INFO: task syz-executor5:17997 blocked for more than 140 seconds.
      Not tainted 4.9.124+ #86
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D29112 17997   2284 0x00000004
 ffff8801ba7f97c0 ffff8801be593180 ffff8801be593180 ffff8801aa6fdf00
 ffff8801db720fd8 ffff8801aafbfcf8 ffffffff8277c6a2 0000000000000000
 ffff8801ba7fa070 ffffed00374ff40d 00ff8801ba7f97c0 ffff8801db7218b0
Call Trace:
 [<ffffffff8277dbcf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff8277e553>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff827801d6>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff827801d6>] mutex_lock_nested+0x326/0x870 kernel/locking/mutex.c:621
 [<ffffffff81fe7dc2>] evdev_flush+0x72/0x120 drivers/input/evdev.c:350
 [<ffffffff814e2e37>] filp_close+0xa7/0x140 fs/open.c:1129
 [<ffffffff8154bc26>] __close_fd+0x156/0x230 fs/file.c:651
 [<ffffffff814e2f1c>] SYSC_close fs/open.c:1148 [inline]
 [<ffffffff814e2f1c>] SyS_close+0x4c/0x90 fs/open.c:1146
 [<ffffffff8100554f>] do_syscall_64+0x19f/0x480 arch/x86/entry/common.c:282
 [<ffffffff8278b793>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309c30>] rcu_read_unlock include/linux/rcupdate.h:927 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309c30>] rcu_lock_break kernel/hung_task.c:143 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309c30>] check_hung_uninterruptible_tasks kernel/hung_task.c:177 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309c30>] watchdog+0x310/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813e687c>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/2215:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82789872>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81cdcd32>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor5/17997:
 #0:  (&evdev->mutex){+.+.+.}, at: [<ffffffff81fe7dc2>] evdev_flush+0x72/0x120 drivers/input/evdev.c:350

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

NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.124+ #86
 ffff8801d94a7d08 ffffffff81af03d9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff81096730 ffff8801d94a7d40
 ffffffff81afb139 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81af03d9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81af03d9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81afb139>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81afb0cc>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff81096834>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81309fcd>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81309fcd>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81309fcd>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81309fcd>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff8113d92d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff8278b95c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10009 Comm: syz-executor3 Not tainted 4.9.124+ #86
task: ffff8801aaac97c0 task.stack: ffff8801d8f90000
RIP: 0033:[<0000000000457099>] 
c [<0000000000457099>] 0x457099
RSP: 002b:00007f328debccf8  EFLAGS: 00000246
RAX: fffffffffffff001 RBX: 00000000009300a8 RCX: 0000000000457099
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000009300a8
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000009300ac
R13: 0000000000a3fb9f R14: 00007f328debd9c0 R15: 0000000000000000
FS:  00007f328debd700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002062b000 CR3: 00000001c302e000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400