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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?CcE9pb4GNUKzyEcxareJMEHhTiWiViMT2FrGGjX4qIUyhh18UMBWR2z7WLpJ?= =?us-ascii?Q?Z6umDQ6oJ1KuJgsrdX0Tdh6I0NOuoaH7sHdPPnSKYIKfQ5RK7XX8wEDmr0QC?= =?us-ascii?Q?viQ8jeESBYKzTompV+Ly1KQnk2Grvfx4I0ZY5p8c9eP8pjkWxC/5idWxQO3b?= =?us-ascii?Q?wdhX+q3vRThlIIfdn/P8wt7TFImQlJnGOnCYC4RKcDcSihR65ohcyQOkM4uu?= =?us-ascii?Q?3um+/RxQxnPG2iOXZ6V3UCknrJOiylDHC65FC13IzrAolckYOBiI5Dx6EVsT?= =?us-ascii?Q?JmwYd2RDNyfB73wQdDkjlzgpLg7ymOH8z+LT+2466CjBoL8scZ5RYRg4RPI5?= =?us-ascii?Q?gO5QwHoN+JjPmFp53MeD5nSY2R+hFXPtVq2g0F30P9YuScHTB1BNJzaYPeYv?= =?us-ascii?Q?rkSN7Z3GADZjHhUZjNPZveOSv4VjT9u5B+5Ccot6TsaS4DKkUGPMvx363N3M?= =?us-ascii?Q?sJ3BpIxHanovG1pA2uPOZPCwIaD+SmfV7Z8Jol0EBg672RQjWBoc1aIzOZbq?= =?us-ascii?Q?bH0uFvcy9EZZYlXdfMuME0WPEXQAnUBhkKuGsVWrCN3tJOaZiUYa3u+fhyIm?= =?us-ascii?Q?oBL+Ki0rXj1vZfVRzFCsiKB01FSRcZ8K5nxHF/jvnUAhZum3/jtK/eOFMBrf?= =?us-ascii?Q?UF369SJCHyOH/pDhSjbP2Nn/3JpV8ql3NjH/PYkNecOc1N9EbiK7ZbcfMjDI?= =?us-ascii?Q?gGj/kyhR6XLpZU/VJKsVf+fvCUueaFtbVNYdNwdFtBQLR/TJpf3+senBHcNl?= =?us-ascii?Q?FmwiJKPdnSvhTmQDUiVyiyDL2P3kMxvX0OdNnvAver7xArL81nkliBwYxFf+?= =?us-ascii?Q?RLC+IwIKjNx29i2CZBikkk4PdlzmFpTeHSF5ieZ3ZehD8oRXH5UX7q4xRbyT?= =?us-ascii?Q?HJypMQF4DQ1OUinkFC5/T0Qygaa3IN1ZQ5XfzX5p3gcRtl7qdIcT7d2PKSY7?= =?us-ascii?Q?TXGEwMfLrvrVqD3nDhIBGy/RJivt19uWMWahUCDo/682SsOp5lm5oTnU4VoK?= =?us-ascii?Q?i4iSpTQJiCbBIHlcZvR33SEL/oiYa/2SsPBwqD+/HyKe4ga1Sqzgy6ztHXN3?= =?us-ascii?Q?uKKXYDxukSQCcPsqIPo2oazvcjKbYBUchjX1xjmMPS9of/xT5v0MbL+b1rrn?= =?us-ascii?Q?9cC50MmPxhAzvRhVbA7v9hYXazIxDe+odUR9MGp064MW9GC7QRvMVUtBKYo0?= =?us-ascii?Q?VcbG5BN7cnaigDXuFuQuuP0UPP5ClyTn4XhRRF199Lw5nI2XH/wyk4J88caG?= =?us-ascii?Q?51V7aUqx2aO16uOXehgGS+lT9M1CSQYrx2ba3xCLf9pUjQWiAEtyocG9ddwp?= =?us-ascii?Q?07jd7Or/mK9f/QitUglfFX8DbflOszgqtX6ZoolptuGZQGRV9FOQoGEY6Yhk?= =?us-ascii?Q?glo8slOsmik1HgdJx4/wIDoLLst15DRkuhsh+5IxNIMaCbds4JXIEpnabdz8?= =?us-ascii?Q?5z9QTR1YvaP32797QCKaAXTlRXJ+QJZWSrBR8TbukJ/nvSL76JNWq7su7u1M?= =?us-ascii?Q?gVeTPditKExo0pPKYfn85+T9Olstm6vvr0CIL5SYbRxNCs8fkrROXUd0/9We?= =?us-ascii?Q?Uh1hS+Q1HdYbBQmD7og=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c95c332b-48ad-4414-d860-08dceecb5a9f X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Oct 2024 16:47:14.8287 (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: YUiKxHze+sFMpXfAWEDTo8/fwzM2Iqpb5k92fKoKCk5hUPJ6Pjcyl7IneTy22WaW X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7795 On Thu, Oct 17, 2024 at 10:58:29AM -0400, Peter Xu wrote: > My question was more torwards whether gmemfd could still expose the > possibility to be used in VA forms to other modules that may not support > fd+offsets yet. I keep hearing they don't want to support page pinning on a guestmemfd mapping, so VA based paths could not work. > I think as long as we can provide gmemfd VMAs like what this series > provides, it sounds possible to reuse the old VA interfaces before the CoCo > interfaces are ready, so that people can already start leveraging gmemfd > backing pages. And you definitely can't get the private pages out of the VA interface because all the VMA PTEs of private pages are non-present by definition. Hence, you must use the FD for a lot of use cases here. Jason