======================================================
WARNING: possible circular locking dependency detected
5.15.156-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/5670 is trying to acquire lock:
ffff0000c9120c28 ((work_completion)(&hdev->bg_scan_update)){+.+.}-{0:0}, at: __flush_work+0xd0/0x1c0 kernel/workqueue.c:3090

but task is already holding lock:
ffff800016cb8d88 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x250/0x750 net/rfkill/core.c:1266

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (rfkill_global_mutex){+.+.}-{3:3}:
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       rfkill_register+0x44/0x7a4 net/rfkill/core.c:1045
       hci_register_dev+0x3e0/0x880 net/bluetooth/hci_core.c:3960
       __vhci_create_device drivers/bluetooth/hci_vhci.c:129 [inline]
       vhci_create_device+0x2c4/0x568 drivers/bluetooth/hci_vhci.c:153
       vhci_get_user drivers/bluetooth/hci_vhci.c:210 [inline]
       vhci_write+0x318/0x3b8 drivers/bluetooth/hci_vhci.c:290
       call_write_iter include/linux/fs.h:2172 [inline]
       new_sync_write fs/read_write.c:507 [inline]
       vfs_write+0x87c/0xb3c fs/read_write.c:594
       ksys_write+0x15c/0x26c fs/read_write.c:647
       __do_sys_write fs/read_write.c:659 [inline]
       __se_sys_write fs/read_write.c:656 [inline]
       __arm64_sys_write+0x7c/0x90 fs/read_write.c:656
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #3 (&data->open_mutex){+.+.}-{3:3}:
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       vhci_send_frame+0x8c/0x10c drivers/bluetooth/hci_vhci.c:71
       hci_send_frame+0x194/0x2f0 net/bluetooth/hci_core.c:4252
       hci_sched_acl_pkt net/bluetooth/hci_core.c:4777 [inline]
       hci_sched_acl net/bluetooth/hci_core.c:4862 [inline]
       hci_tx_work+0x8d8/0x157c net/bluetooth/hci_core.c:4933
       process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
       worker_thread+0x910/0x1034 kernel/workqueue.c:2457
       kthread+0x37c/0x45c kernel/kthread.c:334
       ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

-> #2 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}:
       __flush_work+0xf8/0x1c0 kernel/workqueue.c:3090
       flush_work+0x24/0x38 kernel/workqueue.c:3115
       hci_dev_do_close+0x16c/0x1060 net/bluetooth/hci_core.c:1756
       hci_unregister_dev+0x228/0x4b4 net/bluetooth/hci_core.c:4036
       vhci_release+0x74/0xc4 drivers/bluetooth/hci_vhci.c:345
       __fput+0x30c/0x7f0 fs/file_table.c:280
       ____fput+0x20/0x30 fs/file_table.c:308
       task_work_run+0x130/0x1e4 kernel/task_work.c:164
       exit_task_work include/linux/task_work.h:32 [inline]
       do_exit+0x670/0x20bc kernel/exit.c:872
       do_group_exit+0x110/0x268 kernel/exit.c:994
       get_signal+0x634/0x1550 kernel/signal.c:2889
       do_signal arch/arm64/kernel/signal.c:890 [inline]
       do_notify_resume+0x3d0/0x32b8 arch/arm64/kernel/signal.c:943
       prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline]
       exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline]
       el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626