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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?68Bg7QP8WVdu/0EzOwh7AI65RzUFkEoDFWkjflhq+cJclJFdFXGC2ASnVlKK?= =?us-ascii?Q?R6AS5VFK46BjoH6SyDNVVyzOO1/UeJvZ0aVJ8EMof3IkeTqM0wUS3bZUtHn6?= =?us-ascii?Q?8fFq+Za+ASgyFPgXPGJr/9mIGPdsdssKaAdYcSES+GssqKdFPq/jnsI7vWrB?= =?us-ascii?Q?IFtIjD2CPPkTdEiN+VaPjuMrfrFwDqBMKrSFLErJZbPQcbBfnVWFSU2i0zoF?= =?us-ascii?Q?x4Oa8ZoegLMLaUl133YSKKwXrfGRqlmCHSDbL82TZuT6WP3XsPQUpkPe7R9g?= =?us-ascii?Q?MAsfk4SoQU2tq5Bt/m0jGxHzmJ/c3SUtlWwBwdHHAz4zfh61NaNpkywXAnah?= =?us-ascii?Q?c/WWRy0vH/vVTWxE90PfZK8fIbJhSAJnQiAVyVniloIOk3pVPtg6LTgSb7yu?= =?us-ascii?Q?AzGfLCukEgSoWVGDQoFeQWd63AlrMOIPsH36xHoB0HuCjArReou0dVqaUUwR?= =?us-ascii?Q?byimpmE69+te5sav4mqIodMtrgYrN9m5bJNoSZ+tqU1RmPeE6PC2NFFNEz+s?= =?us-ascii?Q?e3r+0QmacosB72TUQJJWx4YmhEahiSBfdy+BQv3NS4phGZJrObaJ8Ur8sIfr?= =?us-ascii?Q?U8EofHrrcsGNzVInhu4sg2ZzZHFc/gu9pNEShQgO1YbobOI4vnYDdCQ7gnNF?= =?us-ascii?Q?fy2aOV+9xY/lFoAeSaU7oRJ4pGOnht/tEh34Y+9u0wjPU405y9dwUOL+MeKX?= =?us-ascii?Q?PGxUSDiANPVB8oCXrVrztA012gBXNYtY5Q1NYI9V2vgt6QQ5j0XjGS0WS0O5?= =?us-ascii?Q?34fdr401eVeRDy9z8bKbEERXfyksRpoxEuC9NWBdQjE0IEr3kBcvMtv+H7UY?= =?us-ascii?Q?jw6M7p1tQInJcprAXWaOE0x107mOxmsyGJ5tpj05yi5AC9guMTyeip3C8MwJ?= =?us-ascii?Q?AL0l8Ei27QPmLYoCEQrZHtk+L2pqxHPek6RO9sEJ79Cl3/y5dbEG2RE0V+cW?= =?us-ascii?Q?/un186hQY96tedQjCXSxQgA8/+y9s/f/ixj2UhWFgKFNP7iy+WQtwiOE9ZEa?= =?us-ascii?Q?WR24+C2wMWBGNAl64WQOkgxNg0X5QdVBIrTPDTaJGafVlYLDAw9xyWb9FAk9?= =?us-ascii?Q?EEw18PqVbkCw2tXwDuoBlVAjqSag+iYCcP0k5FVyXfbH2YnKVyiTmMsX1JPV?= =?us-ascii?Q?r4kFpdevfOwGwppGSQquliu19UdlUjYEEwOxl2lP+7kieSIEc/uW/D0MAvX5?= =?us-ascii?Q?5dOEhBk59BDuZ1VVh9oOVeMNl1fLbvCVWx6iP29NvCWI7J/pndQVbXSfd86x?= =?us-ascii?Q?pR2D+lpfI0IFJTaC1p10MWHVyC04b5HNq8qAE68ZGzAg0pp2lsTcKHsbCRqJ?= =?us-ascii?Q?ISHfDWTJZg++MtpJs40CJljAnBa5jXy6eyla3+3sI1Xe+mmjlLH1bGUS+ous?= =?us-ascii?Q?ZO96Pg/VphZcaF7HX0iy6zKhjHovMcv2Qd69Ldiagfx6fv76YXrqVSRFyBsP?= =?us-ascii?Q?CcTo4E7czJRM9adSStoVsh6ahSYGmLaa?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ca5eb563-fd22-44bf-3fd4-08da08e97354 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Mar 2022 14:13:18.2743 (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: EnwlSr0xEeBt3UliTUBwHodjadpiet66ShF++m6Qq6uG1xX5vygFWexHwVJv+3TL X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN9PR12MB5066 Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Fri, Mar 18, 2022 at 02:23:57AM +0000, Tian, Kevin wrote: > Yes, that is another major part work besides the iommufd work. And > it is not compatible with KVM features which rely on the dynamic > manner of EPT. Though It is a bit questionable whether it's worthy of > doing so just for saving memory footprint while losing other capabilities, > it is a requirement for some future security extension in Intel trusted > computing architecture. And KVM has been pinning pages for SEV/TDX/etc. > today thus some facilities can be reused. But I agree it is not a simple > task thus we need start discussion early to explore various gaps in > iommu and kvm. Yikes. IMHO this might work better going the other way, have KVM import the iommu_domain and use that as the KVM page table than vice versa. The semantics are a heck of a lot clearer, and it is really obvious that alot of KVM becomes disabled if you do this. Jason