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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?BMD8tzMgooQGbUFV1y7Az+aU90HbVozMFA/UKXooj9L3J+yAmwkvzHkyI7ST?= =?us-ascii?Q?OQ3O/6Pd0zfgRRQwTRBSAgKICaU7+sSv3loshqD7/bBYal1UE/406J0oS5+w?= =?us-ascii?Q?e4gYJw7oLSex301Ct3WUH+azdNGYdz11OJkZz1rPcRyJH7KA2l35TRseGAhU?= =?us-ascii?Q?ZmMRGVc/LOOjnvd/V8+IHIjMrq0GW5btsP/6wHFzjJc9+Z7CUXY+nfHT5Wxw?= =?us-ascii?Q?KxwOo4IjMQOcDloW3C2nEwSPpdTEuHa0Gy0zbvAflNPoZ+gGowiABzEElJuB?= =?us-ascii?Q?5Gkv3SXR3hoPoXEzRzZSsNVY++f2HUVJw2/ji7Wu8Ir8pNKqpLNa/F8YAuMs?= =?us-ascii?Q?ykkMqQHRW3zRAcX7N8pvSFPwH6fgzcghwclDAbcEVDl4+Tl3pPnPDTYICSDs?= =?us-ascii?Q?EeDRqfJcYfVDEfRoayopzRM50qTlpgGBnbPZc6SVspFDQGTZMRGTSpdt/DUN?= =?us-ascii?Q?C975/7v1/rGEqktd7/BDXWH0VOFWa8h7HJSpcjhEn/jL8fz5rpbPg/vgpZQh?= =?us-ascii?Q?j0JSFIrUz1trtlgtOGzaOrv7eCeDmiS9TUVMCT1SAZhnrcKheDXKL+pZkdO/?= =?us-ascii?Q?C5AihT/VSrf3GNMvDPrlkEk4OsTe4fLqJKbJNNxwRNiFFKMT65Ub4I4xLs6J?= =?us-ascii?Q?2cgVhX6jz1Fr2RStw8CwmocqYVJQGbpA6OeaWVp1mWIC+XD8E+3v5yZtwRIT?= =?us-ascii?Q?Ui0OXPPwzgB1WHFa5fE3N4ux9mLd6StF91qa+tG1BUf2f8d6fjpDtQADvk60?= =?us-ascii?Q?hogLXCIBHn/9zCUZBFq0RpoqZ4o871z5dqbq8ivfETfIQlfllSfbkQa+gUoN?= =?us-ascii?Q?+OcgYY3Ez1qBVZ6aF/fC0OVDI+73Wx0AjdyLDoBIrxmwO7reSDenyLNL3wPx?= =?us-ascii?Q?YW8J+G4DVZ7qr/Ef0l+IPhfLHG5WPcQF64WlY0vN2dqhWPUE7KClJMiFnO5r?= =?us-ascii?Q?MNKvGaJtVT2/aolzTQT9Xvba4CISMSsOCIcftiN45Eeh5gHSFW6SOIRBbGp3?= =?us-ascii?Q?exjdskpT0ZX+NXxVuURNoLkt4hsws9BMUrDmcXZq5JE9SRp5jprYqa0uCh1W?= =?us-ascii?Q?ZcSx6Qx/qKeVxibzTx0PE0pbntmU10zo4PEig/aemH5afKHVgIWJgQh71bgy?= =?us-ascii?Q?JBEHgbFoCqMK1YlbI8vkhrG5ho/i+rnEr3ZXZKzUYEYFzqDiOx4b+ia+q0mX?= =?us-ascii?Q?3izA+GRT3PXRsFlJtV+su9Ssbr6lL0OuU2OUwIPMDcXcEKZW6EMIcP2YWAH+?= =?us-ascii?Q?jaQmIxJio1WQnOknjJm9eMuTXg6NpItzTcg2T+n3sq5KIBajycFcfWygNQro?= =?us-ascii?Q?EzJxzqX0p2J8XsFWVFYQyEuQukIqxEGcog1NqeCiHzCYExYkj7hsJ4DVuBrF?= =?us-ascii?Q?3MhUTwV+rdXHERl3GC3+w8Nf6ertT07TKojsxDavJW56WVxqAGaGVSkKDEa7?= =?us-ascii?Q?qgLd2pDVDq1BSL5cQMCnfRqNnWA7O9wp8paH/XFEUZD4/+TO0jooHrwZHYxJ?= =?us-ascii?Q?XSdpcfCHMla4Km//QCBJ7nd+3+ieS2/iIcP89k8WZswgMKj8pCo4jEvBZS/M?= =?us-ascii?Q?IcYZngQs6EDtrmqfc6DdNkcFA6s8KPCRyl6ID6DI?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e0feaf00-f039-48d4-c171-08db0845b8d6 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Feb 2023 13:26:15.1310 (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: K8nIaN4xiaa0Wg1nR35ENVy2UbM4iI5lts6gcR7ryevFC0RlZbQ77CWQ8VzXk/81 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB4939 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 06, 2023 at 06:39:29AM +0000, Tian, Kevin wrote: > > From: Jason Gunthorpe > > Sent: Friday, February 3, 2023 11:04 PM > > > > On Fri, Feb 03, 2023 at 08:09:30AM +0000, Tian, Kevin wrote: > > > > From: Nicolin Chen > > > > Sent: Thursday, February 2, 2023 3:05 PM > > > > > > > > QEMU with this feature should have the vIOMMU maintain a cache of the > > > > guest io page table addresses and assign a unique IOAS to each unique > > > > guest page table. > > > > > > I didn't get why we impose such requirement to userspace. > > > > I read this as implementation guidance for qemu. qemu can do what it > > wants of course > > > > sure but I still didn't get why this is a guidance specific to the > new replace cmd... I think the guidance is about the change to VFIO uAPI where it is now possible to change the domain attached, previously that was not possible Jason