INFO: task syz.4.79:4378 blocked for more than 143 seconds.
      Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.79        state:D stack:    0 pid: 4378 ppid:  4021 flags:0x00000001
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6373
 schedule+0x11c/0x1c8 kernel/sched/core.c:6456
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6515
 __mutex_lock_common+0xba0/0x2154 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
 __fdget_pos+0x128/0x170 fs/file.c:1084
 fdget_pos include/linux/file.h:75 [inline]
 ksys_read+0x8c/0x26c fs/read_write.c:614
 __do_sys_read fs/read_write.c:633 [inline]
 __se_sys_read fs/read_write.c:631 [inline]
 __arm64_sys_read+0x7c/0x90 fs/read_write.c:631
 __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

Showing all locks held in the system:
2 locks held by kworker/1:0/21:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001bd07c00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
1 lock held by khungtaskd/27:
 #0: ffff800014c917e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
3 locks held by kworker/1:2/2427:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff8000267d7c00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000d051c240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x274/0x33c4 drivers/net/netdevsim/fib.c:1478
2 locks held by getty/3780:
 #0: ffff0000d2f5a098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001d62b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
3 locks held by kworker/u4:9/4198:
4 locks held by kworker/u4:10/4211:
3 locks held by syz.4.79/4370:
1 lock held by syz.4.79/4378:
 #0: ffff0000dac84d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x128/0x170 fs/file.c:1084
3 locks held by syz.2.183/4829:
1 lock held by syz.2.183/4831:
 #0: ffff0000d532a370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x128/0x170 fs/file.c:1084
3 locks held by syz-executor/4857:
 #0: ffff0000d590cff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x64/0x1060 net/bluetooth/hci_core.c:1737
 #1: ffff0000d590c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x338/0x1060 net/bluetooth/hci_core.c:1782
 #2: ffff800016d361a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline]
 #2: ffff800016d361a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622
3 locks held by kworker/0:13/5106:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800020d17c00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000d8f9a240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x274/0x33c4 drivers/net/netdevsim/fib.c:1478
2 locks held by syz-executor/5171:
 #0: ffff0000daa20ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x64/0x1060 net/bluetooth/hci_core.c:1737
 #1: ffff0000daa20078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x338/0x1060 net/bluetooth/hci_core.c:1782
2 locks held by syz-executor/5464:
3 locks held by syz-executor/5467:
 #0: ffff0000d8894ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x64/0x1060 net/bluetooth/hci_core.c:1737
 #1: ffff0000d8894078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x338/0x1060 net/bluetooth/hci_core.c:1782
 #2: ffff800016d361a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline]
 #2: ffff800016d361a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622
1 lock held by syz-executor/5686:
 #0: ffff800014c95cf0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x54/0x4b0 kernel/rcu/tree.c:4039

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