Free memory is 23780kB above reserved
lowmemorykiller: Killing 'syz-executor.5' (28658) (tgid 28658), adj 1000,
   to free 51604kB on behalf of 'kswapd0' (33) because
   cache 19952kB is below limit 65536kB for oom_score_adj 12
   Free memory is 50544kB above reserved
INFO: task init:32658 blocked for more than 140 seconds.
      Not tainted 4.9.141+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
init            D29336 32658      1 0x00000000
 ffff880081714740 ffff8800ab9df900 ffff8801a7244d00 ffff88015bb5c740
 ffff8801db621018 ffff880174757738 ffffffff828075c2 0000000000000000
 ffff880081714ff0 ffffed00102e29fd 00ff880081714740 ffff8801db6218f0
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
 [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
 [<ffffffff81517bdd>] chrdev_open+0x22d/0x5c0 fs/char_dev.c:392
 [<ffffffff81501e3f>] do_dentry_open+0x3ef/0xc90 fs/open.c:766
 [<ffffffff8150576c>] vfs_open+0x11c/0x210 fs/open.c:879
 [<ffffffff8153c542>] do_last fs/namei.c:3410 [inline]
 [<ffffffff8153c542>] path_openat+0x542/0x2790 fs/namei.c:3534
 [<ffffffff81541617>] do_filp_open+0x197/0x270 fs/namei.c:3568
 [<ffffffff8150617d>] do_sys_open+0x30d/0x5c0 fs/open.c:1072
 [<ffffffff8150645d>] SYSC_open fs/open.c:1090 [inline]
 [<ffffffff8150645d>] SyS_open+0x2d/0x40 fs/open.c:1085
 [<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
1 lock held by rsyslogd/1896:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8156cc7c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/2023:
 #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.1/2069:
 #0:  (tasklist_lock){.+.+..}, at: [<ffffffff810ec902>] do_wait+0x392/0x950 kernel/exit.c:1558
2 locks held by kworker/1:11/19954:
 #0:  ("events"){.+.+.+}, at: [<ffffffff81130f0c>] process_one_work+0x73c/0x15f0 kernel/workqueue.c:2085
 #1:  ((&ns->proc_work)){+.+...}, at: [<ffffffff81130f44>] process_one_work+0x774/0x15f0 kernel/workqueue.c:2089
1 lock held by init/32658:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/32659:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/32661:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/32662:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/32663:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/32666:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by syz-executor.1/15779:
 #0:  (input_mutex){+.+.+.}, at: [<ffffffff82046052>] __input_unregister_device+0x152/0x490 drivers/input/input.c:2020
1 lock held by syz-executor.3/15792:
 #0:  (input_mutex){+.+.+.}, at: [<ffffffff82046052>] __input_unregister_device+0x152/0x490 drivers/input/input.c:2020
2 locks held by syz-executor.0/15824:
 #0:  (&type->s_umount_key#4/1){+.+.+.}, at: [<ffffffff815133c2>] alloc_super fs/super.c:241 [inline]
 #0:  (&type->s_umount_key#4/1){+.+.+.}, at: [<ffffffff815133c2>] sget_userns+0x552/0xc40 fs/super.c:503
 #1:  (shrinker_rwsem){++++..}, at: [<ffffffff814483ae>] register_shrinker+0x8e/0x180 mm/vmscan.c:286

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

NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.141+ #1
 ffff8801d9907d08 ffffffff81b42e79 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810983b0 ffff8801d9907d40
 ffffffff81b4df89 0000000000000001 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15750 Comm: syz-executor.5 Not tainted 4.9.141+ #1
task: ffff8801a780c740 task.stack: ffff8800651c8000
RIP: 0010:[<ffffffff81ba8129>] 
c [<ffffffff81ba8129>] __list_del_entry_valid+0x89/0x1a0 lib/list_debug.c:51
RSP: 0018:ffff8800651cf588  EFLAGS: 00000046
RAX: ffffea00048ba0a0 RBX: ffffea00046dbf20 RCX: ffffea00048ba0a0
RDX: 1ffffd40008db7e4 RSI: ffffffff8143c19d RDI: ffffea00048ba0a8
RBP: ffff8800651cf5a0 R08: ffffea0001f800a0 R09: 2db45dc6a21baa3c
R10: ffff8801a780c740 R11: 0000000000000001 R12: ffffea00048ba0a0
R13: ffffea00048ba0a8 R14: ffff8801d6b35c28 R15: dffffc0000000000
FS:  00007fd242935700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f506a771518 CR3: 00000001ad587000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff833d3600
c ffff8801d6b35c20
c ffffea00048ba080
c ffff8800651cf680
c
 ffffffff8143c1a9
c ffff8800651cf5c0
c ffffffff81243c87
c ffff880000000001
c
 1ffff1000ca39ebf
c ffffea0000000002
c ffff8800651cf618
c 0000000000000296
c
Call Trace:
 [<ffffffff8143c1a9>] __list_del_entry include/linux/list.h:116 [inline]
 [<ffffffff8143c1a9>] list_del include/linux/list.h:124 [inline]
 [<ffffffff8143c1a9>] del_page_from_lru_list include/linux/mm_inline.h:56 [inline]
 [<ffffffff8143c1a9>] release_pages+0x579/0xaa0 mm/swap.c:782
 [<ffffffff814d1b57>] free_pages_and_swap_cache+0x117/0x160 mm/swap_state.c:273
 [<ffffffff81492374>] tlb_flush_mmu_free+0xb4/0x150 mm/memory.c:259
 [<ffffffff81499d1a>] zap_pte_range mm/memory.c:1207 [inline]
 [<ffffffff81499d1a>] zap_pmd_range mm/memory.c:1249 [inline]
 [<ffffffff81499d1a>] zap_pud_range mm/memory.c:1270 [inline]
 [<ffffffff81499d1a>] unmap_page_range+0x106a/0x1680 mm/memory.c:1291
 [<ffffffff8149a44c>] unmap_single_vma+0x11c/0x170 mm/memory.c:1336
 [<ffffffff8149ab51>] unmap_vmas+0x81/0xd0 mm/memory.c:1366
 [<ffffffff814b0c2c>] exit_mmap+0x1cc/0x3a0 mm/mmap.c:3021
 [<ffffffff810d265d>] __mmput kernel/fork.c:884 [inline]
 [<ffffffff810d265d>] mmput+0xcd/0x360 kernel/fork.c:906
 [<ffffffff810e6b89>] exit_mm kernel/exit.c:514 [inline]
 [<ffffffff810e6b89>] do_exit+0x6c9/0x2a50 kernel/exit.c:820
 [<ffffffff810ed3a1>] do_group_exit+0x111/0x300 kernel/exit.c:937
 [<ffffffff8110eb61>] get_signal+0x4e1/0x1460 kernel/signal.c:2321
 [<ffffffff81052aa5>] do_signal+0x95/0x1b00 arch/x86/kernel/signal.c:807
 [<ffffffff81003e2e>] exit_to_usermode_loop+0x10e/0x150 arch/x86/entry/common.c:158
 [<ffffffff81005932>] prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 [<ffffffff81005932>] syscall_return_slowpath arch/x86/entry/common.c:263 [inline]
 [<ffffffff81005932>] do_syscall_64+0x3e2/0x550 arch/x86/entry/common.c:290
 [<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
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c<48> 
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c