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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?PP/6uM3A7aRgjy5635Ioe8Fy4Uk04JmBb1B7yp16xRVpSVSrca5isDQA0EZa?= =?us-ascii?Q?yP8odGKGEl4L0b+NbgH9/tXw7j4P3Pc7mSvNyXXWkm0dYuV4dHwlQ7ysksWy?= =?us-ascii?Q?mcC/B2O9VR4Cg/j8U86DlEucdd3hDX0+aKS89bGOsBJXnY43IMp1R7XtGtL/?= =?us-ascii?Q?D12m+FQ0kWQaA1n15OlYBJpCQRpQB1IW3ejW1T7hqQuuN4PnWCrmdtS1KRNh?= =?us-ascii?Q?4jY8Qox11ErJCDlIKjjRYxjYo6D5AssMbqGEfNsJt5yVZQCPP5p4dcLeRe+v?= =?us-ascii?Q?2UJSJFG6qy5VynthH0qZcu7wrdwj7dMRyMKtFLBhkYyNsXFhodVrcMTOYcGL?= =?us-ascii?Q?AJmwx5QG9foCZjztUrklb0YeQgHcqB+BSMcb9dY/r2pChCjyKs664hTMit1L?= =?us-ascii?Q?GTest/BuszkMip3DzRiq/QethmWK01RaCcGldQyzsbo169xaLgb7HB/LA2eS?= =?us-ascii?Q?xp1NMOZuWwD4iWpTvgV49ltKskhUl+sOnKZVMbLxZtYPWcuUGxki56JuYtrG?= =?us-ascii?Q?T+Oj8UcRb5sHO/AAlupDXRvZ2g7CrI72Pe7BoH45KOIZnKVYFzDa0g97w3pS?= =?us-ascii?Q?SoK1Of3JO6x5Vb+XuCw3SAu99WFNIO3MTTJ0b8lQqkRwWaQtXaW1Czorbr40?= =?us-ascii?Q?s0J1ZBLZjwA6nn7MadMzGL4iKIrqoTzfs7drET1fcCxWx2p6l6fRtdF3CO2l?= =?us-ascii?Q?MFJa0+QrtpBgtmsnu9Ms1Y4bOeNGY5BnD9AAXHBmvaXmabySm9yXtVkbR04n?= =?us-ascii?Q?jPH8AmF3B7pjgsQj02W4jWOKdVpv6ndKCLJkrDRg2NZ8knNwZjVJNR5B/wCi?= =?us-ascii?Q?ZGARIU3lNKqKTiJWBrmKmqrLEb2BJkQ4B7UQo3cwOh4405p9ADyoTP+Epco4?= =?us-ascii?Q?oXeB5OXD3n5MlkZ+DPe/1ZXTDneaIMkPClm4A63T0EAic/alaMcKub2WM5Te?= =?us-ascii?Q?T0WcMrPxgF1rE0G6l1e74ROFHiXQU0kXM3yBufQqCRQrYlvGmvg4WWdZt0eE?= =?us-ascii?Q?ELO+tObx775FtAMgYrvM2rDyGVM2HIVORPyziPN4kPZdVG0X8v83LseSlnzz?= =?us-ascii?Q?KM4G++qOc83QmiyYhli9UU7fMFoPr1uQomQsWFJMDYqkcrcXFQPzVUQoODz4?= =?us-ascii?Q?JONyfxNMLCKeY5Ls3jWYihn/snpIkxtaqBuNPIHfuG8t6SxKaeM21TcwKOps?= =?us-ascii?Q?I9a75hTn6gNHr5C41iEFcbtRc641FA1ctfft6cI2FXevbimotkuViGgx21YO?= =?us-ascii?Q?zJr8I62/iI99kGIBC7rxeW7U5poVyW22wLaXCd3ihHdzTBOyb+x+X6hESW0J?= =?us-ascii?Q?Ashe4IERR02ehIzeLgo7uS6u3vP7tWHNgwoaifihrY+F5AwDuNzIA1D86HqL?= =?us-ascii?Q?tr3/sc7zJX6JFsMqCODt5OingKVSsOPTxkuymGQeV3UxBlsXdAeQtm0eFSiq?= =?us-ascii?Q?knz4fosr8UdsLDxnkB8+CjqC7nAT/JgwfBGUXzFtatCe81JLLvP2zvlS8rdw?= =?us-ascii?Q?gbsfGhlgVC88GrfV5nuNWyEs4LDETur/O51gqmfQSY7vSnHW773yfwcyRDqB?= =?us-ascii?Q?Fb+Lok/5dmpprts22q+H2E7dbGDmx3E/iwoolCFVyiV7QQlrNB6ODZezLgut?= =?us-ascii?Q?gYLpq2f3dWDu5u435JGCarg0wlo6u6oa8hHonlqIMh2tPg9MuFEWcrqFFTDo?= =?us-ascii?Q?9QaAQz6p1cIpkCYBjfsURHM2GiAbUsXHQmhcmzuV7vxFO0+D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c652ef0a-4174-4e03-917c-08dee063a7c7 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Jul 2026 22:19:35.6936 (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: 5vCmbWngIZj3sQddl8ImYB+v0kJNuT3fM9CizR2Yk0OoCtju6dYYgOiPy1yIfPd4 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR12MB7002 On Sat, Jul 11, 2026 at 06:01:31PM -0700, Ackerley Tng wrote: > In the course of a CoCo guest's operation, will the guest need to > convert between private/shared MMIO? Will the guest need some pages > shared and others private? If these are required operations, guest_memfd > already provides the tracking and is going to have a conversion ioctl > very soon. Instead of further extending dmabuf to track more things, how > about letting guest_memfd track it? Use another FD type was sort of my fallback if we couldn't get DMABUF into something workable. I'm kind of surprised to see guestmemfd proposed as the other FD, but I don't know much about its insides. If VFIO can create one and fill it with MMIO physical addresses then maybe it is OK? Jason