INFO: task syz-executor5:7152 blocked for more than 140 seconds.
      Not tainted 4.9.128+ #93
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D28832  7152   2094 0x00000004
 ffff8801cc9c17c0 ffff8801d1ed7380 ffff8801d3260000 ffff8801d1f95f00
 ffff8801db721018 ffff8801a93a7cf8 ffffffff8277ee02 0000000000000000
 ffff8801cc9c2070 ffffed003993840d 00ff8801cc9c17c0 ffff8801db7218f0
Call Trace:
 [<ffffffff8278032f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff82780cb3>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff82782936>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff82782936>] mutex_lock_nested+0x326/0x870 kernel/locking/mutex.c:621
 [<ffffffff81fea2b2>] evdev_flush+0x72/0x120 drivers/input/evdev.c:350
 [<ffffffff814e3487>] filp_close+0xa7/0x140 fs/open.c:1129
 [<ffffffff8154c2a6>] __close_fd+0x156/0x230 fs/file.c:651
 [<ffffffff814e356c>] SYSC_close fs/open.c:1148 [inline]
 [<ffffffff814e356c>] SyS_close+0x4c/0x90 fs/open.c:1146
 [<ffffffff8100554f>] do_syscall_64+0x19f/0x480 arch/x86/entry/common.c:282
 [<ffffffff8278df13>] 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: [<ffffffff8130a0ac>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8130a0ac>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813e71ec>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/2029:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff8278bfd2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81cdee72>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor5/7152:
 #0:  (&evdev->mutex){+.+.+.}, at: [<ffffffff81fea2b2>] evdev_flush+0x72/0x120 drivers/input/evdev.c:350
1 lock held by syz-executor4/7217:
 #0:  (&evdev->mutex){+.+.+.}, at: [<ffffffff81fed5eb>] evdev_open_device drivers/input/evdev.c:423 [inline]
 #0:  (&evdev->mutex){+.+.+.}, at: [<ffffffff81fed5eb>] evdev_open+0x1db/0x430 drivers/input/evdev.c:516

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

NMI backtrace for cpu 0
CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.128+ #93
 ffff8801d9907d08 ffffffff81af2469 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810967d0 ffff8801d9907d40
 ffffffff81afd1c9 0000000000000000 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81af2469>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81af2469>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81afd1c9>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81afd15c>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff810968d4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8130a63d>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8130a63d>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8130a63d>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8130a63d>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff8113e00d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff8278e0dc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4648 Comm: syz-executor4 Not tainted 4.9.128+ #93
task: ffff8801d6dadf00 task.stack: ffff8801d7200000
RIP: 0010:[<ffffffff81309a4d>] 
c [<ffffffff81309a4d>] get_current arch/x86/include/asm/current.h:14 [inline]
RIP: 0010:[<ffffffff81309a4d>] 
c [<ffffffff81309a4d>] __sanitizer_cov_trace_pc+0xd/0x50 kernel/kcov.c:99
RSP: 0018:ffff8801d7207ef0  EFLAGS: 00000046
RAX: ffff8801d6dadf00 RBX: ffff8801d7207f58 RCX: 0000000000000000
RDX: 1ffff1003adb5be0 RSI: ffffffff810055f0 RDI: ffff8801d6dae7a8
RBP: ffff8801d7207ef0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d6dadf00
R13: 0000000000000100 R14: ffff8801d6dadf00 R15: 0000000000000000
FS:  00007f452efad700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020683000 CR3: 00000001d807a000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d7207f48
c ffffffff81005626
c 0000000000000000
c 0000000000000000
c
 0000000000000000
c 0000000000000000
c 0000000000000000
c 0000000000000000
c
 0000000000000000
c 0000000000000000
c 0000000000000000
c 0000000000000000
c
Call Trace:
 [<ffffffff81005626>] prepare_exit_to_usermode arch/x86/entry/common.c:205 [inline]
 [<ffffffff81005626>] syscall_return_slowpath arch/x86/entry/common.c:260 [inline]
 [<ffffffff81005626>] do_syscall_64+0x276/0x480 arch/x86/entry/common.c:287
 [<ffffffff8278df13>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
c5f 
cff 
cff 
cff 
c48 
c89 
cdf 
ce8 
cd2 
ca1 
c1c 
c00 
ce9 
cf9 
cfe 
cff 
cff 
c66 
c2e 
c0f 
c1f 
c84 
c00 
c00 
c00 
c00 
c00 
c0f 
c1f 
c00 
c55 
c48 
c89 
ce5 
c65 
c48 
c8b 
c04 
c25 
c00 
c7e 
c01 
c00 
c<65> 
c8b 
c15 
c3c 
ce3 
cd0 
c7e 
c81 
ce2 
c00 
c01 
c1f 
c00 
c48 
c8b 
c75 
c08 
c75 
c2b 
c8b 
c90 
c