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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?WMGLzHUUEXetKPbaU3+QdYnCi2OtYAtYJh2GV6s3bSQlKKU20cIi12ppZ+nO?= =?us-ascii?Q?0OwUow8720nrrAi8/lj6zvS4xfp9obZ3yN36Y8Bxb8JOomZWzhct4iMikYq9?= =?us-ascii?Q?6f3HOev+sBEtMfWRU4BPFs2fvIqCcGkR3SHkMf4PKIejXOk+66pVOTgMy78H?= =?us-ascii?Q?EhwXWnomIMl0IxVAbfPDJkBiM22XAIOTRWCY8MvgidVzS/GqdB+/KO40Ip7U?= =?us-ascii?Q?E1JmI+KM3+oO2egP9F1dDogDpH73DNNrkCzLeqCZnjXQRWmS0m7alFxJSYUK?= =?us-ascii?Q?C26EKU97Ki2rdF+UB9r2doPQiLUJ8Fscm7a4MlO2BG9ZOevlxAMSJTEGqkat?= =?us-ascii?Q?oRkeJSKaNzpzdRJ6rAs6q+Un1OrGlO10iUW0zjs1NwHN/gv4HctRYXoQrt2q?= =?us-ascii?Q?P9FqQYfXwHyUjTNpdA5B2eCIAPtxXwGA7Wi8RQndSzd++S85WmaHLf1GXz26?= =?us-ascii?Q?32S5aAtGe98NyT247DoX+GKfkjW6ucP7Nn/k9GNk4SYSrcGD/51C+hO4RMIs?= =?us-ascii?Q?Hmlv5qLk0CekFzkKD1hV0y7Ny/d8/V8l3zX8owym0tNHhADUe2iGX+HGQoeg?= =?us-ascii?Q?+Y3L/DYysZhQNOFKMc3s/jFGjVxP9mcvCyvqJAKiC3UgWsQsSdLE4MSOmOqq?= =?us-ascii?Q?t5y1g4eYb+adLFDqGfoxuucHDyLW3H1NvhOSnzHXTxHglxPsUdUMo1tHBz+1?= =?us-ascii?Q?fvOfVUzaRhH9lqIqnOEHepKSxi/avx5sdwCLXBt9Kh8+ABtkqIaldjmNUtXj?= =?us-ascii?Q?67vEeMrl/aDypGpqCiUR8gM+o5nd4bv8oR2g1jbHFSn1/fPwA1wkD0X3gTv4?= =?us-ascii?Q?RGvAAE9bPzWdVwVEMwvaD08qKAan3AZwbH8eCD8uYepl3Y5HJwvBsenhsxbV?= =?us-ascii?Q?pDIM1jhKowI40GrQ2yKQaMm0pO4k615oFAPI7V8z+ck1y9rBR8pXX086dAWW?= =?us-ascii?Q?uObuxUXseBcCbLq8YDs1/a91NjUbP91x5vtu2OyEjF1C1th1RUEZBsdnI6j/?= =?us-ascii?Q?hjHUa09+Fic2rgJOSGRsRFAUOySHO34JUOPpC3cHnfQToDzhql9h5HE6NLYH?= =?us-ascii?Q?sJL/R/AiQA6MuWDDDooJqgDx1NsA/z/7ataxP875oYi8wtcwB9LzRE6JKQbp?= =?us-ascii?Q?tGVMdcvG+5UDE8SOlZ7HDoF92ZXhsqyrZs2elwf6MFKkcemWtkQaaf1asvJ1?= =?us-ascii?Q?4nBr6+n5NWaY+nhAhyVP3vB19y3GnebOevDuXf7d1os3y87UcZDi6zMrxUR0?= =?us-ascii?Q?YKlX6ZqS5rqnnBw/DM5HvwtGJLz7kP0+Fd0iDMGBHJCfV99vYcNwV5/bZz4V?= =?us-ascii?Q?VES8d5QyhupaBUTRgoj1lCplJxmDiSG6i4fQ5aZ22VRpwCNEzuwH/ojslKSD?= =?us-ascii?Q?AZ4++IzRTfz/LT1zRsl00E9LoVGJNjBpnql1boA4gJkXfV/EFMY5YNV7I37c?= =?us-ascii?Q?3q9qXyR4CpSEetEYxne8dBUMrNDSMHgC319zaNmKix0cCfnmV9vQ8XUGPow1?= =?us-ascii?Q?B4PiX8aDwcqzq5JAbFQUL/mwOQHuRkcgL+TQJeCnV6OEiXJgnHC84V31E5Vx?= =?us-ascii?Q?MVtk0k8LBXFEikyZW+RcekUcIIqeYVLZggnGJmG6JtnyLOPreGfVgMeXU0KX?= =?us-ascii?Q?/HOJZCNzo6VJ7l+JoNaByEvga9DfoZZNqRP6wGOmrYul/iJV8Mg2W27KCW3N?= =?us-ascii?Q?WZzRrLURIa3cX9Uuu5ebD3Kj7efjtrhdMKx4CT88nUL3JdPnpFJEt2ZkbySH?= =?us-ascii?Q?FIOu1TLsdw=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5957665c-a684-498d-042f-08def28a4f58 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Aug 2026 00:41:38.5368 (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: 3wA6o2Pvsu7aUbLPJTCJYQLS39jCah3vh+0kFiNk7nCxfH+d4SEvI+jFcwZwpvIM 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