==================================================================
BUG: KCSAN: data-race in rwsem_down_write_slowpath / rwsem_down_write_slowpath

write to 0xffffc900001439f0 of 1 bytes by task 9610 on cpu 1:
 rwsem_try_write_lock kernel/locking/rwsem.c:653 [inline]
 rwsem_down_write_slowpath+0x3eb/0xa80 kernel/locking/rwsem.c:1159
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0xab/0xc0 kernel/locking/rwsem.c:1591
 kernfs_add_one+0x5a/0x280 fs/kernfs/dir.c:796
 __kernfs_create_file+0x145/0x180 fs/kernfs/file.c:1086
 sysfs_add_file_mode_ns+0x132/0x1b0 fs/sysfs/file.c:313
 create_files fs/sysfs/group.c:82 [inline]
 internal_create_group+0x441/0x9e0 fs/sysfs/group.c:189
 internal_create_groups fs/sysfs/group.c:229 [inline]
 sysfs_create_groups+0x3f/0xf0 fs/sysfs/group.c:255
 setup_gid_attrs drivers/infiniband/core/sysfs.c:1162 [inline]
 ib_setup_port_attrs+0xed2/0x14c0 drivers/infiniband/core/sysfs.c:1439
 add_one_compat_dev+0x297/0x390 drivers/infiniband/core/device.c:1005
 rdma_dev_init_net+0x1b9/0x240 drivers/infiniband/core/device.c:1221
 ops_init+0x22a/0x2e0 net/core/net_namespace.c:137
 setup_net+0x9f/0x230 net/core/net_namespace.c:446
 copy_net_ns+0x308/0x450 net/core/net_namespace.c:581
 create_new_namespaces+0x20e/0x440 kernel/nsproxy.c:130
 copy_namespaces+0x1ad/0x210 kernel/nsproxy.c:195
 copy_process+0xce5/0x1f10 kernel/fork.c:2224
 kernel_clone+0x16b/0x5b0 kernel/fork.c:2651
 __do_sys_clone kernel/fork.c:2792 [inline]
 __se_sys_clone kernel/fork.c:2776 [inline]
 __x64_sys_clone+0x143/0x180 kernel/fork.c:2776
 x64_sys_call+0x12d0/0x3000 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc900001439f0 of 1 bytes by task 37 on cpu 0:
 rwsem_down_write_slowpath+0x45e/0xa80 kernel/locking/rwsem.c:1177
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0xab/0xc0 kernel/locking/rwsem.c:1591
 kernfs_remove+0x50/0x70 fs/kernfs/dir.c:1554
 sysfs_remove_dir+0x7d/0xa0 fs/sysfs/dir.c:101
 __kobject_del+0x97/0x190 lib/kobject.c:604
 kobject_cleanup lib/kobject.c:680 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x124/0x180 lib/kobject.c:737
 net_rx_queue_update_kobjects+0x49b/0x540 net/core/net-sysfs.c:1338
 remove_queue_kobjects net/core/net-sysfs.c:2169 [inline]
 netdev_unregister_kobject+0xbf/0x270 net/core/net-sysfs.c:2325
 unregister_netdevice_many_notify+0x1346/0x1710 net/core/dev.c:12431
 unregister_netdevice_many+0x19/0x20 net/core/dev.c:12459
 ops_exit_rtnl_list net/core/net_namespace.c:187 [inline]
 ops_undo_list+0x21d/0x420 net/core/net_namespace.c:248
 cleanup_net+0x31c/0x550 net/core/net_namespace.c:696
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0x4cd/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x6bc/0x8b0 kernel/workqueue.c:3421
 kthread+0x488/0x510 kernel/kthread.c:463
 ret_from_fork+0x148/0x280 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 37 Comm: kworker/u8:2 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: netns cleanup_net
==================================================================