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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?FnRj9X0OdvEmEzTnIoFNegwbuxLCrAS90WZ4Sx/cE+fy99fAqvFw4ZI+tVu4?= =?us-ascii?Q?2bH9slGqFs7QzHN8wD0BJGd2oh0A9mAKE46qb8z1RYUoBRsUAqwtBwUgeoCg?= =?us-ascii?Q?IHYlMZVNtiW3O7uUILBWq6KWHjomr8AqN8XXbCbMRlzekrXW6gUavRliYWs2?= =?us-ascii?Q?pz/ivHan8TeoMRS0PE9seA+6ARQ+cruhIgkiwDJULUIZth+wio0SwVsRYIsH?= =?us-ascii?Q?CJF1uAd7IXiF+PBpkYa/sgSlKbb9rqfu+99xLXJE38QcAt0Yt63D463OAWga?= =?us-ascii?Q?qvnAk76fTHQ43GxypstlNXKf9AXoe28Sa/tc8WtZvQK6+xtjoal3fnfHAXVb?= =?us-ascii?Q?kOOo1oR1yAT+pcjLXx+NaDdoJ9lBi05HJP4wsoi/TBsTIYP8KwBdWgNMB2KO?= =?us-ascii?Q?rgZQlST0BeDoyAOcEA3xY7/lEnzsknT6NlDbS83n4LuLnLmpZ49GB3OcaL40?= =?us-ascii?Q?+QR3EQ2WwdMnDTLpXhGa5OJ+fEJZguK+5bhUASfeg6dqm6kUVcMkiELWsDZT?= =?us-ascii?Q?IEj9OMuFPZ102pLHNYDzLx3RlZ1bkR76H5OHXbgGXBNuidakjx5FR6Z6SpCU?= =?us-ascii?Q?6LWEPT3PIQR9bTkMwoTO0mWVnHt36RL5cao61DOHUU69M5EZ9OeKOwhRvyzG?= =?us-ascii?Q?2E32P/lhZYrF+qIAw5e98lAztbhTFq4MK3jglD/zSLJgtU/GNkY5rZ6nEcpg?= =?us-ascii?Q?3bg9YFb1CkqCIBfZs1EOrOqm6DOKf+kpYMX1OCf5WtSrb2p8Is90ot+1fRmx?= =?us-ascii?Q?gQR0ymxmzXjofHtAwU4t1gUzCYXWzaMt+FJSNEwGPRbH9G4gIs96m9h0R87z?= =?us-ascii?Q?85Ihq1+68+sn6bMC16M+mXWlIPj6yzlzpi32gPmxQ+gVC+eMaD2AVA7iJ3UZ?= =?us-ascii?Q?d+lVp+/3Wg3DYdoVAUtjfZe2c64HbT3R02N4WqafGq1z6RetfiwKjyvU5vNI?= =?us-ascii?Q?f9HBiZfDfx+AyjSPx1Z4PuUEhHd/s3INORcgPlO2nEdcuYK7NQNm5BlV45Z5?= =?us-ascii?Q?09aEYa5ZRiVjRXADDqWIo5JTU/8nIHxTj8GoiUQCRPTQhXI9sDpBru29dmqe?= =?us-ascii?Q?IYMc9zqMBj80Z3jXLEqRuaNOHgAaKBW2KgV1eCMzAKKLffqeR7DUpDX8j4pn?= =?us-ascii?Q?ZNosi7bbtWKZU6qzrQIkTQVgnAQlKBLAZhcfxF9/JPDhv0oWEcUcDtXbhlps?= =?us-ascii?Q?JlrSZhHJTEIrK5uuy9i+GzL9bEZ/YKQ3V3bf38kKnHlF8LUtir6K5N8VGApZ?= =?us-ascii?Q?JgQBm9YBZNLacMk/2phi1vQHNfHAHpYJ7Sbnwlw/QK/lUgzxuOD7r4g6X4aC?= =?us-ascii?Q?8v8b52ZowneekVvPEGlQoEs9nVzbPq0L0WOHQXY4IBqTveycPkOi7ACwCxmi?= =?us-ascii?Q?y8LZ/ISfCHLIDP9IHUQgVTDIQOsRrHQlJ4BCtn5kERdorze/a5uaI1/wlq/0?= =?us-ascii?Q?Jddrjcp3HY69/qEBeL3ULlOnUtd0JY+tUVbkYhERa+N4LB92bPDH3YnhlpmJ?= =?us-ascii?Q?9wMLJwDMwS42QQsy2rr1+4A72Qf3R8IATSpaPRdoOw2OJEcIw5LZItfphBDE?= =?us-ascii?Q?U+o2tY+Z0VORR89nzAWqkBaJUK/9VtVYEJjPU+tw?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e447b122-0db6-436a-fd78-08dd737c83f9 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Apr 2025 13:27:58.5573 (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: whwrYd5Rwo5EbmIavWNVUKueoeeiNuHsJBqAQlqKscKNRCQ1UszviLOTGa39aDWV X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6417 On Wed, Apr 02, 2025 at 12:05:36PM +0800, Junxian Huang wrote: > > > On 2025/4/2 0:39, Jason Gunthorpe wrote: > > On Thu, Mar 27, 2025 at 07:47:24PM +0800, Junxian Huang wrote: > >> @@ -763,7 +763,7 @@ static int hns_roce_register_device(struct hns_roce_dev *hr_dev) > >> if (ret) > >> return ret; > >> } > >> - dma_set_max_seg_size(dev, UINT_MAX); > >> + dma_set_max_seg_size(dev, SZ_2G); > > > > Are you sure? What do you think this does in the RDMA stack? > > > > This is the maximum DMA segment size when mapping ULP's scatter/gather > list to DMA address, right? Yes, but only for ib_sge But I think there are other possible problems if your HW cannot implement the full ib_sge :\ Jason