoretical? I think the commit message should explain the actual reason this is being done, which AFAICT because the new lockdeps added in following patches will fail on this path otherwise. Jason