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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?FI6Q68YLrUrpJfi+iiMwsG7wwYPutIgbpto6YKklKspsadXE/DQgfpAmKWZV?= =?us-ascii?Q?3oN6UbwuKoUMIfIPxQAPgnpYz/81cIuPTpaP0g0BRrnrGyb3BTYvu1FQsE/j?= =?us-ascii?Q?DM3GvjHBAy1tszNFiPqOjPZUUIIcIyumx+opSaKhponWT2+028F+pH4uNjHy?= =?us-ascii?Q?o+v5dsx3ipWp+7VVM1WQKHRaJ2IQxdj90D2pnKZXPLbq2Yykc2qtULzMQnKF?= =?us-ascii?Q?Q7oC30FKiRZ/xTdxlugh1PBx/DGfgCQFXxbDQ7Jz/YX7kyv3qm6mae+iPC3o?= =?us-ascii?Q?GsjkLJB+1zqlrnTzgrvqqaEOB8emPWTJufTnvLVDW/b8K9IxyqTo8B7ltiPI?= =?us-ascii?Q?Q8avYaujOU/dzqWyPEi0Q8fj2vGC08sfUD4d2UVC8eUX65KKr737TFSaSoKQ?= =?us-ascii?Q?Neocm6ewszmbIFrrEgYH38xijA6z6j5L5QcMkoRdBLjZ2U0J2/QgM3YmPBSP?= =?us-ascii?Q?3NnNH0OoqpUgyWRu2j0FsaACFg3Ncni8YA2lyFXGkPSM/lc0FUde5sWUJtL6?= =?us-ascii?Q?M0nujN630YiORDFNfqL4ndSctXb9mXD6tsBJd44NnuvDbSsmdOD86mkjqHRq?= =?us-ascii?Q?aWEsByHxlL3WAxmDCmjP0vVfGi9GvODzfv6s7UDJdMdHEtyE+Hlr9cHVO5Ba?= =?us-ascii?Q?edT61Ns8COcNukTnztBNWjeqmZQMvw/dyD14QzhE34Z8XwkJNDW37pkT0TN1?= =?us-ascii?Q?AbtctDyxgFm+TpnVEkeZAmckSRgUVabCH01m31ILpE4xBG1hCNXdewjP6ISl?= =?us-ascii?Q?3XIOFjUela6NkwejhDHWCpNMNywuKB4po2Ihgp6nenO2Cpxh7ohCmAUWyvRv?= =?us-ascii?Q?gsB93scgwrREN5kDjC7RjcgTmv1jk68Ebda7FHGA/SVz4dsPT5A7Wl5IeKyd?= =?us-ascii?Q?L+ybFvQS0JNUgirAX6FPh7LmDC9BPCuScU0Z6F3GbZvnKsMnaWNba9HVQ+x9?= =?us-ascii?Q?d8GvBw0eGSw7mheaJ5svWFCswnGVodRET2LukSecTXQpYduXljB5/KWhiNun?= =?us-ascii?Q?OfeWi8osYE46LKOp7zeEooOlb0UFZJeV0+uYRlGqbqtGAwl7xpVIDh+emwVb?= =?us-ascii?Q?GzjFh6pKuNhD4ZQHLSc88vJ+Ro96xZ2/SbfWPG4Bvw82PmLHYhmUZlH7wpNT?= =?us-ascii?Q?jVSkrL0InlXeoFVrVGPq7MkTuk519yl49IjEmLwzj9cJT8s5aCLA13IdE04G?= =?us-ascii?Q?HUWl0BCREqGTUybu8AuCODBVAvMbh9rLaZak/3ahHspdIBgYAMpolTDnHCsV?= =?us-ascii?Q?UxRYKXXrk2lS6XK0pCocsHqhP1PoqnEw+JsQXMDFLeU7c7cUmliEPHy40EtG?= =?us-ascii?Q?ZB/M+aXilFiM8x1KHR2tgG7KCdoG48BpC16QgKQaQxlkt9zEdcLOwWZJnTJ+?= =?us-ascii?Q?LXcee4vAsqp1iF9ElBZATR2LlLTTSHTDf6NXxcPSJOxlO1I3uzBvi28IqoZF?= =?us-ascii?Q?eBQY05wFNiX6t2RsKZwUCtSgl9XJt5RxeJaNl/iwHyrKpdiCYbc0WUX3AcwN?= =?us-ascii?Q?4Szoj69j2zPpKcwtJ57nL0zsXBunucfWqn2s0XWkMM5VBE/4wXbjVmyBGWGw?= =?us-ascii?Q?kovmlH6Xhl6ZhQgVn/XvS0607t3OkMb2fOSAgN0e?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: cce18cd4-ccee-499d-d03a-08dde0e1ba9e X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Aug 2025 18:37:06.1295 (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: vs1ErMQy38d8Tl9tMUO1GbV8jVAsOC5tFeWx9aihJuikn+CZ2LiU7zkLVqiWHh0H X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR12MB7340 On Thu, Aug 21, 2025 at 08:22:06AM -0700, Nicolin Chen wrote: > I should have pasted the full piece: > drivers/gpu/drm/tegra/drm.c-960- /* > drivers/gpu/drm/tegra/drm.c:961: * If the host1x client is already attached to an IOMMU domain that is > drivers/gpu/drm/tegra/drm.c-962- * not the shared IOMMU domain, don't try to attach it to a different > drivers/gpu/drm/tegra/drm.c-963- * domain. This allows using the IOMMU-backed DMA API. > drivers/gpu/drm/tegra/drm.c-964- */ > drivers/gpu/drm/tegra/drm.c-965- if (domain && domain->type != IOMMU_DOMAIN_IDENTITY && > drivers/gpu/drm/tegra/drm.c-966- domain != tegra->domain) > > So, the check is two-fold: > 1) is attached > 2) is the shared IOMMU domain (tegra->domain?) Yea iommu_is_domain_currently_attached(dev, tegra->domain) > Overall, I feel this would be a big project yet arguably for a low > reward.. Indeed, we can drop a FIXME comment there and leave it as the last user or something perhaps Jason