INFO: task syz.4.1626:11033 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.1626      state:D stack:25768 pid:11033 ppid:7698   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 schedule+0xbd/0x170 kernel/sched/core.c:6775
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6834
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747
 __fdget_pos+0x2a3/0x330 fs/file.c:1040
 fdget_pos include/linux/file.h:75 [inline]
 ksys_write+0x7b/0x260 fs/read_write.c:628
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f811cd9e559
RSP: 002b:00007f811dbe6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f811d026090 RCX: 00007f811cd9e559
RDX: 0000000000000003 RSI: 0000200000000200 RDI: 0000000000000003
RBP: 00007f811ce35ab8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f811d026128 R14: 00007f811d026090 R15: 00007ffc4c35a048
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/0:0/8:
3 locks held by kworker/0:1/9:
 #0: ffff888018872d38 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #0: ffff888018872d38 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #1: ffffc900000e7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #1: ffffc900000e7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #2: ffff8880b8c3c258 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
4 locks held by kworker/u4:0/11:
 #0: ffff888140045138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #0: ffff888140045138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #1: ffffc90000107d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #1: ffffc90000107d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #2: ffffffff8f1c5810 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x140/0xb00 net/core/net_namespace.c:610
 #3: ffffffff8df37ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
 #3: ffffffff8df37ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
1 lock held by khungtaskd/28:
 #0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6669
2 locks held by kworker/u4:4/55:
4 locks held by kworker/u4:5/76:
3 locks held by kworker/u4:7/1099:
3 locks held by kworker/u4:8/2959:
2 locks held by kworker/u4:9/2995:
 #0: ffff8880202fe938 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #0: ffff8880202fe938 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #1: ffffc9000ba3fd00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #1: ffffc9000ba3fd00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
2 locks held by kworker/u4:10/5004:
1 lock held by klogd/5129:
2 locks held by kworker/0:4/5845:
5 locks held by kworker/1:5/5879:
 #0: ffff8880b8d3c258 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
 #1: ffff8880b8d28a00 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
 #1: ffff8880b8d28a00 (psi_seq){-.-.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6696
 #2: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
 #2: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:838 [inline]
 #2: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: keep_key_fresh drivers/net/wireguard/send.c:129 [inline]
 #2: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: wg_packet_create_data_done drivers/net/wireguard/send.c:259 [inline]
 #2: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: wg_packet_tx_worker+0x25f/0x7d0 drivers/net/wireguard/send.c:276
 #3: ffffffff8df4bc88 (tk_core.seq.seqcount){----}-{0:0}, at: ktime_get_coarse_with_offset+0x88/0x190 kernel/time/timekeeping.c:910
 #4: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
 #4: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:838 [inline]
 #4: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: wg_packet_consume_data drivers/net/wireguard/receive.c:515 [inline]
 #4: ffffffff8df32140 (rcu_read_lock_bh){....}-{1:2}, at: wg_packet_receive+0x12b5/0x25d0 drivers/net/wireguard/receive.c:576
2 locks held by getty/8710:
 #0: ffff88814c7f50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000b6332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
7 locks held by syz.4.1626/11031:
1 lock held by syz.4.1626/11033:
 #0: ffff88802cd7f248 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040
5 locks held by syz.8.1628/11038:
 #0: ffff88805ea24e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
 #0: ffff88805ea24e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
 #1: ffff88805ea240b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x552/0x1170 net/bluetooth/hci_sync.c:5396
 #2: ffffffff8f341368 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2016 [inline]
 #2: ffffffff8f341368 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0x99/0x220 net/bluetooth/hci_conn.c:2592
 #3: ffff88802e0fe338 (&conn->lock#2){+.+.}-{3:3}, at: l2cap_conn_del+0x7b/0x630 net/bluetooth/l2cap_core.c:1796