protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
INFO: task getty:7211 blocked for more than 140 seconds.
      Not tainted 4.14.163-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
getty           D25952  7211      1 0x80000002
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723
 down_write_failed drivers/tty/tty_ldsem.c:298 [inline]
 __ldsem_down_write_nested+0x304/0x7b0 drivers/tty/tty_ldsem.c:360
 ldsem_down_write+0x33/0x39 drivers/tty/tty_ldsem.c:402
 __tty_ldisc_lock drivers/tty/tty_ldisc.c:332 [inline]
 tty_ldisc_lock+0x50/0x80 drivers/tty/tty_ldisc.c:356
 tty_ldisc_hangup+0x1a6/0x5e0 drivers/tty/tty_ldisc.c:758
 __tty_hangup.part.0+0x2d3/0x6d0 drivers/tty/tty_io.c:622
 __tty_hangup drivers/tty/tty_io.c:572 [inline]
 tty_vhangup_session+0x25/0x30 drivers/tty/tty_io.c:732
 disassociate_ctty.part.0+0x9b/0x6c0 drivers/tty/tty_jobctrl.c:266
 disassociate_ctty+0x78/0x90 drivers/tty/tty_jobctrl.c:260
 do_exit+0x17c6/0x2cd0 kernel/exit.c:856
 do_group_exit+0x111/0x330 kernel/exit.c:955
 SYSC_exit_group kernel/exit.c:966 [inline]
 SyS_exit_group+0x1d/0x20 kernel/exit.c:964
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f7eb60fa1e8
RSP: 002b:00007ffe485f8a18 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f7eb60fa1e8
RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
RBP: 00007f7eb63cf840 R08: 00000000000000e7 R09: ffffffffffffffa8
R10: 00007f7eb63d5740 R11: 0000000000000246 R12: 00007f7eb63cf840
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
INFO: task kworker/u4:2:11050 blocked for more than 140 seconds.
      Not tainted 4.14.163-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:2    D25968 11050      2 0x80000000
Workqueue: events_unbound flush_to_ldisc
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 flush_to_ldisc+0x39/0x400 drivers/tty/tty_buffer.c:499
 process_one_work+0x863/0x1600 kernel/workqueue.c:2114
 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Showing all locks held in the system:
1 lock held by khungtaskd/1059:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff81489c18>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544
2 locks held by getty/7211:
 #0:  (&tty->legacy_mutex){+.+.}, at: [<ffffffff834dc9b8>] tty_lock+0x68/0x80 drivers/tty/tty_mutex.c:19
 #1:  (&tty->ldisc_sem){++++}, at: [<ffffffff866a3a73>] ldsem_down_write+0x33/0x39 drivers/tty/tty_ldsem.c:402
2 locks held by getty/7212:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff866a3a33>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834ca1b6>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7213:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff866a3a33>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834ca1b6>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7214:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff866a3a33>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834ca1b6>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7215:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff866a3a33>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834ca1b6>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7216:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff866a3a33>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834ca1b6>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7217:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff866a3a33>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834ca1b6>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
3 locks held by kworker/u4:2/11050:
 #0:  ("events_unbound"){+.+.}, at: [<ffffffff813d315e>] work_static include/linux/workqueue.h:199 [inline]
 #0:  ("events_unbound"){+.+.}, at: [<ffffffff813d315e>] set_work_data kernel/workqueue.c:619 [inline]
 #0:  ("events_unbound"){+.+.}, at: [<ffffffff813d315e>] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0:  ("events_unbound"){+.+.}, at: [<ffffffff813d315e>] process_one_work+0x76e/0x1600 kernel/workqueue.c:2085
 #1:  ((&buf->work)){+.+.}, at: [<ffffffff813d319b>] process_one_work+0x7ab/0x1600 kernel/workqueue.c:2089
 #2:  (&buf->lock){+.+.}, at: [<ffffffff834d92b9>] flush_to_ldisc+0x39/0x400 drivers/tty/tty_buffer.c:499

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1059 Comm: khungtaskd Not tainted 4.14.163-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x142/0x197 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x141/0x189 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5e7/0xb90 kernel/hung_task.c:274
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 20427 Comm: syz-executor.5 Not tainted 4.14.163-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888090bbc200 task.stack: ffff8880791b8000
RIP: 0010:match_held_lock+0xa4/0x5f0 kernel/locking/lockdep.c:3558
RSP: 0018:ffff8880791bf7b0 EFLAGS: 00000046
RAX: 0000000000000003 RBX: ffff888090bbca80 RCX: ffff888090bbca80
RDX: 0000000000000000 RSI: ffff8880aed2b558 RDI: ffff888090bbcaa2
RBP: ffff8880791bf828 R08: 00000000000034ec R09: ffffffff89585120
R10: ffff888090bbcad0 R11: ffff888090bbc200 R12: ffff8880aed2b558
R13: 1ffff1100f237ef8 R14: ffff8880aed2b558 R15: ffff8880791bf800
FS:  00007fd877fd1700(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c433c54f10 CR3: 00000000a0f58000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __lock_is_held+0xb6/0x140 kernel/locking/lockdep.c:3814
 lock_is_held_type+0x110/0x210 kernel/locking/lockdep.c:4032
 lock_is_held include/linux/lockdep.h:437 [inline]
 update_rq_clock+0x24a/0x2e0 kernel/sched/core.c:216
 __schedule+0x232/0x1cd0 kernel/sched/core.c:3326
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 paste_selection+0x293/0x3f2 drivers/tty/vt/selection.c:355
 tioclinux+0x10e/0x400 drivers/tty/vt/vt.c:2696
 vt_ioctl+0x180c/0x2170 drivers/tty/vt/vt_ioctl.c:364
 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45af49
RSP: 002b:00007fd877fd0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045af49
RDX: 0000000020000000 RSI: 000000000000541c RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd877fd16d4
R13: 00000000004c6498 R14: 00000000004ddb18 R15: 00000000ffffffff
Code: 22 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 6a 03 00 00 <66> f7 43 22 f0 ff 0f 84 0f 02 00 00 49 8d 7e 08 48 b8 00 00 00