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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?aF4zaN7Q2HfZhEh4ib+/ufwdqA+cqY1CEb/5/wdwDEiFdtWsxeyXE6/N0mI8?= =?us-ascii?Q?Fl84zjc9KVqKyryOXSvgo08QidhrlmtHQhMEf9kf/r/SI5JHS2Hjg5p95j8J?= =?us-ascii?Q?2wIVNLAcaCsAScUxhHQM3j78kD4weuQLT3qDC9dpF1982C+HF9JZ/PMR2lQ3?= =?us-ascii?Q?qSU4ZaT5+iXTF5mShKSU0cahZ7hLDhgOtXJXHpE4va6mN3CgCX6T7IGi3E9s?= =?us-ascii?Q?lrdezu8nxQTz0NMALa+SbkwnxHCEtcxYeCHNQUMRmcv+wUrxhFg3CtxuVimk?= =?us-ascii?Q?ug0RGt+JsOisKAOKJztcZvbbTWDdeTnZpZdTI2bTajUctKQqH3tfIyMM6LW/?= =?us-ascii?Q?TsTk2+MlZ9JpsHa8FrTbgN9L5bKJzqaKwYdSuvStst6YxpEsB9h7n5Qgk0Ye?= =?us-ascii?Q?AycQsbP534iRDy1CJeWCUC06j7en1/CSUGN5138Mcc1aDo9601a5fay7Dsfu?= =?us-ascii?Q?9717Q7zWsqkzVB+HNqlXMEbQv8RzQsvylpEwy0ZtfxuMey+nTMAESeThCJyW?= =?us-ascii?Q?BwElak1XZq5tbCLHNW3I0x1SLBj6ibj/o1PWo3/6ntRJDf3/lSsAN60dGkSJ?= =?us-ascii?Q?SDo7X+rtOhAkkGNyuOLeoj2gqT2W55cR4L08C3LlOmb+DPcT0CudSnvooYKx?= =?us-ascii?Q?/PtgwH5Moe2FJQPYmJVxyosZWYvPz6J5bPEEFVVT+iFgvMqUR6Uya/YETOHF?= =?us-ascii?Q?dQP+1WexXrBRTnT9hB21Hk3z5Ze6KmsKzh9FGA30L1RgtC+8UAGEXLSott9x?= =?us-ascii?Q?IAGVrqFLzj9EQvrsgi6LBHY9Ha5Yp0pTKyecj5vqXUvu49mlPkYAjUGak3Zb?= =?us-ascii?Q?3/5ohwniC0wOitdOncLpzAtZSQannw+yRqyfYYKNOwarW1a+EOCXrKnXs4Uu?= =?us-ascii?Q?EjOoyCT1L6yObWBfRCFsyMnLtkC7nZqmcLKEfqKSG9I57AP89n47v24wVWhG?= =?us-ascii?Q?C+dakFA+z77bbreU7QEXqU5BQzHbZWKZ6OsDuol7qasxnBUvTQMwtOZb3hMV?= =?us-ascii?Q?e3iAhNMB3/xLcEFapxwOOLhTRjzmrSqg9GQPGqQAKNn+3ceS9BACs0xY9rdL?= =?us-ascii?Q?CLD4I2oJ6KODI3P7m30PUB0c2n2NbmJiBRdruyXjB0c6cFVwkGee2Pla2nPg?= =?us-ascii?Q?Vn9dvDUUUzmcTCCzyYaXDpis+yuHl4DpaL1Ox0+wWSw3V/VHkQbHooseBb6e?= =?us-ascii?Q?okLWq2nZhnFus15seVnQScY/qO7GETO8WcoUlewcnhhJpuSYoM7bap0qExd1?= =?us-ascii?Q?n1f0ix0PEe1MeA54jRxKB0whrEVwBr8H1FSSogmWKYbzqtspRr5pB49mfKCe?= =?us-ascii?Q?VeVddYgvyXPwDSvb01Tvf9uBaPRUhEfQ4hgch5hutBeyKk3UFV4RDSUpU5LP?= =?us-ascii?Q?NT6UOLS9nyUsO6S7Zp+Mb+a/i3CSI+nhRx2YWK20g+B/vpbZXjWDI+ywp2pc?= =?us-ascii?Q?1yrWst5Rr7z3mVeLxRG6QrXMswvLrHktMAug76ns+09Abc6mQ2KzRpPY2+ff?= =?us-ascii?Q?q8AoFxwZIpHZbDH2Q/o+NF18aegVEAwzJbABbyGV4/yuGq0AN9unsiB47ZBf?= =?us-ascii?Q?u39bMHk5IpAfYN4y0eeANlARSTs1pWLzhUHt8Rcf?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7457eff9-0ede-4d79-903a-08db612cede9 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 May 2023 16:43:00.3512 (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: z5WsWsHKo0GYiqkhg/HyhL5E4YLc+qJFPtKcb4spZayXjjRqwU7rKALLprkvahjp X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB9199 On Mon, May 29, 2023 at 06:16:44PM -0600, Alex Williamson wrote: > On Mon, 29 May 2023 15:43:02 -0300 > Jason Gunthorpe wrote: > > > On Wed, May 24, 2023 at 08:59:43AM +0000, Tian, Kevin wrote: > > > > > At least this looks a reasonable tradeoff to some proprietary VMMs > > > which never adds RO mappings in stage-2 today. > > > > What is the reason for the RO anyhow? > > > > Would it be so bad if it was DMA mapped as RW due to the errata? > > What if it's the zero page? Thanks, GUP doesn't return the zero page if FOL_WRITE is specified Jason