INFO: task syz-executor.2:28721 blocked for more than 140 seconds.
      Not tainted 4.9.141+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28824 28721   2073 0x00000004
 ffff8801a3000000 ffff8801d4c6a680 ffff8801b1dce880 ffff8801a56e17c0
 ffff8801db721018 ffff880192937cf8 ffffffff828075c2 0000000000000000
 ffff8801a30008b0 ffffed0034600115 00ff8801a3000000 ffff8801db7218f0
Call Trace:
 [<ffffffff82808aef>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff828094a3>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff8280b51d>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff8280b51d>] mutex_lock_nested+0x38d/0x900 kernel/locking/mutex.c:621
 [<ffffffff82053de2>] evdev_flush+0x72/0x120 drivers/input/evdev.c:350
 [<ffffffff81502a77>] filp_close+0xa7/0x140 fs/open.c:1129
 [<ffffffff8156c826>] __close_fd+0x156/0x230 fs/file.c:651
 [<ffffffff81502b5c>] SYSC_close fs/open.c:1148 [inline]
 [<ffffffff81502b5c>] SyS_close+0x4c/0x90 fs/open.c:1146
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff82817893>] 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: [<ffffffff8131c0cc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c0cc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813fe63f>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/2022:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82815952>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81d37362>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor.2/28721:
 #0:  (&evdev->mutex){+.+.+.}, at: [<ffffffff82053de2>] evdev_flush+0x72/0x120 drivers/input/evdev.c:350

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

NMI backtrace for cpu 0
CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.141+ #1
 ffff8801d9907d08 ffffffff81b42e79 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810983b0 ffff8801d9907d40
 ffffffff81b4df89 0000000000000000 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81b42e79>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b42e79>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81b4df89>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81b4df1c>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff810984b4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8131c65d>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8131c65d>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8131c65d>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8131c65d>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff81142c3d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff82817a5c>] 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: 25677 Comm: syz-executor.3 Not tainted 4.9.141+ #1
task: ffff8801a43f0000 task.stack: ffff8801d0038000
RIP: 0010:[<ffffffff81208180>] 
c [<ffffffff81208180>] hlock_class kernel/locking/lockdep.c:142 [inline]
RIP: 0010:[<ffffffff81208180>] 
c [<ffffffff81208180>] lookup_chain_cache kernel/locking/lockdep.c:2122 [inline]
RIP: 0010:[<ffffffff81208180>] 
c [<ffffffff81208180>] validate_chain kernel/locking/lockdep.c:2236 [inline]
RIP: 0010:[<ffffffff81208180>] 
c [<ffffffff81208180>] __lock_acquire+0xdd0/0x4a10 kernel/locking/lockdep.c:3345
RSP: 0018:ffff8801d003fbe0  EFLAGS: 00000002
RAX: 00000000000001ea RBX: ffff8801a43f08b0 RCX: 00000000ffffff77
RDX: 0000000000000004 RSI: ffff8801a43f08b0 RDI: 0000000000000000
RBP: ffff8801d003fd88 R08: ffff8801a43f08d0 R09: 58f78840638c6916
R10: ffff8801a43f0000 R11: 0000000000000001 R12: 0000000000000089
R13: 0000000000000000 R14: 000000004e9b6192 R15: 0000000014f10784
FS:  00007f3d1494c700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c42831f000 CR3: 00000001c53a6000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801a43f0000
c ffffffff830cc2e0
c 0000000000000046
c ffff8801a43f0000
c
 ffff8801db721018
c ffff8801a43f08b0
c 000000000000001e
c 0000000000000000
c
 ffff8801a43f089c
c 0000000000000000
c ffff8801d003fde8
c ffffffff81207a04
c
Call Trace:
 [<ffffffff8120c8d0>] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
 [<ffffffff82816c26>] __raw_spin_lock include/linux/spinlock_api_smp.h:144 [inline]
 [<ffffffff82816c26>] _raw_spin_lock+0x36/0x50 kernel/locking/spinlock.c:151
 [<ffffffff8156bb66>] spin_lock include/linux/spinlock.h:302 [inline]
 [<ffffffff8156bb66>] __alloc_fd+0x36/0x4a0 fs/file.c:504
 [<ffffffff8156c06e>] get_unused_fd_flags+0x9e/0xd0 fs/file.c:562
 [<ffffffff8156d875>] SYSC_dup fs/file.c:944 [inline]
 [<ffffffff8156d875>] SyS_dup+0x35/0xb0 fs/file.c:938
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
c60 
c4c 
c8b 
c8c 
c24 
c98 
c00 
c00 
c00 
c48 
cb8 
ceb 
c83 
cb5 
c80 
c46 
c86 
cc8 
c61 
c44 
c8b 
c2d 
cd1 
c36 
cfe 
c02 
c49 
c0f 
caf 
cc1 
c48 
cc1 
ce8 
c31 
c66 
c45 
c85 
ce4 
c48 
c89 
c44 
c24 
c60 
c<48> 
c8d 
c04 
cc5 
c80 
cf9 
cc1 
c83 
c48 
c89 
c84 
c24 
c98 
c00 
c00 
c00 
c0f 
c84 
c4c 
c17 
c00 
c