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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?EGbjWwi9J/EujTfH7gLteUl8OJUc2ZKwZhteR3KMr5I+iHWaAtvbaTlbpyHL?= =?us-ascii?Q?PH0O1Q9YeSY8BRid3o1WyBJoFTtI69z4UzENsgd0oOnnkPMXsOGBO+iWZTir?= =?us-ascii?Q?4dNLAs6nMtd50thh8hQ8bNdGykJOkO8nWOk+yvFdaiiRPUYXnWZuViXIJfQb?= =?us-ascii?Q?xvqaen7Z40sEP5BiE6j4qX5E1kB3HZorjxhk4ziplwwRFIu9m8QPlBOtdgiL?= =?us-ascii?Q?FguDONZ4TmKmfx7XrJQgPZsn5+VxcnyiHmjRkGt45Uv1IoIR27WzzMti7HaU?= =?us-ascii?Q?JI5Cbiv6CyV9NerY4y5aLWOQ8KvegE6rHfXPQjlP9xCS1Zpg4xgDD6k9JpnX?= =?us-ascii?Q?nJBrEDkJQganH2UFCgEWTw4wv/Ji7ZDrCvKFJIww52jZ7Evbj53inbqvbSmE?= =?us-ascii?Q?rPh/VNKwcBkrSaT770ZWvFS7is7P3CeCTjNd61pQmTDfU4unwt6wwZvLst8c?= =?us-ascii?Q?U/tO/X5pOT/IXT25LJAXfjLlKFGz/ljOCDAoiCWvO+MNJDYz4MiPEfCTmd0d?= =?us-ascii?Q?WmWJbClXqjhkqo6GYcd4rCzNCsPgRrNzD9vJGQ9T0IvdZ6Sn+rfU0s4qBKuF?= =?us-ascii?Q?FAcuptDbqZxTbE8TI2ANsJlla3rNlmU76HUe+Ebcl8tSuc6wynM5A7K23gTQ?= =?us-ascii?Q?bdus5hFaZ5B6/JwJnpjPVg2fmPGq2zkDXkTeSxqr1lrXA2GU/0TLTvA08lIj?= =?us-ascii?Q?DA+D6BUg6J1MUATp4EqdTua6tZIrXCJp3c7iHVk0pFuYszk+vtqSnxAn6qWa?= =?us-ascii?Q?BEnCk2Q3m1uN98VdsfIFcJjAPWBXRl7ifKHykHyhhYA2CrjVVQSk7QM+24OE?= =?us-ascii?Q?AoFnBWIwIR/wSHS2jffsPJUX+nfnM4f2rii3jT97GlEBgDj//F5IBYhxK/aL?= =?us-ascii?Q?BHIZW4OnhG+N235cdX3AfZCTHJi1RisgHWR7thFvCcM2/EJ+fk9LbffUiSLa?= =?us-ascii?Q?dLUYut1DyYjrY/4FeNULq9icpVSV28GvB8koK8g0B3fdvF9EYLMaviyVeQrl?= =?us-ascii?Q?tk0HmVd5MgfyIMf5tfIwn9iypNVA6HNwHCH7BHCI6wFiuI31z0i2Vt83fUAz?= =?us-ascii?Q?FqHcx1PqJzk4JgCC0X0sk2tB3+/fiodklzXazMuZ1Ld4RlYB/AfSm4Zg5M6Q?= =?us-ascii?Q?uc5eEgUFdcF4p5/hisWKuPUYLh6SdvRk0W5xCPsqRMc7wIcoHFey37Sk9OLy?= =?us-ascii?Q?PhWuiYr+5H6S9tRq8Dd3A7U/x5phWgqphnP1hpN+br4a7QEPZ+BMkVvLjST1?= =?us-ascii?Q?AtIMrCJQ3lezs0+wiinOqq8Ol7uOtl0AA5P0W66y+No9qkjdLD3ONIIfuKy4?= =?us-ascii?Q?EFFI9FOMYarWl4C04h7zvoyDLCzHnqgBymdMd7CUnpVzJk6bCHfVS3K3tyJz?= =?us-ascii?Q?lmmXU6/CJ1SYAzLPcSnDhq9w0gYUlEv3zKMQWXyKEZdR58hNCGi5fKyrVdiB?= =?us-ascii?Q?GgBrh7waSts9XE0XJjT42ch+2LSEeyhbdUvHYfwVaAYSjxzBJgc/dgyB0uyu?= =?us-ascii?Q?1scB8qOoqHi+EgpC4FkEm5T30wmqAdkZLn7lxTc1LiRa9EpYeSQRbs/dQD+r?= =?us-ascii?Q?UA24+2LOgWhjtedYn2TtSGvLT5lPnsVvPs58KISg8kK1iulC0x1O3DEv2tDe?= =?us-ascii?Q?PXobubbOZYmzWvSVFm5zb0GssqKKnpqnGi7zdQAMVkzSwrnanBozia+ioop1?= =?us-ascii?Q?PuSKEhPYTLvTRNgByDWhrVlxhuyzEi5JhBzbTYuHWRk7nExZ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5eba83bb-f57e-489b-d0f2-08deaab6d8db X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 May 2026 14:59:03.4189 (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: T7k7cF9UcmrPle3n47bDyIx2SkhiCvsXXwZ0F3G8LfVO/0tlqh8SPkO/Ynous8Mw X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB8254 On Tue, May 05, 2026 at 08:50:58AM -0600, Alex Williamson wrote: > On Tue, 5 May 2026 13:49:11 +0300 > Leon Romanovsky wrote: > > > On Mon, May 04, 2026 at 04:40:41AM -0300, Jason Gunthorpe wrote: > > > On Fri, May 01, 2026 at 04:19:15PM -0600, Alex Williamson wrote: > > > > > > > Exporting dma-bufs from vfio-pci is a feature, but mmap of MMIO BARs is > > > > a legacy requirement. That legacy requirement now depends on > > > > PCI_P2PDMA, which depends on 64BIT and ZONE_DEVICE. > > > > > > That should be split up now, Leon missed it when he added the new > > > APIs that didn't require ZONE_DEVICE.. > > > > Sorry, what did I miss here? > > VFIO_DMABUF is an optional feature and is enabled only when P2P support is > > available. It does not affect legacy systems where P2P cannot be enabled. > > If we look at the long term view of moving exclusively to cdev/iommufd, > where VFIO_DMABUF becomes the mechanism for implementing P2P DMA > mappings, VFIO_DMABUF may be optional, but it's highly desirable for > legacy compatibility. There's an argument though that providing P2P > compatibility on platforms that support PCI_P2PDMA is probably > sufficient. The whole reason we developed the P2PDMA stuff the way we did was so that all VFIO platforms could use it and get P2P. Thec code is fine, there is a kconfig/kbuild issue that we can't enable P2PDMA without also ZONE_DEVICE and those need to be split up. Once P2PDMA is available on all arches it is no longer a concern.. Jason