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BUG: KCSAN: data-race in rwsem_down_write_slowpath / rwsem_down_write_slowpath

write to 0xffffc90003f43b80 of 1 bytes by task 6037 on cpu 0:
 rwsem_try_write_lock kernel/locking/rwsem.c:653 [inline]
 rwsem_down_write_slowpath+0x3c9/0xa90 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:1118 [inline]
 ib_setup_port_attrs+0xe89/0x1400 drivers/infiniband/core/sysfs.c:1394
 add_one_compat_dev+0x297/0x390 drivers/infiniband/core/device.c:977
 add_compat_devs drivers/infiniband/core/device.c:1035 [inline]
 enable_device_and_get+0x1cd/0x260 drivers/infiniband/core/device.c:1346
 ib_register_device+0xb41/0xcc0 drivers/infiniband/core/device.c:1459
 rxe_register_device+0x175/0x190 drivers/infiniband/sw/rxe/rxe_verbs.c:1556
 rxe_add+0x8c7/0x8e0 drivers/infiniband/sw/rxe/rxe.c:212
 rxe_net_add+0x62/0xb0 drivers/infiniband/sw/rxe/rxe_net.c:618
 rxe_newlink+0xc6/0x180 drivers/infiniband/sw/rxe/rxe.c:234
 nldev_newlink+0x3a8/0x430 drivers/infiniband/core/nldev.c:1797
 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline]
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0x477/0x5b0 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x5c0/0x690 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x5c8/0x6f0 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x5af/0x600 net/socket.c:2592
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2681
 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/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc90003f43b80 of 1 bytes by task 31341 on cpu 1:
 rwsem_down_write_slowpath+0x43d/0xa90 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_by_name_ns+0x5c/0xf0 fs/kernfs/dir.c:1717
 kernfs_remove_by_name include/linux/kernfs.h:633 [inline]
 remove_files fs/sysfs/group.c:28 [inline]
 sysfs_remove_group+0xa5/0x170 fs/sysfs/group.c:328
 sysfs_remove_groups+0x3a/0x80 fs/sysfs/group.c:352
 __kobject_del+0x4b/0x190 lib/kobject.c:595
 kobject_del+0x2e/0x50 lib/kobject.c:627
 ext4_unregister_sysfs+0x75/0x80 fs/ext4/sysfs.c:647
 ext4_put_super+0x4c/0x7d0 fs/ext4/super.c:1297
 generic_shutdown_super+0xee/0x220 fs/super.c:646
 kill_block_super+0x2a/0x70 fs/super.c:1725
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7459
 deactivate_locked_super+0x75/0x1c0 fs/super.c:476
 deactivate_super+0x97/0xa0 fs/super.c:509
 cleanup_mnt+0x2bb/0x330 fs/namespace.c:1312
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1319
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
 exit_to_user_mode_loop+0x1f4/0x6f0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x249/0x370 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 31341 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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EXT4-fs (loop4): unmounting filesystem 00000000-0000-0000-0000-000000000000.