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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?tKwDNUb9B1003itgbFSZFfL+ymKJm8MR1mc4UXy4fyHoqp9xDzT3OWnQs2/6?= =?us-ascii?Q?l3qNTo7nD7I/pQFRzqQskB+npXioIsKGshdS3msTpNLyjeDQ9uM9n1iWwBjs?= =?us-ascii?Q?ivM/WnokDBacC+Wcdb5nXlCT2mmCAbquesggUjU/UuBMdnF5bpXT0DTLwPQs?= =?us-ascii?Q?ziYMEwwz1p67koFA8NkzFP7i6M6CsdGoMW+Us5uA3DI+8VkR6hZqSn3O1gAb?= =?us-ascii?Q?janVI1vZGDJhzrcqGYv/Y+qUNjy+VPaWR9ubi7m80iaF3jJpfuhQQMizNNq8?= =?us-ascii?Q?nap+zZ6Gcj9kF/JF/TG5iE+H623QLfx1O/jybmneYJhC2c6uskJc0ndLEA+b?= =?us-ascii?Q?ojhUYf6W1I4KDrGbWuPxRpgAyXXbnO5rRABFAv71Fe/EdPuUe13z+A6jOjSQ?= =?us-ascii?Q?K2+laJsebLJAMptVtxBrf1K2p8c9+Y656h/Krxm5McryWDJ4lt3rhaOgotr1?= =?us-ascii?Q?cBeUVedj4v623c4Nlh3OVLb678E4Vd02EyXJyStAHBWnYFG7iU8d2S3goOEq?= =?us-ascii?Q?b66MJ90mtWQj2Xc1vjpOyFgeF82ETQRZhVInApnobvHSF9tYDTacWcXnWrkh?= =?us-ascii?Q?q+g1ONW7Tutq0em55j+miaA1ejljQOs1L64Zv60/T2/SseTE7P1a47JYNreF?= =?us-ascii?Q?7ARZfvg8x0w5gAWgOFvkutvzJae0mH5joSomlQAvYdTBX1AcBJcmv9lINzFM?= =?us-ascii?Q?yC2pSvH5hPn0jl2uhLU5/qV3j3aZ6u5Yf14A7r5s/Kz8tKLG0yyB+emeKBwN?= =?us-ascii?Q?np/2LprgWgnnbYkP5VvnUqsqCNoOzpi3rcbgExHvFhAw6Y+vGGkzZF5q9omq?= =?us-ascii?Q?j+x8P1tRJgYCCxEaYUzDZxz3wyZOMp6sUu/KGEGyoFtpA/AlUVVGQIgv6uVg?= =?us-ascii?Q?M2f5P2NCDoGIg6JVxp7iRvhnQHoyIYof0s53zJaivKHanWyerPmZNAD/2JCW?= =?us-ascii?Q?QqwhDjJxXAbugpvOvF67cVkKDiDyUpDNbm91XqT+d0HTAueA2dxLGWT+5vcP?= =?us-ascii?Q?1Ga1wO1dwtQtRcQhH2hrCxsNf2hYgzoeIxeZTos3BU4XNUD/gdb4n8zBnNUT?= =?us-ascii?Q?y2WQYoL0ZhF3YwMUHswfsoTWD05pD9NtSp8yHogGELjsPoP3jx5T2OLsTFnT?= =?us-ascii?Q?Zzc6deR/y9w36SoeUIasxLt65869kVygOd26JyZfqvlYliAMxfFFm94wNzNL?= =?us-ascii?Q?ZTY7w1Pe6TUzr3zMPBMAFObUDbpDVJAw16NPgVML8M56bMx4T3LTXKLyLn0F?= =?us-ascii?Q?BxUOpG4LAroyXjwL1HRhftqgnaiHQQNF0ZclUvSMm6ZtM6501K4TjHf6xZpk?= =?us-ascii?Q?FviWbQxaqCtlbGKj+BZc6r9sZX1MCNDYMFPfu7Hv+xE5rSNT7IBzWGHqZbdF?= =?us-ascii?Q?F7Rnpa3XKfK5kamExqc0XC7+7boFy2ZZmjrPT41Y7wghEKDziABXJOJmNyUp?= =?us-ascii?Q?mkF/0ULnTBcJ+8gc2RoZDgktLUJB5dRrnN8+Iej/X+MfrMXJOjw3t2jaZIGk?= =?us-ascii?Q?ZTz/Ti5yT19o4R3dzzrgMFFx8e6uOeuf7089U9kx6Q2EmkxSzBBrLW51SHzg?= =?us-ascii?Q?41No9LAGUBK/bGumP8FlxpT4Qh+bDyDCHPgYmfWy/ERYwcgKmyI7AQUkVFmm?= =?us-ascii?Q?ck0OMRsyIpBVWy3AOLjEK8S3nHExNKGcaQ3/vi1V9lUZo/rUHNMbt/YNIiCn?= =?us-ascii?Q?QyJKGzd5lVcv3iJi/E/noY5cstZJfJt6vjC7m2dRO0o8H0q4?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a789338d-ae5a-472c-5694-08de6036ba40 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Jan 2026 19:35:30.4604 (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: qG9zcBSlu4VsJu860WR0WXYJDrkFBqeWs5/xKS+SF2F2/JZm0xXzqlK2JxlQIbAY X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6634 On Mon, Dec 01, 2025 at 09:30:04AM -0800, Jacob Pan wrote: > VFIO's unsafe_noiommu_mode has long provided a way for userspace drivers > to operate on platforms lacking a hardware IOMMU. Today, IOMMUFD also > supports No-IOMMU mode for group based devices under vfio_compat mode. > However, IOMMUFD's native character device (cdev) does not yet implement > No-IOMMU mode, which is the purpose of this patch. In summary, we have: I tried to build this without the fake iommu driver and it worked out OK: https://github.com/jgunthorpe/linux/commits/iommufd_noiommu/ Needs a little more checking than I might have done, but can you take that and try for a submission? Thanks, Jason