INFO: task syz-executor:10643 blocked for more than 151 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22152 pid:10643 tgid:10643 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307 rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline] mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547 del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:234 kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5d5/0xb40 fs/read_write.c:686 ksys_write+0x14b/0x260 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2cc99ee17f RSP: 002b:00007ffc75e841c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f2cc99ee17f RDX: 0000000000000001 RSI: 00007ffc75e84210 RDI: 0000000000000005 RBP: 00007f2cc9a732cb R08: 0000000000000000 R09: 00007ffc75e84017 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffc75e84210 R14: 00007f2cca774620 R15: 0000000000000003 Showing all locks held in the system: 3 locks held by kworker/0:0/9: #0: ffff88813ff56138 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88813ff56138 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc900000e7ba0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc900000e7ba0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8e8632f8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xa1/0xf40 net/wireless/reg.c:2453 5 locks held by pr/legacy/17: 1 lock held by khungtaskd/38: #0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:3/58: 5 locks held by kworker/u9:0/61: #0: ffff88805c493138 ((wq_completion)hci4){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88805c493138 ((wq_completion)hci4){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000127fba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000127fba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888055e24e88 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 #3: ffff888055e240a8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x242/0xe30 net/bluetooth/hci_sync.c:5684 #4: ffffffff8e9cb778 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2104 [inline] #4: ffffffff8e9cb778 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x310 net/bluetooth/hci_conn.c:1319 5 locks held by kworker/u8:5/82: 2 locks held by kworker/0:2/990: 3 locks held by kworker/u8:6/1177: #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000522fba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000522fba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8e8632f8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by kworker/1:2/1217: 2 locks held by dhcpcd/5465: #0: ffffffff8e847758 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5f1/0x790 net/socket.c:1337 #1: ffffffff8e8632f8 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:579 2 locks held by getty/5561: #0: ffff88823bf400a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e932e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5802: 6 locks held by kworker/u9:2/5811: #0: ffff88805d128938 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88805d128938 ((wq_completion)hci0){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90004bdfba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90004bdfba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff88805eb00e88 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 #3: ffff88805eb000a8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x242/0xe30 net/bluetooth/hci_sync.c:5684 #4: ffffffff8e9cb778 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2104 [inline] #4: ffffffff8e9cb778 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x310 net/bluetooth/hci_conn.c:1319