Free memory is -13472kB above reserved
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'init' (13782) because
   cache 1488kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13472kB above reserved
INFO: task syz-executor.0:13766 blocked for more than 140 seconds.
      Not tainted 4.9.141+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D29992 13766   4997 0x20020004
 ffff8801043e0000 ffff8800b8233700 ffff8800b8230580 ffff880030cb4740
 ffff8801db621018 ffff8800097bfa88 ffffffff828075c2 ffff8800097bfb08
 ffff8801043e0000 ffffffff810efada 00fffc0000000000 ffff8801db6218f0
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
 [<ffffffff827d1f3f>] lock_sock include/net/sock.h:1404 [inline]
 [<ffffffff827d1f3f>] packet_setsockopt+0x50f/0x2630 net/packet/af_packet.c:3668
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'syz-fuzzer' (2066) because
   cache 1352kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13428kB above reserved
 [<ffffffff827d4141>] compat_packet_setsockopt+0xe1/0x140 net/packet/af_packet.c:4016
 [<ffffffff8238f7d9>] C_SYSC_setsockopt net/compat.c:399 [inline]
 [<ffffffff8238f7d9>] compat_SyS_setsockopt+0x169/0x550 net/compat.c:382
 [<ffffffff81006311>] do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline]
 [<ffffffff81006311>] do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'syz-executor.0' (13762) because
   cache 1428kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13320kB above reserved
 [<ffffffff82818de0>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c2c0>] rcu_read_unlock include/linux/rcupdate.h:927 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c2c0>] rcu_lock_break kernel/hung_task.c:143 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c2c0>] check_hung_uninterruptible_tasks kernel/hung_task.c:177 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c2c0>] watchdog+0x310/0xa20 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/2021:
 #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

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

NMI backtrace for cpu 0
CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.141+ #23
 ffff8801d9907d08 ffffffff81b42e79 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810983b0 ffff8801d9907d40
 ffffffff81b4df89 0000000000000000 0000000000000000 0000000000000003
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: 2050 Comm: syz-fuzzer Not tainted 4.9.141+ #23
task: ffff8801d01897c0 task.stack: ffff8801cffa0000
RIP: 0010:[<ffffffff8131ba86>] 
c [<ffffffff8131ba86>] __sanitizer_cov_trace_pc+0x26/0x50 kernel/kcov.c:100
RSP: 0000:ffff8801cffa72a8  EFLAGS: 00000246
RAX: ffff8801d01897c0 RBX: ffff88009e7c17c0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81ba7d5c RDI: ffffffff82b447e0
RBP: ffff8801cffa72a8 R08: ffff8801d018a130 R09: 74de1bb591a33f7d
R10: ffff8801d01897c0 R11: 0000000000000001 R12: ffffffff82b447e0
R13: ffffffff82b447a0 R14: ffff88009e31af80 R15: 0000000000000600
FS:  000000c420088ae8(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000445ae0 CR3: 00000001cfca6000 CR4: 00000000001606b0
Stack:
 ffff8801cffa72e8
c ffffffff81ba7d5c
c ffffffff81419f70
c ffff88009e7c17c0
c
 ffff88009e7c17c0
c ffff88009e7c1bd8
c ffff88009e31af80
c 0000000000000600
c
 ffff8801cffa72f8
c ffffffff81ba7f5c
c ffff8801cffa7318
c ffffffff81247305
c
Call Trace:
 [<ffffffff81ba7d5c>] check_preemption_disabled+0x1c/0x200 lib/smp_processor_id.c:13
 [<ffffffff81ba7f5c>] debug_smp_processor_id+0x1c/0x20 lib/smp_processor_id.c:56
 [<ffffffff81247305>] __rcu_is_watching kernel/rcu/tree.c:1053 [inline]
 [<ffffffff81247305>] rcu_is_watching+0x15/0xa0 kernel/rcu/tree.c:1067
 [<ffffffff8141a11b>] rcu_read_lock include/linux/rcupdate.h:876 [inline]
 [<ffffffff8141a11b>] find_lock_task_mm+0x1ab/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: 
cff 
cff 
c0f 
c1f 
c00 
c55 
c48 
c89 
ce5 
c48 
c8b 
c75 
c08 
c65 
c48 
c8b 
c04 
c25 
c00 
c7e 
c01 
c00 
c65 
c8b 
c15 
c18 
cc3 
ccf 
c7e 
c81 
ce2 
c00 
c01 
c1f 
c00 
c75 
c2b 
c8b 
c90 
c38 
c12 
c00 
c00 
c<83> 
cfa 
c02 
c75 
c20 
c48 
c8b 
c88 
c40 
c12 
c00 
c00 
c8b 
c80 
c3c 
c12 
c00 
c00 
c48 
c8b 
c11 
c
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'rs:main Q:Reg' (1891) because
   cache 1428kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13404kB above reserved
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'init' (13776) because
   cache 1428kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13404kB above reserved
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'rs:main Q:Reg' (1891) because
   cache 1388kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13324kB above reserved
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'init' (13776) because
   cache 1388kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13324kB above reserved
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'init' (13778) because
   cache 1280kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13216kB above reserved
lowmemorykiller: Killing 'syz-executor.0' (13762) (tgid 13758), adj 1000,
   to free 34984kB on behalf of 'rsyslogd' (1893) because
   cache 1280kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13216kB above reserved