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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ry8N+q7/chjrYvy89ErkvEU9Ypp/Kl/ZhCxG7JlbADUPYKfcdeqzMHfkMp1S?= =?us-ascii?Q?ldzBhC8eep7XE5NZcGgYct2PIAhytgBe/tmpBX45beUVSe4iHl7lIgWaISsA?= =?us-ascii?Q?kg6QkEoNtnEQZzsL/8LBYAsyhsctxbC7fSg1L4DWQC++TphOYOMQaGZRFTvr?= =?us-ascii?Q?/P9nfKiZRzpSM29gGREIG8sHTwY4tfzX015s8tZG2AX9nU1jawGtmyW8XZ8S?= =?us-ascii?Q?dYh2LV8ndB4W1+WwZZnbZUGNpGXq316UYfUnliU3otPnwR6Q3d3aEHHeGfE9?= =?us-ascii?Q?jf7zD+Ht1LwM3k2rpv5xIz69hjcGbSjEJCYQMh+BVEituM/MVo+gt9eyyTlj?= =?us-ascii?Q?IG2KMldSQvyvYtSYgoeS9TIQ6lMNzBzU9QVqiDwxRcCqpnFwfGY1eyNJEZWn?= =?us-ascii?Q?Zq5WBsvXIU6GH+k0jBjneGYZS+ao7hF6b77VkaaXo0zK0jcgF9r5BXfIfS/A?= =?us-ascii?Q?BVooCqn4xD+iem00Qg8W8n4VR5budMIaZ3CeGBgP/PMhHNE+sctatT+eXSIc?= =?us-ascii?Q?qLIjY7y2Znjqv1ch48XSUUZuWmXibIEQ/arpiMXgYPF/JVJ3c3iPYcsMQsqI?= =?us-ascii?Q?ECZtTWqIKT3TqEHQnX4lDzLl/Q/fdVBmsBwyALYgHE8masjVRhnC4qraKJ10?= =?us-ascii?Q?XNssrA9ywfApVRXdDANHTCDF7QQRWIng0zIPomJgrDEM6vkHXmIBLG8zSgUs?= =?us-ascii?Q?aDyLInDx8KsSYz7IF3OMLBRDg3n8hHBFo9JjZPzhaFW6RYFz2mL3V/6I6hgf?= =?us-ascii?Q?501E/EMlTiasAojFvUQcXxU545bu7cske7IlVVgMWkxdE37ClnxDGiCrr7mN?= =?us-ascii?Q?BKD7OYTT4AanCOtnwab6HFcAMBRHXF3x63jvB6OEQJH99TezBYJAKYJwp8rj?= =?us-ascii?Q?35z7CeExrvcWX1wKP6NjOS3TyMQGDD5XpDO8HInvd+qEYevjXnjqF6teDfwC?= =?us-ascii?Q?npKIbekhAUtvJLYrpJQ0BGmgtcAHZ+Ms0GFqj3vUsC9Lt2J/JRDPv/IQgMNd?= =?us-ascii?Q?ZwtRy3WtrbAbqe9p4n6dIQEeAOLJUP0zO4qTCvFduL6vaprINUudWAMjRHlb?= =?us-ascii?Q?K1p8tGc01jano9LLv9b1djK6WJM+3yrvLagDT67h8jYJHvfn2qfXt8qjaNib?= =?us-ascii?Q?r1PNH3tzOPinAbJ6eq94yxPKiTRav+L15ubXLhQcr64d1xhHgXYrU6WZ1Qn7?= =?us-ascii?Q?xb7zTec9h4ovBXg46/dSQeDDVAb2xJZ4snyXv2Cf9n5ih4Y0s+usYu9JpS/c?= =?us-ascii?Q?vhCapOWx3f3TPjX/FkLLEXzfnDiuzu6QdAeCgJIJ20ZhSMCNA8fngWsmirOL?= =?us-ascii?Q?wWtYVDpDku8kpwApgKD5K9VtxLN5zNTwx/phjBhRgP91T7Z2GMVJ8tyErV/s?= =?us-ascii?Q?UObn2IYjM8RRx4kwY1XmQwVzs0iRscUAUzj+yOSTIDSQvjiIoNdwrwDH2eDr?= =?us-ascii?Q?M3mV16CS45miVHkaKQf+PoQhy4crE7hP3CqsjiQCx+KrPLTTs++vSHhpF29m?= =?us-ascii?Q?DAeh/DMC/ctk4vJSoHeESVuBVOD9OAEGgBlqIJjqcehXQ2lq8ao5iu6Uz+nD?= =?us-ascii?Q?h9RjY9agD8GEGN2sSkOZ0HqQuxiOypvnVQFbZJLXzz/fYnTuSObWL35yHbQv?= =?us-ascii?Q?8g=3D=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: 2bd9fe91-55ed-4130-cfba-08dde64af022 X-MS-Exchange-CrossTenant-AuthSource: PH3PPF9E162731D.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Aug 2025 15:52:48.8642 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: np0BJJqrzm8jTdPW3aHCnjETuR22B0XUWSHeyd6mBYffhbLh/j4bBrhyL6sJu331rqZjg0i5tlSCCANws50N4A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR11MB7204 X-OriginatorOrg: intel.com Yan Zhao wrote: > On Wed, Aug 27, 2025 at 07:36:46PM -0500, Ira Weiny wrote: > > Sean Christopherson wrote: > > > Don't explicitly pin pages when mapping pages into the S-EPT, guest_memfd > > > doesn't support page migration in any capacity, i.e. there are no migrate > > > callbacks because guest_memfd pages *can't* be migrated. See the WARN in > > > kvm_gmem_migrate_folio(). > > > > I like the fact this removes a poorly named function tdx_unpin() as well. > > > > That said, concerning gmem tracking page reference, I have some questions. > > In the TDX.PAGE.AUG path, [via kvm_gmem_get_pfn()] gmem takes a folio > kvm_mmu_finish_page_fault() will decrease the folio refcount. Thanks, Ira > > > reference whereas the TDX.PAGE.ADD path [via kvm_gmem_populate()] does not > > take a folio reference. > > > > Why are these paths different? > > [snip]