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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?0lQ6AyVZtZw9sN59NBGBRxd7ge/fm4F9LgsTv41pp8uqPYsnqDwJ1gKPRe3X?= =?us-ascii?Q?YalJ7QjKVnFladIgE5oDRoI5KAnFEajjCM5gtlMuFajTi8NkgUVGYW+KUQUK?= =?us-ascii?Q?puVjBZk0XCmjav09tdZT3n2JefA8jm26PoUeIWNYWZUbIgP0AXqDYDWaIl3c?= =?us-ascii?Q?RVtwRUK1pT9FU4nL09BJGjpUe1VNyt5a5UwExlATHkbWviTPR5+3fYfrkXKt?= =?us-ascii?Q?bWILt8cKfycXmuoanuUaFdEGwxGn++pkk3xnxh38rfe7B8FcnWEhNJdlwx3G?= =?us-ascii?Q?Jsi+8hNyWHrfo+aJTH1VbhMWpow+oVogywfsf8d7cVLj9DuEr0dgcqwIB3aN?= =?us-ascii?Q?wNX452UfwFukjS6PUVJjQi9f+28czIAjC8ggintRYnahoxG11cYiayNXkRhv?= =?us-ascii?Q?6L/3w98MRsGD/i8wfliTQ+z8PM/gh+GA75Veq1qUKvJfrSZjNQE2Tf5gMVtL?= =?us-ascii?Q?xLamQL2rJo54LpuuoyW0UA9+0FsA8TQSNPALOb10pfVi5eMkFYpL+DOYTluM?= =?us-ascii?Q?+xtvBGEhyAZB8sPngwwVaWPkhXTlGDziQnDnYgCYbcA35BcDFJtbiQGbu0yz?= =?us-ascii?Q?wJRRkYw07iZhICnuVW4rQuk2L4IT9aDGjmPktiOz+9ENYNA3cQdZn2FEJbXN?= =?us-ascii?Q?HaA7aOPTN0eEjim77jCSOos3lYcyMjDQVpbIkkPtNGXl5G/kFNXAj+X9Yzuo?= =?us-ascii?Q?9glE8HvEQJg7zXv6mhAxgz5Wawz/UQDwNCAunrAhB0WMACMOZPNf9k6mqgpd?= =?us-ascii?Q?q1pNNE+huCYdL14ehIuUppXTdVqXhzAv6Z4xw4iYoaCSPNxrOuWaEn373Kho?= =?us-ascii?Q?+EeVDQf+vmB4zozhEC1Xn+WCX5J9+i/V1Aco6/L1TfC57DelGP6UKjqV1Pnm?= =?us-ascii?Q?ZKOifFz2EJas3LCCVmW4gPbPtYWR4Pn9V9Aaw2NAJWK8WFj06xxexHs+aWsK?= =?us-ascii?Q?Ao2BAXBxgMTFhp/rj8uGze7TrvtqHogF/OnLfm7wq97vTvpngcgDlfPk1mvG?= =?us-ascii?Q?MKOuzN5gEYQg4W8E3elulgkzTiZObHi7xOwuaEV5JDVu3iPGPCt7deEqUapW?= =?us-ascii?Q?z9VY9/1gFPnKyfvuOFGmxG2l1yp1tMIIA3NbGojWpCGVYzZYgzrzoHHwXAws?= =?us-ascii?Q?+vFGNwcAhu5r0xHIdnb8yTHFedT66vOG/FDvKYQuqApAyTf2/rpYSzlFyikL?= =?us-ascii?Q?lg6As07WVNkvZVfFog3N3RR+tEJDMRY4blg2Rrevd9Xqol4VVDfpNWnl+KUR?= =?us-ascii?Q?A3A2bu4Cy3l4D9D/ehopQ3XCH8BGsIptOU9+VReE+nT/uOgMYOZBu6Z7XDrh?= =?us-ascii?Q?5HRev2WRT6/1yi+vxVYgybknlxcwMYRnzgIOQbn/aT3zVKUNQaaUvq7pngmR?= =?us-ascii?Q?FSQzSaNaNUvKd9NiZYQvjunexeY2B5V8V+cAD1IsfyovjhvNuDB6JroP48kJ?= =?us-ascii?Q?EIaN3ufAvIN13crmrsSGDea0jS2S6ozFAsjbWikKTNSCzZ1WUZ6htOOnBF7f?= =?us-ascii?Q?Oyx4a7Qpb2NRbAJTtABE9uufmHaso2hYCrVOczpkrooVoqIl2D+LGBP6GJOg?= =?us-ascii?Q?xbzY1MP7ZF83cVyo/FU=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 80947543-5617-496c-2841-08dceee07c08 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Oct 2024 19:18:30.2512 (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: QgkZHq0MrylMwcAZRHTg6fFcO1yyeQzMCk7HQM2ULpt2nFVCy75R0AH7AW8cF9xU X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7379 On Thu, Oct 17, 2024 at 03:11:10PM -0400, Peter Xu wrote: > On Thu, Oct 17, 2024 at 02:10:10PM -0300, Jason Gunthorpe wrote: > > > If so, maybe that's a non-issue for non-CoCo, where the VM object / > > > gmemfd object (when created) can have a flag marking that it's > > > always shared and can never be converted to private for any page > > > within. > > > > What is non-CoCo? Does it include the private/shared concept? > > I used that to represent the possible gmemfd use cases outside confidential > computing. > > So the private/shared things should still be around as fundamental property > of gmemfd, but it should be always shared and no convertion needed for the > whole lifecycle of the gmemfd when marked !CoCo. But what does private mean in this context? Is it just like a bit of additional hypervisor security that the page is not mapped anyplace except the KVM stage 2 and the hypervisor can cause it to become mapped/shared at any time? But the guest has no idea about this? Jason