lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'getty' (20563) because
   cache 224kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13360kB above reserved
INFO: task syz-executor.0:20539 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.0  D30200 20539   2088 0x00000004
 ffff8801801dc740 ffff8801cfdcdd80 ffff8801a77f9b80 ffff8801d1f25f00[  716.206817] lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'getty' (20563) because
   cache 224kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12592kB above reserved
 ffff8801db721018 ffff880167107ad8 ffffffff828075c2 ffff880167107b58
 ffff8801801dc740 ffffffff810efada 00fffc0000000000 ffff8801db7218f0
Call Trace:
 [<ffffffff82808aef>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff822acffc>] __lock_sock+0x13c/0x250 net/core/sock.c:2035
 [<ffffffff822ad206>] lock_sock_nested+0xf6/0x120 net/core/sock.c:2505
 [<ffffffff827d2640>] lock_sock include/net/sock.h:1404 [inline]
 [<ffffffff827d2640>] packet_setsockopt+0xc10/0x2630 net/packet/af_packet.c:3856
lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'udevd' (5889) because
   cache 228kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12496kB above reserved
 [<ffffffff822a4d76>] SYSC_setsockopt net/socket.c:1785 [inline]
 [<ffffffff822a4d76>] SyS_setsockopt+0x166/0x260 net/socket.c:1764
 [<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/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
2 locks held by syz-executor.4/13781:
lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'syz-executor.0' (20536) because
   cache 228kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12496kB above reserved
 #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
2 locks held by syz-executor.2/17465:
 #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

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

lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'getty' (20566) because
   cache 228kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12496kB above reserved
lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'getty' (20563) because
   cache 228kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12496kB above reserved
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: 1892 Comm: rsyslogd Not tainted 4.9.141+ #1
task: ffff8801d3da17c0 task.stack: ffff8801d6700000
RIP: 0010:[<ffffffff81207614>] 
c [<ffffffff81207614>] __lock_acquire+0x264/0x4a10 kernel/locking/lockdep.c:3262
RSP: 0000:ffff8801d67070f0  EFLAGS: 00000806
RAX: ffff8801d3da20e8 RBX: 00000000000000a0 RCX: 0000000000000002
RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffff8801d3da2108
RBP: ffff8801d67072a0 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8801d3da17c0 R11: 1ffff1003a7b4421 R12: 000000000000001e
R13: 0000000000000004 R14: ffffffff830cc360 R15: 0000000000000000
FS:  00007f2b17b87700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f28fc6e84bc CR3: 00000001d4b4b000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d3da17c0
c dffffc0000000000
c ffffffff83c73d80
c ffffffff81206da7
c
 000000000000322a
c ffff8801d3da2128
c ffff8801d3da2060
c ffff8801d3da2130
c
 ffff8801d3da2068
c ffff8801d3da2070
c 1ffff1003ace0e2a
c ffffffff83c38ad0
c
Call Trace:
 [<ffffffff8120c8d0>] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
 [<ffffffff81419fb6>] rcu_lock_acquire include/linux/rcupdate.h:493 [inline]
 [<ffffffff81419fb6>] rcu_read_lock include/linux/rcupdate.h:875 [inline]
 [<ffffffff81419fb6>] find_lock_task_mm+0x46/0x270 mm/oom_kill.c:112
 [<ffffffff821effdf>] lowmem_scan+0x34f/0xaf0 drivers/staging/android/lowmemorykiller.c:134
 [<ffffffff81449cc6>] do_shrink_slab mm/vmscan.c:398 [inline]
 [<ffffffff81449cc6>] shrink_slab.part.8+0x3c6/0xa00 mm/vmscan.c:501
 [<ffffffff814557fd>] shrink_slab mm/vmscan.c:465 [inline]
 [<ffffffff814557fd>] shrink_node+0x1ed/0x740 mm/vmscan.c:2602
 [<ffffffff814560c7>] shrink_zones mm/vmscan.c:2749 [inline]
 [<ffffffff814560c7>] do_try_to_free_pages mm/vmscan.c:2791 [inline]
 [<ffffffff814560c7>] try_to_free_pages+0x377/0xb80 mm/vmscan.c:3002
 [<ffffffff81428a01>] __perform_reclaim mm/page_alloc.c:3324 [inline]
 [<ffffffff81428a01>] __alloc_pages_direct_reclaim mm/page_alloc.c:3345 [inline]
 [<ffffffff81428a01>] __alloc_pages_slowpath mm/page_alloc.c:3697 [inline]
 [<ffffffff81428a01>] __alloc_pages_nodemask+0x981/0x1bd0 mm/page_alloc.c:3862
 [<ffffffff8143564a>] __alloc_pages include/linux/gfp.h:433 [inline]
 [<ffffffff8143564a>] __alloc_pages_node include/linux/gfp.h:446 [inline]
 [<ffffffff8143564a>] alloc_pages_node include/linux/gfp.h:460 [inline]
 [<ffffffff8143564a>] __page_cache_alloc include/linux/pagemap.h:208 [inline]
 [<ffffffff8143564a>] __do_page_cache_readahead+0x21a/0x8b0 mm/readahead.c:183
 [<ffffffff81415534>] ra_submit mm/internal.h:59 [inline]
 [<ffffffff81415534>] do_sync_mmap_readahead mm/filemap.c:2066 [inline]
 [<ffffffff81415534>] filemap_fault+0x924/0x1110 mm/filemap.c:2143
 [<ffffffff816e7721>] ext4_filemap_fault+0x71/0xa0 fs/ext4/inode.c:5853
 [<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
 [<ffffffff810b2b33>] __do_page_fault+0x403/0xa60 arch/x86/mm/fault.c:1406
 [<ffffffff810b31e7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff828188b5>] page_fault+0x25/0x30 arch/x86/entry/entry_64.S:951
Code: 
c01 
c44 
c89 
ce8 
c48 
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c1c 
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c48 
cc1 
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c03 
c45 
c85 
ced 
c74 
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c48 
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c44 
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cd8 
c48 
cbe 
c00 
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c00 
cfc 
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cdf 
c48 
c8d 
c78 
c20 
c49 
c89 
cfb 
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cc1 
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c03 
c<41> 
c0f 
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c34 
c33 
c40 
c84 
cf6 
c74 
c0a 
c40 
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cfe 
c03 
c0f 
c8e 
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c13 
c00 
c00 
c0f 
c