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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?dVwmFDil+D5xpY6yzP45s/3HQSz5CkfDIBsAXpt1GE/5LyrmJDXE+J+1JME4?= =?us-ascii?Q?IU4ynkIYH4j/+XGWdxXKmDVWuJpndn/ZX3popVLdouu6G+JVFZdV5oviI4cv?= =?us-ascii?Q?diHmefEzIj7H3YqeBcV6hXztq8/5GTbcyN7tGQteB79f934PbcZrQz1CycZG?= =?us-ascii?Q?Yd484vRtiSyRO7KdlsvoLe7np73e/x+zr3LAcDlOp2HDmL7FqTrkzRhxfRVA?= =?us-ascii?Q?KoVVM58FNtPR++pVE5Zhba+w6tVZinZN9llf/zGl5pPMg8at1VSk2RXwQrnb?= =?us-ascii?Q?c1RPiKCCasZ3T6CKRq/YRq6BWX1BK63VK9eJFk3yGfhBV2x8tocLP5PnuS7+?= =?us-ascii?Q?TLVV8JpB7GCgcsKGx8JIBW5PYrmOhHMrWMlE8TwPHfuzX3+v3ECq7+LQOMLL?= =?us-ascii?Q?VR2BezLHCzxyaTbKq8gZPoDj8W8YsP2SX2kOQoiBWaf+r6HsOn+tUCLy6ApN?= =?us-ascii?Q?JkYhUZ0RKJfuqF/k1c2PezlFyUjbEzW4ZvVqlg4Z8dXKJ2S1+oewqe5gXDk+?= =?us-ascii?Q?VT3BREcHgmuvuLjHMfkVGR6n/m9AN4LV0/cKvZMTmQ9RS5ikCH76FMFxi/az?= =?us-ascii?Q?q/ylPUrk5BymCBvaicOu+SO2zh5v4EIrB+Q3PzQaGF/Kxk7elnTfRkJxIywx?= =?us-ascii?Q?GZazpuPrQpuZm8R2JwgZ2izCnd7AerMCVZgMgkUTcoDvQ8Ev3q4f5FBMMdq7?= =?us-ascii?Q?/1WKwszUeOLmdDoZiQdCe2v5XqlZzNeFF0Q4VxUtPzBCNV/8aTeHFyW9YBX0?= =?us-ascii?Q?/2VIxFUtCEhI/5MFLmtuME/BAXI3ZtFLNDkCTcIx0aTNe65yCoxQow/atRVz?= =?us-ascii?Q?e1HD8PvlDwPO7y88yT4+OYm372zehzcgtvVPQX+9hHr+7G4aR6LoursjvdeC?= =?us-ascii?Q?HsZDSP51NVZH8RQq7nIO1DZQpsM3QqrQwz2nIn6RmChCxPuMOWGr9lNyTjXP?= =?us-ascii?Q?aQ6HjZ68pBkRmPkbwb+bz1A2ckUh+GrnGhlzX/99RQki3wiPWJl5rwlnYCJY?= =?us-ascii?Q?dZmuaa9O0Bm+ZeVdkkluAacDiXN0bSkNhjz5HaoFy/wZb8cWo4YMx9LODaNq?= =?us-ascii?Q?Xi4l/ig0u+zQP9KZYATi3d9k8kdbHIk4OlNpQv6RqcHNCHpjHb+241/dc03l?= =?us-ascii?Q?2PLUqtu7y/Tq2StBzvY0s36WG6iVZn42RH5/XQ58AkkDxnM1+//FR38u6505?= =?us-ascii?Q?EqeMO4avtwCxsi0VAzCr/1KvKn2GTxPL/mkddPo13z6+7LsORAAwBcmL5+1n?= =?us-ascii?Q?xI/GbHzQz9Os/pXc3KtlWPdrODdf+MK0TWib2po7NStlpMsGzHUC18ERCQWX?= =?us-ascii?Q?/bilgOahvt9AfzeTWI8AWi7f6sM17fDRtrTLZKJz7wYSFrTFF9DjTvm5LZFf?= =?us-ascii?Q?ddRFrOjbNVtvusEHFTJhzYNQLo2IAqPSrS6kTWU+l58/hcK7oweSBLcj1b4M?= =?us-ascii?Q?Gn5YXnoO7Dm1G0Xc5Ip7bdmFRXB4kHHx6VRTFSLt9uq79EM6vWTsrZu2TUqn?= =?us-ascii?Q?tkRjz6CoFs+hwb+/RfRDjD1Qs5NKT8jae0m1/oJHyYh1vWd640itwXzCwsDm?= =?us-ascii?Q?iTmfp5GktfFv3gOLBh3/lPSPZqFd2ief8U/BilawA5HE5LnpEmSlvGxEnaMf?= =?us-ascii?Q?P0srVi3VrqjOML2Zf7VHIVNdd2EimGJIwjaeClSvp47jbykGBWKzDlOicIKh?= =?us-ascii?Q?CDKwhIWqB/5sW77Sar+NWL1vJi7W4wYeCxWeQ2B914o0Nfl2?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a4ec01ac-6ae7-4d6a-ff39-08deafaf7337 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 May 2026 22:48:42.2994 (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: 2Q5zmiKIXDC058cnpcfzI8Bisrye2BTbX9tIEhtjXqESrfYZJ7J1JueOaKm5zceB X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR12MB6293 On Sat, May 09, 2026 at 01:31:56PM +0800, Xu Yilun wrote: > > Would you be open to an in-between? The exporter and importer both > > have information that should not leak into each other's drivers. > > > > What if the dmabuf mapping type core code was the only thing that had > > access to *BOTH*? The exporter provides the address data, the importer > > provides the iommu_domain. The core code, and only the core code, has > > both and does the required operation? > > I think that may not work for KVM. On IOMMU side, IOMMUFD acts as the > address space (iova) manager and dma_api/IOMMU driver acts as the > actual page table mapper. But for KVM, it is both. KVM doesn't allow > another component to provide an unknown address space (GPA space) and > say "map it", so doesn't expose to other components about "KVM domain". > > Even if we expose "KVM domain", KVM still acts as the importer and the > mapper, is it wierd to say we trust KVM-the-mapper, but don't trust > KVM-the-as-manager? > > Is it also wierd that we trust IOMMU-the-mapper, but don't trust > IOMMUFD-the-as-manager? There are more IOMMU drivers than IOMMUFD... Yeah, it doesn't work well for kvm, and yes it is really weird and worse that phys in every way.. Jason