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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?IiFto2VPSNqobcVogs3FiTAjt4Dh4+QLTZQ6s9tXp6YoJ7EuFfiifEP2vuAB?= =?us-ascii?Q?nU8fdNT8z0QIW7u6xGFXCGy3KpbOCv0kfZVi5WcfmbM1A4hklLeccqrPrBK5?= =?us-ascii?Q?j2+5mV/W5FLGEgPclnIXgj6RSfL+ZDFv4CZmzuqW3WSqhmYFzBtRxrPE4VBM?= =?us-ascii?Q?gfcHHbywHt+XK8fApfYjKIF+TM/TT0w8wxo5Ofm2oog4H2pDkmdTqq//V17q?= =?us-ascii?Q?riLtgYCBdwQw+w9tIQIKuFGaMSTIcYvC7ksoqtfAfPWtLiymC+O8jfWY27Kc?= =?us-ascii?Q?6U0hwXC+NogaYoIo3Y/bK4kip9lRGihNPDekdilM/nyk2yGc3RtqNcS4+GLE?= =?us-ascii?Q?cMTJFMBCq9aBfBz9G9bWyWa7MhWZpQ3YuPBldcFu7h2g6hnG6QCoEPPpgtXS?= =?us-ascii?Q?GG6LYPDnF6afbQ1c6vtuI4s/2A3IDvZcrQPp0C436AsX6eqizWm4Q0gQ0hd0?= =?us-ascii?Q?WgjuuI7ZmiPYBAQRp4U76qxM2QQTpWkKdHafsCtQJvvh0xVKdqW0sef9Avn2?= =?us-ascii?Q?vBVsyn07ay4Zsa/wzXh/s7dlm41BakEl/aVOZppwY3HqQL/ZUQbEHeRvS8Vt?= =?us-ascii?Q?1jieD5x0MFB5y+m8YGPHKn4r/ooK3Pj/A5/wuExLflgAzZuWaSgQqWUtCyue?= =?us-ascii?Q?+C6b246ET9mro/0C1JIpxLyObjAkZl5AT7EokzFCWz+KzOm42LrH6VLjoXaM?= =?us-ascii?Q?Ir6j2fhlW0Ysn9Vqi4A9nGTbPeuz7DZXpvRnU8MeNpKiRaMCYVEQRimqKe/v?= =?us-ascii?Q?/86nazjG3iMpxuSqxkQZe6YOz0D/i7gFSz7tgxqMqxut19KM921d9M2+piwu?= =?us-ascii?Q?WVXFbXd/QIF8beTJrTYtQRJ8HCNf03hv+GkHkXrNNdsTP3sxSKqCP5rnHVGi?= =?us-ascii?Q?rKeRw2HJQfnat7M4El0XK5sU+1hU6mWF8QHgaoIrzlKou6dnjxR6NNbN4HNW?= =?us-ascii?Q?NpGnNXjPVP3h2xuZKIzBXdfDrd7x4pI+hldewUlooDIY0neHI3PXm/d0Xu3J?= =?us-ascii?Q?eOWS6eHK6wgUtG/ZDzNdYQ9y7V6/SEF2MzOYg28iwl3fdrKCkq7zbxWhqwf5?= =?us-ascii?Q?hFSVPtaHS7u6jlx69tleENWPeNE8TP7SfURZGf6QXM4l1lvf789sQIFCt5TR?= =?us-ascii?Q?94YY3nptiO6nSb7p2F/1lCOAWmhUy8wgcrCORwlKfihninLupQWMMy4d+xDz?= =?us-ascii?Q?BGLQUuJAzxoKgdvr7ksF+W/hV3TM6R6/HML5ZJy6DscdlGJZnTo9nZgWP/r+?= =?us-ascii?Q?kYit7xZuGxh77kV8qQxIcWH1+cDv17C/R54fDaNFjwDrYBN6keM1zj9s1uWI?= =?us-ascii?Q?bclwg2/HSWww+sP9q6xIErsecSwYUWkwVQ3pYMqGZpxgDZqNrlca5iswdknX?= =?us-ascii?Q?m9FjOuPLTWjfm7b0OSYKmItLmKqoBNkrp6IaSLaQvDLaWivyY4fr/3kwTZQc?= =?us-ascii?Q?g+lOtK0kt3y9eJ0ZNKqgHSeTccJQngK5q1CAqfNasGZ+NNPXhJj/2sxuXoJM?= =?us-ascii?Q?gU3gZXWRf2MkScnYOBKCptpaahSs4JS6l/BJITozpno/IB9DMwLEAVzxZzQT?= =?us-ascii?Q?tVkQf1GOIk+QSq+w2ZUh0iqTL9j9w7ayp/lw3etS?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 017ee359-bd86-496c-ac6e-08dcee3ddd61 X-MS-Exchange-CrossTenant-AuthSource: MW6PR12MB8663.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Oct 2024 23:54:25.6030 (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: JFGEwACqtSLXwWHj4A3D049543WYIFeGg27qTIHCo/wMJigauUfKDPSPjWomiQt0 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB7222 On Wed, Oct 16, 2024 at 07:49:31PM -0400, Peter Xu wrote: > On Wed, Oct 16, 2024 at 07:51:57PM -0300, Jason Gunthorpe wrote: > > On Wed, Oct 16, 2024 at 04:16:17PM -0400, Peter Xu wrote: > > > > > > Is there chance that when !CoCo will be supported, then external modules > > > (e.g. VFIO) can reuse the old user mappings, just like before gmemfd? > > > > > > To support CoCo, I understand gmem+offset is required all over the places. > > > However in a non-CoCo context, I wonder whether the other modules are > > > required to stick with gmem+offset, or they can reuse the old VA ways, > > > because how it works can fundamentally be the same as before, except that > > > the folios now will be managed by gmemfd. > > > > My intention with iommufd was to see fd + offest as the "new" way > > to refer to all guest memory and discourage people from using VMA > > handles. > > Does it mean anonymous memory guests will not be supported at all for > iommufd? No, they can use the "old" way with normal VMA's still, or they can use an anonymous memfd with the new way.. I just don't expect to have new complex stuff built on the VMA interface - I don't expect guestmemfd VMAs to work. Jason