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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6uvSgHoCoTTaUwDjngNrZAh2hInzzrEVT9kIixcj4rvFA+zgMpL1y3qoCefE?= =?us-ascii?Q?Mch0w4TG3+NydSkwDNf9f/nCvk8ZlNfaiaNM5t1XrQDHtSA3iHTQ/Kl6RH+X?= =?us-ascii?Q?u0PIaXqB3Rv9PSFKb2z7N/Bys8HMh4ZpnVlZEDOZfolG43JZKHBTtN89459h?= =?us-ascii?Q?ml6n4T0DoNzhdiWOUZ8y+rnD/25NRsY7RElPtqk7hAEU0/PwbpNJfRfszqiI?= =?us-ascii?Q?ALBtIoNaU9ylJ8GCHO/vZi+GVURYdJzraYKVDN0w0Iuap/fXAlzoaWMI3EM9?= =?us-ascii?Q?79Knp0r+7LGS4J64+j1fy7iunhYmP0xqyfhh5C4W30ZkeZAALIB8F3WfEpdh?= =?us-ascii?Q?T5NNZcyTzYw3QnZuEwZtUvst0lFzgRhjoENx9ERanEEF/i4e6ErsLcYMaecZ?= =?us-ascii?Q?q20MZxcAO0L3+mr5VwHRglAerSEztUk9pWlHOdn9DZjOFXZTzbCt1B/m+cUb?= =?us-ascii?Q?a0OZLvflt04chcd4aS9iKrtNDp8fttGooBb1dXwNUalWaLxsUR9fHwdaUEjr?= =?us-ascii?Q?EV64U01MIkOQc0+Kx4kG3YKY/SKWSr8HTur20ujyaGqkUJffM7CcmRgKurRP?= =?us-ascii?Q?M36P6Y2qJga75jrwr9MJ+itODtgs5KiA4M9adooklmUOZVaD1nt5moOk/prH?= =?us-ascii?Q?WO7yPw5Hr8iEu9xaV+K3ZyZ4V9agTu0ZaL07wvudzX8L8T7Kh06RCjIKF03d?= =?us-ascii?Q?2Kt38XSaavU8rmHze+aLAi/NRPaLWJas/h1j3ok5QctJgQZ7eWgJJ7wsV2hO?= =?us-ascii?Q?sdPU4mqJxtJbakZ/tup01R0dLV97fqBEPmuKI4jLwBbpHqJtb/sZPP3vOydp?= =?us-ascii?Q?IPWUX51/bxpftFjBYd8hA2gPHJ8G1niojMKesDwqoPrUFLibtSeYj8PKkEHF?= =?us-ascii?Q?Qp/eKkkOw8apAwKnErphQ0LD0KFXJj7yzfuNaFl98jYPrhZy+iyRonvOCJL2?= =?us-ascii?Q?qwO63KnNMpyU6TxooyK+KPUg+BUUQilN1HA2E7rEZCfn+t9I2iHOxXJmiYo+?= =?us-ascii?Q?9FMLg8K/AfOhUT5ym404Xx5XJxmiLB/eTd9+R8SPzNG5MVxChXmCl35FsK7v?= =?us-ascii?Q?aIkINyrwKoaaeFazYqJFKYUbeAmCIYCXCL0oMTC4Q59a+i7EIlXqO4fVKRPA?= =?us-ascii?Q?GB7JMy39yZFdAFKhCGxaVC2VFS+lLmht5u2poVe0gAfF+9YrN233wiNB9Img?= =?us-ascii?Q?alqx5XLM9+3aPs4f0RX2+LMmrVA5kpaa0mOkw4+9/ZUcFGeSf+9dO6ApnIgi?= =?us-ascii?Q?gn6xWDZp2wF7YiOCNYCKCHqJ1nTNlhPtS7v/SWwrVZFOuddH62S32zDwofHP?= =?us-ascii?Q?ZmQK2K/m5e6UVP+YlorCcCPKhYcw0/5Q8SyRJkusO5op1MlWRAeQa6IvEJ/F?= =?us-ascii?Q?eS7MrZMmahPkMpVqwft07mCs0zt9ZB8M/9a8ip5GItYjPXzypxkj8/6a7aA4?= =?us-ascii?Q?P/k6Ba3nzv4A2N+9i/rUr7npJk1bJGfY0J93JarX4GeDBmwpUMUfTuK+J9c8?= =?us-ascii?Q?+dt1ma7o5Dy0gznfQO4A79bQZ5GpEkSznpuQGiQJ0ZfJVeX3BnFiYrZbB1EB?= =?us-ascii?Q?b1ghuPSC9RKwZufFxlMuiKlBu99TXWrYBhQHZVE9eKIA5IDbUOjAN4TDktO6?= =?us-ascii?Q?tjY4eBxwUyG2Ja1IB3aQvt3WulOAmMtVJv8Uiue1Ar3p+l4jtf4bP7UKMo64?= =?us-ascii?Q?Mi9B6RqA2ao8VbTEV/CmS96F9bJve23tlLUhqWKAKRiURMVgGDqV30YMU2DZ?= =?us-ascii?Q?kl90BI+QeQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b65416b9-cfd5-4889-16a1-08def7b106db X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Aug 2026 14:01:23.1394 (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: nQoolz9kIY/Li+P2CfoPDAOU6VMMC4+6xmtqHAGEgokiC78Z3rhTLjcFJIt+Pa1B X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB6168 On Tue, Aug 11, 2026 at 02:45:59PM +0100, Matt Evans wrote: > So we can just do this: > > - VFIO exports DMABUF internally for mmap() > - It attempts to get a provider for the export, but if > CONFIG_PCI_P2PDMA=n then provider is NULL. > - The DMABUF works fine for CPU access through the VMA > - If someone were to fish out the DMABUF from the VMA/fds then it cannot > be imported unless the provider is valid (dma_buf_map_attachment() > returns -EINVAL) > - Drop the P2PDMA changes entirely > > IOW, when CONFIG_PCI_P2PDMA=n you obviously don't get to import DMABUFs > into another driver for P2P, so the provider is unused ... and when > P2PDMA is supported, the VFIO BAR VMA's DMABUF has a provider, so could > be imported for P2P. The struct vfio_pci_dma_buf only needs to have a > valid provider if the DMABUF could possibly be imported of course. > > The behaviour of pcim_p2pdma_provider() is unchanged, as are any other > consumers such as mlx5. > > This is way simpler. I will drop these first two P2PDMA refactor > patches from this series. Sorry for the churn and time spent on these; > though a cleanup/refactor could have merit separately it sounds like > there's discussion needed on exactly what that goal should be. We are going to want to do this eventually because not being able to import a dmabuf means vfio won't work with iommufd - and there are still a bunch of architectures that will be impacted by that coupling. I'm fine with you punting on this issue though Jason