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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?lFMizaSWcYI7/BJ09aJJZGwZ+GmF29bQnl13kq7tNwFpz6URWHx1V7KAFGhl?= =?us-ascii?Q?ljSW6jjBojMO7OTaSZzrIEU9i04K9VaksuA85JIU1I0VB+Ogpxvwdw5fwl6D?= =?us-ascii?Q?M6EQs4DM+tm38MDs4ONaFll6s5muub4WBMerXrEah2KYRmZmTCktcxFTOXvr?= =?us-ascii?Q?eCExAMa1RhHU7hPaI8YE8zOYg7fxIqtaTAqLX/sw6JR2cmDGnRKrLT2F8svL?= =?us-ascii?Q?TVBD4KhFCb6/VSLMF1p1Eeoxa0ilzyI5eGerfRrw1F5hBLl+sSnZYJYbkk1d?= =?us-ascii?Q?Rz710xeEWPkdh3x9KwG6m2ziHAfjMkmNTgLq3PBSmPdXh+oFdIQ5+tCpnvPs?= =?us-ascii?Q?4C7AxCvHWIU1BJJ5V4AgQfL4ebsNEPw7bWSFiieSC+oikdd2u/fw0jEwr8um?= =?us-ascii?Q?ex4iyQcRFuRWk0RVxla1bcUDmkf0HtbzQUxm7jGgQbT7rNreYrF9X/jYmHnN?= =?us-ascii?Q?MQvq6dCXdnwG8m1u1Qr4rnPykKAQ3RGJN2kmwIKO/LoLngog3aE9lWqzIBob?= =?us-ascii?Q?oBRZc2U/P038t9oa27LrmGWhUjTwGb7NSctzIN7fMMOnTCMxeHd7ErZdMLBn?= =?us-ascii?Q?DK0r0Afy+/51/svy9i5V5Oum73ja5ZJ71nMXLP3At5H8J+0XGU4R/S9S97Gl?= =?us-ascii?Q?B3NiZslvA12oTlMiqpqYxtr1+cquMocHA4KBDTgG8wrCX3WfplySHm3Nw0yH?= =?us-ascii?Q?/rHVAwBULKaufIBAKerZREjHIo/6rrSqBEUWbYfSo0cvdXlgC+SjODxegEIW?= =?us-ascii?Q?HXvR0g4XyPgranLCcC+xG/lTcGQQepaBbwQljJ1P4nYZEgStfSrJ6SQ1iVJu?= =?us-ascii?Q?ol7nra50EdqhYAkj7EA5SW/niKmTa0oyWVPbFoD7lhZxpe6GbQLyYe3yiEFk?= =?us-ascii?Q?l2opkwEQk5HJlGKSDC/tZfBDDde10QS1HLYgCANEjtaspE5PSKSoWsdKadUD?= =?us-ascii?Q?i0RJqLMMlYURh8d8vXJ85xrM+mmJdTfG3NJPPS6WMKKi66JzyQNlwStObnn8?= =?us-ascii?Q?WWd5e99a85engY5PQcO+uG6b1TgeA2i8Ky7vB/eYppJXowv0mrJniIsHxzbp?= =?us-ascii?Q?Q/BRsBS9p3R7abAJm4Np07s7J/5LeIgvtWq6nutfprkqP0+aCoxe+wRW6p7T?= =?us-ascii?Q?iOnRacmMCXkRjNuFP7aaW8IAYMJAW99xXbSKa5t2smgRAaDOKYFLTXMzciQ9?= =?us-ascii?Q?bPzfT7ODZha1E9kayhDy5T32sxX6l2os+gsLLCduaMfvKox42+aP8lwsaT+4?= =?us-ascii?Q?gNHHeLlGVfrk8/Xq5N/gS1LQtVOxKn1b7DfnPPVhFhaxCohvvGEH2HU8mBt4?= =?us-ascii?Q?NiJ0HR7iLoFklHwbBx3HfCZ4wulSeT10OBaxw7ncsXF/y6ONNY7ympmEeWRD?= =?us-ascii?Q?q4yQ9m2f720DDZIe1a1yA3hWawLxjtQtomRsVoVtjclg3Xas5fSYhQzNNxNj?= =?us-ascii?Q?QbpUH8Pm5SAH0oXNtE58mnNsKLDqroAuGXDFQCI6eqbfwzNlkKtZo6tg8Ybi?= =?us-ascii?Q?0pGLepFoUydTwj4pcXOD2tAVnxRSz8Q/nqPkXlK137hKhvB5XPJOg7hLolS1?= =?us-ascii?Q?6vqihwKkbUR7QfNoUNF5QPy56opyZdcSywoqP06bVquoAW1cmaUmyvKDd9Nm?= =?us-ascii?Q?fmyPELj3LvNDOKyxtz1NAsx4irF5KfzBaxHEw0q6iXuffrLyB1nqqvC1dl9E?= =?us-ascii?Q?qsuEf2cRqK82XfIfXy69RzOfEB8bSw3RxKQnWEdMPZ7lekWQ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6f8e11e0-834e-4e7f-a8da-08dec19c2c69 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Jun 2026 18:16:03.9301 (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: 737+n6p+HB7YSrChpSmRWp6mY7EOsKMfDEzu5bTjV+w1oq5YTtESVsBxl4GTg3jv X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB8601 On Tue, May 26, 2026 at 01:46:53PM +0800, Maoyi Xie wrote: > setup_root_hem() reads the first entry of head->root and checks > the returned pointer against NULL: > > root_hem = list_first_entry(&head->root, > struct hns_roce_hem_item, list); > if (!root_hem) > return -ENOMEM; > > list_first_entry() never returns NULL. On an empty list it returns > container_of(head, ..., list), a non-NULL garbage pointer that > aliases the head. So the check is dead. > > The only caller adds an entry to head.root right before invoking > setup_root_hem(): > > list_add(&root_hem->list, &head.root); > ret = setup_root_hem(..., &head, ...); > > So head.root is guaranteed non-empty on entry. Drop the check. > > Suggested-by: Jason Gunthorpe > Signed-off-by: Maoyi Xie > --- > v2: drop the check entirely per Jason's review, instead of > converting to list_first_entry_or_null() as in v1. > v1: https://lore.kernel.org/r/20260521132045.3430906-1-maoyixie.tju@gmail.com > > drivers/infiniband/hw/hns/hns_roce_hem.c | 2 -- > 1 file changed, 2 deletions(-) Applied to for-next, thanks Jason