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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?4IYz55st4dqTXtMKBFOjO2+jGLjQ09j8jqVMiX2tmqx6wwqG2JsnAG26abGW?= =?us-ascii?Q?C3yaecQ/n+oEaafKkv5DE07rBMxd6n3kxsvsa0ff5pDNgLBQAv7Mt3WaXKBw?= =?us-ascii?Q?MKkDIRokLiPoSjmO8lY2lhDGPZr82SKW0dsZ7nyaZohXxkfuVTx8MACxiwTV?= =?us-ascii?Q?01gO8abEbVQHdSqZD0H6UrDRXdIfW/7gE2tHc4Fg2b37bXlVZ2VxRu/SD0Xd?= =?us-ascii?Q?lYJ6soG9dvx783wUq8gdp7NJYLilCUYB/XfCGw/id+SXmt4J7gX8yYX3Gs24?= =?us-ascii?Q?6L+XJwNRalIGJPgkAhJaofGFBgD6fUFDDtKyqLiwrGaWAWHXPlrO7beHV5DA?= =?us-ascii?Q?lco3gZtUD1c9NjPMUWI/ivgKh7F4+eJz9Hle8ck4yqPUkrEWClmmxJZBOjc4?= =?us-ascii?Q?1jqz5RKlsK3JZX4RY7Uk6Shu607epLqcpYtYBdDRBKodVoyNB6fncPGrOM6F?= =?us-ascii?Q?SVF2BEEBva+FWWz7qTTvH/gOtNXMlW7Ad4UpfxQ97ALIXIjn8iHegWW40kvC?= =?us-ascii?Q?rrrvk2SP7tQIH1vNGbsjHI8u0OwN/m4i1VteFd38YV1DnadtQFlAvK/C9qjA?= =?us-ascii?Q?0FQ1AKuavkmZ2SY5jMOsr8/1uIfMqaQnZwAM6CEqZox2gpQ0gu8/6tyKPAXz?= =?us-ascii?Q?1U8zBXyXR7tyzJiHY3DX4Rq3EowWkqTBRGLNmDFbkUe1+Bt6MDZOY2nV7aKz?= =?us-ascii?Q?jXOFYRUx0CSezHO+l9wVvNUkM2stbgEK+9/kxtbWgt242EgQXbyaChx+L9YA?= =?us-ascii?Q?+YDaPSqb7SvcXxznw2po5Fl5VEbCBiw9jhak0bVIa9/suv2dguMIwbWh2blU?= =?us-ascii?Q?IIJcPZGNDahhSypbTERBkJtNO50afIJ92+0v4RZ3XGVUafjmGXN929m1KEXU?= =?us-ascii?Q?R/gf70kqBHedYKGJ9LxnockgSweyisrnkq2y+xzsOgXwQ1lq9jmk3cP0uaZ+?= =?us-ascii?Q?Un1qxrOLtxyKDo+ASoC9/l79JADyutQXuPyA+yEBAwddWdMco06Y9xoXZ/eL?= =?us-ascii?Q?mrVo3CL7YsU2JCkBwNYe15xPjRWgM8rKIJRikyfyo4b8SNvUJBkbNLUaKZHS?= =?us-ascii?Q?EMT2N+mcIU502ENz5wibsJWLYhRMcRE0O53YaPRyHWHvjgv+PEShvBorCQD8?= =?us-ascii?Q?6bzucQohBfcG0HPfUjuYCl32l8giXUYVnBxFuNQYP+zYtXKK4d7+PNxsctvA?= =?us-ascii?Q?PUc0ZPJG/xu14tSaHyQQjtUTB6ashjzCxM2mnojpWNppi7qss4r//8nxbVl+?= =?us-ascii?Q?8HsGlKkJnyA/0quZhVSNpUpnnuGpvCOzjxYyM0aEnLb/d86JBQPPFqh+Ur3m?= =?us-ascii?Q?Ax3hN/1PyedCJd4P9X/4IgMdo+9N+26rq9flxrJ90d5dyjGFAagMOKwY1HOJ?= =?us-ascii?Q?l5eUn3xOcSYAYLJ6SOMZQwQuhkq8HrkP75Pl3QYCBd9ggySgFocv1XZ5pr5p?= =?us-ascii?Q?vbYq8cwzfY5ZKmrd4z9nF3sWxfb1T4tstbcQGa3ihshuZ+4EJa7pATzbNFfj?= =?us-ascii?Q?SCk8WGhPm0Wj42Vq48LIsHIt2/itP/hHX+CPCTt7HZnTnlqeHc6p1UObOCk3?= =?us-ascii?Q?YRUwJQ9ZgfAzYZ1269w=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3ca1bb44-dbe2-401c-5feb-08dad3b24b32 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Dec 2022 15:39:54.6671 (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: m6d6juI8IZxvKHUt4WkXEUORuRsYcEdfFbHOSfYlbR8wyoMYmTsGQptsUOEgT7j3 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR12MB7362 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Thu, Dec 01, 2022 at 09:38:10AM -0600, Bob Pearson wrote: > Further, looking at ipoib as an example, it builds sge lists using the lkey from get_dma_mr() > and sets the sge->addr to a kernel virtual memory address after previously calling > ib_dma_map_single() so the addresses are mapped for dma access and visible before use. > They are unmapped after the read/write operation completes. What is the point of kmapping > the address after dma mapping them? Because not everything is ipoib, and things like block will map sgls with struct pages, not kva. Jason