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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?5oxzG6eUKTuoc7/7KzyEtliNERPkORr/nT6gQEtPN0kGnKSinrLzg2AeAcm4?= =?us-ascii?Q?zqdReVmdP4ZExKZANQwk+zbuZM2qbd3SUk+cX9Fjw0Lqt7iKMsI5jZDYmCcY?= =?us-ascii?Q?Az44VObygF6B00hYZCaTFSQXv4EAMk5wnI1Fe6A4kDtaXWNjbp63YOdbkkDE?= =?us-ascii?Q?hbn3GgLLS3oRBBInb5KRSqMAmtsYp83ylGhgS9QRsziJ/lBXOGhp5FqvI1Hs?= =?us-ascii?Q?Kai3dp6o0wNyZ0xixz3yibkPcbXf7yLvRMvolc4ZY4l8X+Yr2+kt5qMmcu/t?= =?us-ascii?Q?wmvJIRSRzZOVjBWSedu0KcK4Brt4k6A3VgCCJSqmq92Gc4mo0eniUwcxwcvg?= =?us-ascii?Q?jI/Ij8rRMSIGupHLEBTF17gUrP7Y2ffMCcyccxlxbV9a66DUWjhcMa8NR8iZ?= =?us-ascii?Q?zLWNtij52jPGP1BVHHSkpXQFrWBvbaIlnZ/bsSjX5KwxbVLsrq0N9k/Dt7ZD?= =?us-ascii?Q?x9ea5OHgvdnTd2HN6z5TB42QNFj3x5hBX8oC1w3gt/y/KLLlrcDwvS2i0xHh?= =?us-ascii?Q?Mjvpe9qewOhCNgvXS2NqEY4nIMekzi3wA9uCulN8FP1wXnVx/uyUyZQUyCnj?= =?us-ascii?Q?PEyl/CxjKl3MhlLiqSIeX69+sTf3D8CS7KrtUvxG4NJv9e2rnO0DjO7NilRJ?= =?us-ascii?Q?T7a1xcgcOKDtqctmWP6Wp5x47ZxSUfq5VcjbTCPJsKUU7uk6/VxQBZDAwO+e?= =?us-ascii?Q?tZaNTVuhAQ/hOTanR1QWp4LlvgEywMDBUsv4N1N77rxsxX4Tw98BT2BfPVdf?= =?us-ascii?Q?LhccCOBEQpEM/PPP2SArefg3GX28dgu9arebTxDGD8EigNaZppI4AEzCkoI2?= =?us-ascii?Q?Dg1rDx1O8E5Epjdca2BIROzgrkeYmCBhHX9ntVfqzkfOmjFiUwCRfyflbY0J?= =?us-ascii?Q?eTS1gztNNp78qHKo/+K6mh1YLlPOB64Wos72ntwXr34g7kSURiSvDyJfXWjM?= =?us-ascii?Q?Sdi0gWTxDD+BKj3uwk6/hX2NGYMHdU2WUp1/v9TYbRTpX54MyKt64SlhC4qu?= =?us-ascii?Q?/1ORD28HNlty7lXHijy1CHCr5Lhn5VER9FOPXKpWB7gSLg+MQBTQrhT+Cg2e?= =?us-ascii?Q?Yzs9rn12Oj/taSbBXpFf+NLQVvTEAWm1fMtE/LdmnTontdNWtQcjt0G24d7N?= =?us-ascii?Q?pLDtdz9KNvBt75X+CZ+iRV2yJn0TQ48UOrRoUke5Iw7olGt1fAbtkhVBcWke?= =?us-ascii?Q?aLPCadepErFKoGPIVpNtyCWdzooO14pV+ywLJF3BiYiYhhxwT0zpUCYeOqWw?= =?us-ascii?Q?9oUrcacHEHD9lKQ7ttTj5oi/fflisigRmtP1OQYp19GyquQeB35K8Pcb5KT2?= =?us-ascii?Q?qIQSHLNMS7K74u1WvwP+EAX5r79OxutYviw9MTk1pCP+v+juO1Nbf7n7uOPs?= =?us-ascii?Q?qEN4xUs1LY5AVAgb3/rrBS6XMrSmX5Ofxkz5Ezy3FUwso5xcpkqZAqhz4lr6?= =?us-ascii?Q?LusUnkZEW8dtxBEd/vMqXWZZuDPM2Ab1HSSZnvtQtbqutoCNwWQ9qbvYAlRD?= =?us-ascii?Q?gJKwbuIolYeiYEO7xEQuDqr5cPHDQ6JHYP2bR5aaljZEdYhiChlVNR+wUeOP?= =?us-ascii?Q?AVslKYAq9uNpY1GGKy6pVZLRKW9sRyoSct9DnSTWF+XnoTvt6uzYmVnj61uE?= =?us-ascii?Q?OiyxulWtYJ8U1TWU2E4bGK7KLtUyXa4sbWqrDAPLq3Q5uIEGGk2nPzl5/d6p?= =?us-ascii?Q?e9cJJ3F9rfdI3YN6VNnRuyQm8VElIFYS4DHycfTx2iH6zJHY1CQzb74EaAe9?= =?us-ascii?Q?h7/hBv+ehQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0813e551-ee4c-45a3-dd34-08def28a4f5f X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Aug 2026 00:41:38.6052 (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: 60sgLsxIJKcdUm9hFCgb95qWbN64mdhekXBcZfZiyQBJwjzRpaSvkSgvn3llr19F X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5969 On Mon, Aug 03, 2026 at 07:22:06PM +0100, Matt Evans wrote: > The second problem is this isn't just a limitation to not do an mmap() > with offset approaching 1TB, because you could run into trouble just > mapping, say, a 2TB BAR and then splitting it by unmapping a hole in the > middle: the second VMA now has a huge offset. > > It seems a proper fix is easy though: > > unsigned long vma_off = (vma->vm_pgoff - priv->vma_pgoff_adjust) << > PAGE_SHIFT; /* No masking! */ > > Then in vfio_pci_core_mmap_prep_dmabuf(), > > priv->vma_pgoff_adjust = vma->vm_pgoff; > > I.e., if vma_pgoff_adjust just includes the region index up high, it > cancels out the (same) index in the vm_pgoff. Thus regular mmap should > work (up to the 1TB offset), and DMABUF VMAs can have arbitrarily large > offsets. This is what I was expecting when I pointed at this stuff in the first place :) Jason