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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?wvH+h9sEGxVzQEnUy9PMqtWLSATdT2bltIY1F4wxk77ddwR2hNm3YqIqWKyJ?= =?us-ascii?Q?0kiT5CSfisUxHz0he3Ls0FNd4gsvy1vYAGMR7wv9XAHeFfEhmA1Hy8xBpgfc?= =?us-ascii?Q?CeVQp3MJSXujY6S/6KjxsxNN8FrszCmWUSyg+HN4+tmbOS+pVO4gCmfgPeRp?= =?us-ascii?Q?R3oLX33LU4l4xqitz4eQ9qyAyhC7ed/ybXIzDlxg3ZEqBxiHJA3MrONirZnG?= =?us-ascii?Q?fD37etUy09OAZRAltCjVKSwKWTaE6H0jQcYsQ+5F1dqbwxsYPpTLa56Uyhay?= =?us-ascii?Q?6HJLGJ3nRBQI4Wyly7o0mmlIVpdXOOOO4tqpl5bgEpanXWQ0jogbCtnd1bl6?= =?us-ascii?Q?Wf8wEFkUSqk3jH78YAeJ+sz6PIFpwdGtV49ljXpczrYS4aybuman/MaJ5GCu?= =?us-ascii?Q?xDQ6P16MAkWtLTl0BLd9CgRBSoKYAjWIm/sjRIxHGaPGLu/Ny1xZssx3qRW8?= =?us-ascii?Q?1UsemdXhqCi4EJSSNY/c+owRbCNYoJXcw5YITM+9Nmwe1fieB92yRqFQlPV1?= =?us-ascii?Q?xOYF7i1c3yDNS4NBVOpZliWhFl7+vdaeKEa8dgMiV91M1wK8Ua9iaX1aP5iB?= =?us-ascii?Q?0JrmMD5kSGHssr2P0ww73kEEqAuMh5212+RjxK5g8Vx0K/usKFt06aLUiHzx?= =?us-ascii?Q?2AxLAtr4x2SBOJHuzEaJFB+RxyFCHMpCo9aPlOxmKm49T8d3jya3SflNpxR3?= =?us-ascii?Q?Hzc8c4dqJuMeZObCXwA2yxRAWiLr5k3NHITvQI4WW9b31fpS04A7NY6Kd6PD?= =?us-ascii?Q?UpofJoOF3xMwlul0Ef7KL/li0NCcFpI88Dejwp3kV705nugUnfljxtmyQrGi?= =?us-ascii?Q?qHQvhGyOhX/S9AflTnx8BuxT97VWChuzl81DvefiAJt6EB4E/3Hpj3VEFx23?= =?us-ascii?Q?WgQliMVT0hfzOTndcB8rQ+X0xCIg5c4XL+tSvZCIL1LwQjjvJF9/0E5FG94V?= =?us-ascii?Q?hqxMjp/hhw20y+dQdDkke0jDnDZfH0tJUWYubwgBI4XM+Y+YN9HBgHnQx5Nj?= =?us-ascii?Q?IRqc7RFXaCiuUkT9dM+1ETT1mHF2MK3/Pr5yeNbVs3GLn3olp7bSSlhpOVrc?= =?us-ascii?Q?A/AGvYtRhAGCQnGBZGrgLy7tqNgPIzXCXD3IlmAFeBH5PBUU4kIfo9m4vwdW?= =?us-ascii?Q?fBKCQmMtFza2GCltsV7XSFqpL92ukqAEZcAaE+S/fKYm9YI3rCGrLR28SEG1?= =?us-ascii?Q?I0/Cfm0UVlMHUo2oqdxZ6c6yWA6FTYAasmde8R/9AeB/17v6qSPU6ljSFgqc?= =?us-ascii?Q?azgs7gWy+PmFlBYNMKMM8nLdV0sVVUlyNhIfoZYZVr3JhTK78UqBn2mZTiNx?= =?us-ascii?Q?nsBhMNXKaei69iB0p+lXpwnRgUGJzolEq8Ff/rSLCR668A1Ia1uKlmVZwzGo?= =?us-ascii?Q?3miEQqNwXzDBqGjAZ/3desJsJDbmc91gO1K0aqBMoUt6GKGWQgzebcoTVZw0?= =?us-ascii?Q?pVsl/Emf8W4tShIdo146xKZLYbRIkOqL5QAezBUquRswv41/suLqaL4Gw3As?= =?us-ascii?Q?hbEbPUWlXzK7bTjZUY2onnMPaFpxD2ZbvmBjnBlk8s/85glTTcZ+V5stiibk?= =?us-ascii?Q?3H12B1+NT2FeJOyg6LjP/TwgajA92WPxNmfVK5OjehLDEw2j7hfc3dJmLNDv?= =?us-ascii?Q?xY7/FDMZI/3nG8/pEAp1YpR6gwsKKfucUJCWWxN4ZJ2MNxW/VCszX+Koe9xc?= =?us-ascii?Q?NlwzNTit9HetBJPQkLO2YFQgm71Dkmijic1wc7nfwQRDLiYQ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5c1ff189-dbec-443b-9628-08df2613a9b2 X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Oct 2026 14:43:20.3977 (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: qzXEd/gUoEsZUvqa7XwV8tugZN2Bt6Reo9yjYPaCXa8IdvlCUBp//hoqG4EFVYXY X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB8207 On Fri, Oct 09, 2026 at 02:21:13AM +0200, Karl Mehltretter wrote: > DMA-BUF attachments provide DMA addresses, not CPU-side pages. > iommu_map_sgtable() needs those pages, so private-domain importers such > as Rockchip cannot use it with strict DMABUF_DEBUG. > > Add an iommu-dma helper to map a live attachment into another domain by > translating through the device's default DMA domain. Roll back target > mappings on error. This still recovers physical addresses > internally. Absolutely not. You cannot recover the phys_addr's from a DMABUF expoter by using iommu_iova_to_phys(). Christian is adamant that drivers must not use physical addresses, and I will not agree to any hacks like this to try to end-run around his prohibition by abusing iommu subsystem. NAKed-by: Jason Gunthorpe If you want to keep the domain in the rockchip driver you have to fix DMABUF to allow an importer to use an iommu domain safely. It *must not* be done with a scatterlist interface, sorry, I know that is alot of work but Alistair is going to take a serious stab at it. Many users want this, not just rockchip. So help with the work to allow iommufd to do this and you will get it for free. Jason