lowmemorykiller: Killing 'syz-executor823' (15028) (tgid 15028), adj 1000,
   to free 11960kB on behalf of 'syz-executor823' (2096) because
   cache 952kB is below limit 65536kB for oom_score_adj 12
   Free memory is 60924kB above reserved
INFO: task init:6168 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            D28888  6168      1 0x00000000
 ffff8801caf98000 ffff8801ca600000 ffff8801ca600580 ffff88009c7ec740
 ffff8801db621018 ffff8801ca65f580 ffffffff828075c2 ffff8801caf988b0
 000000000000015c 0000000000000000 0000000000000000 ffff8801db6218f0
Call Trace:
 [<ffffffff82808aef>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff828142d5>] schedule_timeout+0x735/0xe20 kernel/time/timer.c:1771
 [<ffffffff828108c1>] __down_common kernel/locking/semaphore.c:221 [inline]
 [<ffffffff828108c1>] __down+0x191/0x2b0 kernel/locking/semaphore.c:238
 [<ffffffff811fcbfe>] down+0x5e/0x80 kernel/locking/semaphore.c:61
 [<ffffffff812223ac>] console_lock+0x2c/0x80 kernel/printk/printk.c:2217
 [<ffffffff8122793c>] console_device+0x1c/0xc0 kernel/printk/printk.c:2554
 [<ffffffff81d2be15>] tty_lookup_driver drivers/tty/tty_io.c:2008 [inline]
 [<ffffffff81d2be15>] tty_open_by_driver drivers/tty/tty_io.c:2053 [inline]
 [<ffffffff81d2be15>] tty_open+0x6f5/0xdf0 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/1892:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8156cc7c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/2019:
 #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 init/6168:
 #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/6169:
 #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/6170:
 #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/6171:
 #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/6172:
 #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/6173:
 #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

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

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: 15096 Comm: syz-executor823 Not tainted 4.9.141+ #1
task: ffff8801d9b9df00 task.stack: ffff88007a5e0000
RIP: 0010:[<ffffffff8120fe50>] 
c [<ffffffff8120fe50>] in_lock_functions+0x0/0x20 kernel/locking/spinlock.c:405
RSP: 0018:ffff88007a5e76b0  EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff81b4f15d RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81b4f153 RDI: ffffffff81b4f15d
RBP: ffff88007a5e76c8 R08: ffff8801d9b9e7b0 R09: ffffed0000cefa00
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000015 R14: 00000000024000c0 R15: ffffea000019df40
FS:  00007f0efc2f7700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0efc2f6e78 CR3: 0000000079649000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff811675fc
c 0000000000000000
c 00000000024000c0
c ffff88007a5e7708
c
 ffffffff81b4f15d
c 000000000000012b
c 0000000000000000
c 00000000024000c0
c
 0000000000000000
c 0000000000000015
c ffffea000019df40
c ffff88007a5e7738
c
Call Trace:
 [<ffffffff81b4f15d>] __radix_tree_preload+0x2d/0x260 lib/radix-tree.c:360
 [<ffffffff81b515bf>] radix_tree_maybe_preload_order+0x9f/0xf0 lib/radix-tree.c:456
 [<ffffffff814616f8>] shmem_getpage_gfp+0xd78/0x18f0 mm/shmem.c:1760
 [<ffffffff81462602>] shmem_fault+0x222/0x6d0 mm/shmem.c:1959
 [<ffffffff81492ef3>] __do_fault+0x223/0x500 mm/memory.c:2833
 [<ffffffff814a3696>] do_read_fault mm/memory.c:3180 [inline]
 [<ffffffff814a3696>] do_fault mm/memory.c:3315 [inline]
 [<ffffffff814a3696>] handle_pte_fault mm/memory.c:3516 [inline]
 [<ffffffff814a3696>] __handle_mm_fault mm/memory.c:3603 [inline]
 [<ffffffff814a3696>] handle_mm_fault+0x1326/0x2350 mm/memory.c:3640
 [<ffffffff81490406>] faultin_page mm/gup.c:386 [inline]
 [<ffffffff81490406>] __get_user_pages+0x446/0xf80 mm/gup.c:588
 [<ffffffff81491d6a>] populate_vma_page_range+0x19a/0x230 mm/gup.c:1106
 [<ffffffff81491fd7>] __mm_populate+0x1d7/0x320 mm/gup.c:1154
 [<ffffffff81469f25>] mm_populate include/linux/mm.h:2041 [inline]
 [<ffffffff81469f25>] vm_mmap_pgoff+0x195/0x1b0 mm/util.c:333
 [<ffffffff814af5c2>] SYSC_mmap_pgoff mm/mmap.c:1555 [inline]
 [<ffffffff814af5c2>] SyS_mmap_pgoff+0x152/0x1b0 mm/mmap.c:1513
 [<ffffffff8105d3e6>] SYSC_mmap arch/x86/kernel/sys_x86_64.c:96 [inline]
 [<ffffffff8105d3e6>] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:87
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
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c<31> 
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c