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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?llu2qpY0s2eoOiIYovn16JfEgXyp1x0Gxn7U0JDa+0i3kAnV8nqg7XSAbN7/?= =?us-ascii?Q?V+tsS9uSrj/TsV3Tm8Mx5zcWQ4W/i11Zy926inoQyE/LfT3Qz5GeFkuGII2h?= =?us-ascii?Q?BynuplbFA6935+w521aezby7ew32jdHjQ6VVVl2YSPg4I/GeEZE6NnlJZZ5S?= =?us-ascii?Q?5IhoGo1HmW16I+23AhWU5ndMTyV/Zv7BG8vlvSFWYMsEUWcvcpirwWx3jjJS?= =?us-ascii?Q?Xb7OCR/qmukhWiRXnrb+/lXKBqURK/G2rArcbHxkJu7Fe6+lie3eCDFL8JxD?= =?us-ascii?Q?ss45yoDEAyHme4UuOyq0o9jznI/phOB+JrNBCidJ+HF7m56DFx51TOQmwjjp?= =?us-ascii?Q?GzdqjEXbUJitfSyXJuG5rUyrEqzr814wdWqJHQhoBnC80uhfKjqf6NV9+ox7?= =?us-ascii?Q?vaaaO9LNJYyDbWCwiw/Z4ivl0rWv9oscoL94QzWbfGSKvgDlu5lckEUn9/oy?= =?us-ascii?Q?33DbUWm3IOLnIpjWA5ZSnnUcR7fJYAFYoJFdCNcHFWNFiZUDqBTyRrrjE8Zr?= =?us-ascii?Q?Kvu2yXT5K/LJGBh1Dz6Ng2pKs//QRs3qpU0SChG6/+igEE7kFpkqsalcnoSY?= =?us-ascii?Q?8YIHXUByKCmpvxY5wIAmHXGDM3mkJGAQioJnm2C+7PYIzBD8Ufo20Vdk19H3?= =?us-ascii?Q?F3Ny+gCs+oW2Jun/pJu812IJHN4XrXVR9TutT9fn9rPdn6s9j+oXHFl6DFI/?= =?us-ascii?Q?q4ANsNvYuvIChBUqzjBXneNedZhK+iUTvu2m16uEcZeTPS/sReoOJ3Pijkt7?= =?us-ascii?Q?SR/ssJSl+2lnNrU9BM+1vqHFyEzCPUKqPpbddqkwzUZ5jiQBNZzfTnHXg431?= =?us-ascii?Q?1FLWAT2mHnZzduvBEctN8dFjnRUUqz9EuLL1Ya9EsoStMoDyLy3Wtr6PXjJE?= =?us-ascii?Q?+qsmf5bZ+e5AFfYjwI4qCu4I+vwrd7PkT8EvAQnLfXvNgF0yJpIlHQn+lkDk?= =?us-ascii?Q?rcPiiTAmnZ8gBalNGxNWxRgtJoN5rZLyOiaTILhfq6v57d8Y7SZP17g9EBsY?= =?us-ascii?Q?BQMfLkrZGKSBKTmKgewTvEAQEJFAPX3ZUua4WPHaVcsgiQuJYcvzJZ6aCCET?= =?us-ascii?Q?1lldZwP8x7VIbtwgqB9SGTkG6sHDtgtxgofwlZeKajM+8fLGs4R7KuY/ahNC?= =?us-ascii?Q?OmMQdPrcSEjGl0D+BbGO4uUAFPZfacOWx6YMgdYyffyWge9SEUtjVJNEOiZP?= =?us-ascii?Q?QfBRj9vGxD0G9tv9NaQkCREJRRudmpxyNFXsSWLqMKXYH5bf+zKnhCIV4N/e?= =?us-ascii?Q?g7SF1EqML+ENE0lG0OewixIHDtM+SCIgvAcmuKLVXBcxVGGFCQS4Dxbl2Atf?= =?us-ascii?Q?F6nq5PCHyCNSwAdFrbG+ynGkAUHQcpS7yWiuCP8rajW2jEaMQAyQbjpiBsqU?= =?us-ascii?Q?IDFedulN3oAaBercVL9LgeL+ylUrHWZDYa6Zp+l14ydCGRkiQz+1xQfh7dr7?= =?us-ascii?Q?nQz887L/Wj7f7opXPErLaf52+KehGwebIQRSyYgbqpwGeJIEsMt60Kv9KNMM?= =?us-ascii?Q?VjxYCzs+WsHTm3QWqZ6GOx3kPQmYgeMJTvfmCJ+oSjogaX49ll5zlBKo4pbk?= =?us-ascii?Q?yiN8VtCjRDFpSs+PC9y/EzzkYnDlAqJUe7apPu7L?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6dc089ef-f2f8-41bf-b3c3-08ddfbadac80 X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5757.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Sep 2025 21:02:30.0895 (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: FR9ue+xgoyRVvrOoIkk2uaqr3m6O93ZubObdMPfJqo1B7ZhQmHA2NI/RW7XftyRy X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB9194 On Wed, Sep 24, 2025 at 01:02:54PM -0700, Nicolin Chen wrote: > On Wed, Sep 24, 2025 at 04:52:54PM -0300, Jason Gunthorpe wrote: > > On Wed, Sep 24, 2025 at 12:49:14PM -0700, Nicolin Chen wrote: > > > > I really wanted to say this should just always return the > > > > default_domain, but it looks like host1x_client_iommu_detach() is the > > > > only place outside the iommu drivers that would be unhappy with that. > > > > > > I suppose any external user that allocates/attaches a domain has a > > > risk of potentially using this helper, in which case group->domain > > > may not be default_domain? > > > > Yes, host1x seemed to be the only place that had that intersection. > > I meant, we cannot prevent others from calling it like host1x does? > > Even if we have those replacement APIs that we discussed last time, > such a driver might still want its own domain v.s. default_domain, > for pgsize or other use? If a driver allocates its own domain and attaches it then it should be able to track it and not need to ask the iommu subsystem to give it back to them :) Jason