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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?TlR71DxhkLpdfo4Z9Ecs5emnSaWZjJp7mpFuZxZHK6vZoyTKiH2W0FOXWT9E?= =?us-ascii?Q?S5XHo10WkS5AmScXPUE/zEaKi9tath6QohlI6oSDwo2goq8qlNZ2TKYmaR+9?= =?us-ascii?Q?nwocLa/3GZn1JpQzwfSRtCkq6uC4OuNTH11mTQjwo5w/L1zNRbpE6Iw5Gn75?= =?us-ascii?Q?xEPWoS4Zy9BnJMQ88SUuSbFgX/BP0OqQjsuY73Lowl8/5tAv5S7PQn7k6MGo?= =?us-ascii?Q?J5JDZL/T9XSTnwmSZ5y05vv7Ad0nl9iA5ivw+q+RSMWl+zrpRiikjxlPklDM?= =?us-ascii?Q?U/eh07RkYkfqzmSmL+wm8h64J3QAwweieeIuV0hVVx+lCGWuM6hYJNcIgxWm?= =?us-ascii?Q?JvJFnccvIC73cghpEc2mVLjrlaJsqqa70LVtXd4irRc9Re+rW0T3pmOxetZq?= =?us-ascii?Q?o5OW9arIIKYKZb40BxhBo9cQjhbBU+bRgUEh/lM+eYRTINRU+ExIbMNC6J5h?= =?us-ascii?Q?BLIwy1bZIvYFHYV1vSFyjZTjQfpth1kP55j4bLclXE262rt11bll2wP+MinG?= =?us-ascii?Q?oQ2hdqoEKOTWFgBplvZpePZkhzwtbefVgBfIeMaAXLci2nbr6U5auhaqq3Gf?= =?us-ascii?Q?LGo+6dA/PBzwfVlmCD8Rf3qyWV4eIEmPqeti3nRd6B15dwgv1GHLLyCaGfyb?= =?us-ascii?Q?WBEk3LABRBCFjgIG5JZEZG70lRRFebaORprcV9HjB1f31EM657u1HeXjOKja?= =?us-ascii?Q?BclfSUkhuNPVHqn/97mbnNxbJ7P+gt74mPIjnNmcGjBNLGUCx7E8QvM08dqw?= =?us-ascii?Q?NnP+xrtf38UrmotW4jK1feuhMY4nFsK0zn0Lxf+4uLNhtPICWftPztcJv9QE?= =?us-ascii?Q?AuqmuDRVuXBEtG9MdML6eQl9HYH8zLpgw/pV5Ut6XvClznQsUTcHgNzb/fQv?= =?us-ascii?Q?ciWerNBi3Vv78I4LO1n1wwTFL7yWCCqh/G+sEGpjSte4g2JffAwDnLHKynC9?= =?us-ascii?Q?kquT8DxkoMOUn5Qc2NQDhgltnR48SAbzQh8DwzfmHjTJlrGCHYCLzK1cX1uv?= =?us-ascii?Q?Q7EjaC3U6vBG3zUzE3nF1pV5GyoWuv4hgfHO/hcuFGkCw7v/JUixu5J4hKOC?= =?us-ascii?Q?EsRQnX6Tf6kla/Zl1m30uCcCsyy+8sMNHrqR/tJB23mp2B+ojQYShuuJ+L3H?= =?us-ascii?Q?ALJp0nJ6TQrnOnpEL6pwxPnPA+yz7Ztz9Ny4HTb8Pn2UOTBsVwWel+Vvb9ZU?= =?us-ascii?Q?CKfLtIEQ2DZf3rKeizJ759illanR9Ch5hpMzYLhdteFNb8PeHtPxowLvuERA?= =?us-ascii?Q?iCtcw3T0p75cgxiHNol+lxjbA2d2u/4T2vtcYUEfVQPLf/VBwGaHcons0ZcE?= =?us-ascii?Q?N/1d+NBFQxGwhY+SDDVIOVY/Pz4lKXugLtMXDEO825jbXtNE3QSW6cRQpxdq?= =?us-ascii?Q?/TLu/mCfCdkU3VBXxJEp8aI7mYIPTvD5lBp+QKwBPjKeJpY39sDgMCcmFPs9?= =?us-ascii?Q?qcYi2aLo0cKdIi9yVWGY+KhgGX3ma5UDtekWJ0Ik4PVMeE7yo8JG2NX7Mn9b?= =?us-ascii?Q?FxZvR4DOlrKt1zzssJcW0nkOx8upkkBlEsHsCSzP5CwRkSChb+5PaPgmC9fT?= =?us-ascii?Q?kEoRfmoNquU0mMvHqGcry/MXJ0y9lt1sfkgEX5iQ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4318828a-ceaf-4a83-32a7-08dd57716225 X-MS-Exchange-CrossTenant-AuthSource: MW6PR12MB8663.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Feb 2025 20:57:44.7936 (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: G4PEfeRvzGRAzwD/z02jFcqx8n0DFJ6uXpDmhUASVxxxTFxyawn5RtyOxrGlyr31 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB6749 On Wed, Feb 26, 2025 at 03:54:13PM +0200, Leon Romanovsky wrote: > From: Maher Sanalla > > Currently, the IB uverbs API calls uobj_get_uobj_read(), which in turn > uses the rdma_lookup_get_uobject() helper to retrieve user objects. > In case of failure, uobj_get_uobj_read() returns NULL, overriding the > error code from rdma_lookup_get_uobject(). The IB uverbs API then > translates this NULL to -EINVAL, masking the actual error and > complicating debugging. For example, applications calling ibv_modify_qp > that fails with EBUSY when retrieving the QP uobject will see the > overridden error code EINVAL instead, masking the actual error. I still didn't see an answer to the question of why userspace would hit an EBUSY down that path in a way we need to care about? That is doing dumb racing thread stuff that nothing should be doing.. > Furthermore, based on rdma-core commit: > "2a22f1ced5f3 ("Merge pull request #1568 from jakemoroni/master")" > Kernel's IB uverbs return values are either ignored and passed on as is > to application or overridden with other errnos in a few cases. I don't understand this sentence Is this the defence of why it is safe to do this? But if the rdma-core overrides them what is the point of forwarding? Jason