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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?K4yeB/prNpvwLFst6Ubi9X36AiAmP8YtLSzfqihAnEDbf8c9PvaGD8idBmIz?= =?us-ascii?Q?pFzL4jafgXJpkZkr3qwdqBRD46NV/+6zjROYtjxicgoGOvb/WHyyf0f769/d?= =?us-ascii?Q?w5V5GH8ohqcu6iafMN2aRQPVl7f0aVie4M3X1XqJm7r9+ATxPG1UX8Wczdah?= =?us-ascii?Q?mvZUfXnm3DBD0eOnm1rSv2mN5iPJOn8XhhMG/r+sDoCsEMi/36xkvQzsy7Rq?= =?us-ascii?Q?NM9yYudsN8iT3/fDLV6dMAtrFdQVPpZY6IryOTkCKR8DvQ0jdG5aJG0ucKp7?= =?us-ascii?Q?bQ+hDX969Ru1pxSPXAz5M/IvuHS8100w9pFbPCfpmLHw4jFprnXUB08n27Mt?= =?us-ascii?Q?ULaWxssJiHafEg+RhxWFX7FIXbCjR9zLsHdikGXjbYI/2PIkcb50/93tGaqH?= =?us-ascii?Q?sRvptYUceG8eHtGQHfy/x3qV8NdgS3OeOmCdndBO5G8NoXobGJ3X0vZC70F+?= =?us-ascii?Q?S6vP3z8WtgQIeaIVOhvHRHOWc2daO4F/oSBbTyWV8aO4e4CpLcLbIcEYDl1a?= =?us-ascii?Q?ZxAQ+EfdunaEBw5huFcS51P9CBOruDMtNawUU22HKpgeFyCFs8HVZiL2usHS?= =?us-ascii?Q?qKc/hiyf7ML3cbk5jJorC+VvwFIZsYL0RXh02ZZVnBkwUn+JUjrC41LPAny/?= =?us-ascii?Q?VOQXdluRn2+yCHVmH81sxNWwiSBynOygB2MX+BsI0hENS0caa0VlR0ujdcyu?= =?us-ascii?Q?7Qj8xBpj7M9kIMy123olWmwHuHMdAt58uj7LxnlCwfkXpmZP0LTFuIMS5crq?= =?us-ascii?Q?4Y3P1yAOo/VuP/h9iYgVr2VW9d7xE3GeOZDUN+SjXZ5qP6mIKwdaehVTcfZD?= =?us-ascii?Q?s25nOAcd8iYFTP7emnDUOS253ywEz0nGma3UPx+9wMQzIaJmUKihvGxF9bA2?= =?us-ascii?Q?oMsHXwj5Gs3x9uNlXddpoMBe7fX7q9hLiY1UbGLZO5Pmef9cLmo+p9RmL4cp?= =?us-ascii?Q?AC2zQnyLdQlaCoX/GIXWQx9u59xcN/15JGebiVPeVIF90n8RK+MLLWsjCqc1?= =?us-ascii?Q?yxXCJepg2bA9FucVs0E72sC+1HJyOXstXyYR2vbrbkA/WpMwUyqs0c4TCmMN?= =?us-ascii?Q?h0jE4Fl9uT0mKJKPPFB0u8ME//KKnVju7tSWbu6tbryAmZ6XeMhM6B1KnBj5?= =?us-ascii?Q?NWbj/9FwBClD3kL4fduOlpUWNWOIlMhXATs5JmQiwpgIo5GB7Jn3ZZlE/jqZ?= =?us-ascii?Q?WDB3kM85JvPd7rNFECURP9M0oDP8aIBFwWipZseJ0fOOwVvyZFzP9V5niV4W?= =?us-ascii?Q?GsHDW1iVjaqmP5rJC3QxUXzT1fC9rq3zBDJnU8hlwbMPyu3ChLS7N+j1kd3Q?= =?us-ascii?Q?QbYtdepXxtov0HLIuBuINBVHeYptpm+maznIJe59sWl+JrYCRyHK84gTkAY1?= =?us-ascii?Q?6Y55+SbOU6tqZ7ZZRCUaxBEBjwbe0euu1HLorqz9ZswNfPI7rBIloI7dnXRr?= =?us-ascii?Q?qvxDvP59oyu4a5HrT7qUQ7T3YGuwBdsHbEpaklOPuWR93xP6FLg0DONRSJYK?= =?us-ascii?Q?W/olxFerkCo00qTzFjX6CH/eMQuI9whlBFIud9teDMmcreqnXQGHhD94kx9C?= =?us-ascii?Q?PZMZCu2S1USqqe6MvcMR8WtWYIiDMC/4bKiva1S2?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: fa8fe85d-4c16-4bba-c89c-08db090cf89c X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Feb 2023 13:12:32.0214 (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: 9QZpf0B5P9r89ClBNTXHdFUHb8Sg5nHKE0Pmomn14HRVWkGSx9GiQ0TINCiyDleN X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB7784 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Feb 07, 2023 at 12:35:48AM +0000, Tian, Kevin wrote: > > From: Liu, Yi L > > Sent: Monday, February 6, 2023 11:51 PM > > > > > From: Jason Gunthorpe > > > Sent: Monday, February 6, 2023 11:11 PM > > > > > > On Mon, Feb 06, 2023 at 10:09:52AM +0000, Tian, Kevin wrote: > > > > It's probably simpler if we always mark DMA owner with vfio_group > > > > for the group path, no matter vfio type1 or iommufd compat is used. > > > > This should avoid all the tricky corner cases between the two paths. > > > > > > Yes > > > > Then, we have two choices: > > > > 1) extend iommufd_device_bind() to allow a caller-specified DMA marker > > 2) claim DMA owner before calling iommufd_device_bind(), still need to > > extend iommufd_device_bind() to accept a flag to bypass DMA owner > > claim > > > > which one would be better? or do we have a third choice? > > > > first one Why can't this all be handled in vfio?? Jason