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BUG: KCSAN: data-race in rwsem_down_write_slowpath / rwsem_down_write_slowpath

write to 0xffffc90000e8b448 of 1 bytes by task 13660 on cpu 0:
 rwsem_try_write_lock kernel/locking/rwsem.c:676 [inline]
 rwsem_down_write_slowpath+0x3dd/0xac0 kernel/locking/rwsem.c:1189
 __down_write_common kernel/locking/rwsem.c:1347 [inline]
 __down_write kernel/locking/rwsem.c:1356 [inline]
 down_write+0xab/0xc0 kernel/locking/rwsem.c:1626
 kernfs_add_one+0x5a/0x280 fs/kernfs/dir.c:826
 __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:1118 [inline]
 ib_setup_port_attrs+0xe87/0x1400 drivers/infiniband/core/sysfs.c:1394
 add_one_compat_dev+0x297/0x390 drivers/infiniband/core/device.c:978
 rdma_dev_init_net+0x1b9/0x240 drivers/infiniband/core/device.c:1194
 ops_init+0x22a/0x2e0 net/core/net_namespace.c:137
 setup_net+0x9f/0x230 net/core/net_namespace.c:446
 copy_net_ns+0x310/0x450 net/core/net_namespace.c:579
 create_new_namespaces+0x20e/0x440 kernel/nsproxy.c:132
 unshare_nsproxy_namespaces+0x115/0x150 kernel/nsproxy.c:234
 ksys_unshare+0x402/0x700 kernel/fork.c:3240
 __do_sys_unshare kernel/fork.c:3311 [inline]
 __se_sys_unshare kernel/fork.c:3309 [inline]
 __x64_sys_unshare+0x1f/0x30 kernel/fork.c:3309
 x64_sys_call+0x1cef/0x3020 arch/x86/include/generated/asm/syscalls_64.h:273
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc90000e8b448 of 1 bytes by task 13658 on cpu 1:
 rwsem_down_write_slowpath+0x44f/0xac0 kernel/locking/rwsem.c:1207
 __down_write_common kernel/locking/rwsem.c:1347 [inline]
 __down_write kernel/locking/rwsem.c:1356 [inline]
 down_write+0xab/0xc0 kernel/locking/rwsem.c:1626
 kernfs_remove_by_name_ns+0x6b/0x110 fs/kernfs/dir.c:1793
 kernfs_remove_by_name include/linux/kernfs.h:639 [inline]
 sysfs_unmerge_group+0x80/0xb0 fs/sysfs/group.c:408
 dpm_sysfs_remove+0x72/0x90 drivers/base/power/sysfs.c:833
 device_del+0x13d/0x790 drivers/base/core.c:3855
 netdev_unregister_kobject+0x24d/0x270 net/core/net-sysfs.c:2314
 unregister_netdevice_many_notify+0x128b/0x1650 net/core/dev.c:12499
 unregister_netdevice_many net/core/dev.c:12527 [inline]
 unregister_netdevice_queue+0x1cd/0x200 net/core/dev.c:12337
 unregister_netdevice include/linux/netdevice.h:3427 [inline]
 nsim_destroy+0x122/0x560 drivers/net/netdevsim/netdev.c:1190
 __nsim_dev_port_del+0xd2/0x140 drivers/net/netdevsim/dev.c:1547
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1561 [inline]
 nsim_dev_reload_destroy+0x1a3/0x2c0 drivers/net/netdevsim/dev.c:1785
 nsim_dev_reload_down+0x67/0x80 drivers/net/netdevsim/dev.c:1038
 devlink_reload+0xad/0x590 net/devlink/dev.c:462
 devlink_nl_reload_doit+0x503/0x960 net/devlink/dev.c:585
 genl_family_rcv_msg_doit+0x187/0x1f0 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x432/0x470 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x5a8/0x680 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x5c8/0x6f0 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 ____sys_sendmsg+0x563/0x5b0 net/socket.c:2698
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2752
 __sys_sendmsg net/socket.c:2784 [inline]
 __do_sys_sendmsg net/socket.c:2789 [inline]
 __se_sys_sendmsg net/socket.c:2787 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2787
 x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 13658 Comm: syz.2.2936 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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