313617 pages reserved
lowmemorykiller: Killing 'syz-executor.0' (6616) (tgid 6612), adj 1000,
   to free 34988kB on behalf of 'syz-executor.4' (2078) because
   cache 164kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13316kB above reserved
INFO: task kworker/0:0:4 blocked for more than 140 seconds.
      Not tainted 4.9.141+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:0     D29432     4      2 0x80000000
Workqueue: ipv6_addrconf addrconf_verify_work
 ffff8801da5fc740 ffff8801ce827380 ffff8801ce825800 ffff8801d038df00
 ffff8801db621018 ffff8801da667ae8 ffffffff828075c2 0000000000000002
 ffff8801da5fcff0 ffffed003b4bf9fd 00ff8801da5fc740 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
 [<ffffffff823412d7>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
 [<ffffffff826c31be>] addrconf_verify_work+0xe/0x20 net/ipv6/addrconf.c:4364
 [<ffffffff81131001>] process_one_work+0x831/0x15f0 kernel/workqueue.c:2092
 [<ffffffff81131e96>] worker_thread+0xd6/0x1140 kernel/workqueue.c:2226
 [<ffffffff81142c3d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff82817a5c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373

Showing all locks held in the system:
3 locks held by kworker/0:0/4:
 #0:  ("%s"("ipv6_addrconf")){.+.+..}, at: [<ffffffff81130f0c>] process_one_work+0x73c/0x15f0 kernel/workqueue.c:2085
 #1:  ((addr_chk_work).work){+.+...}, at: [<ffffffff81130f44>] process_one_work+0x774/0x15f0 kernel/workqueue.c:2089
 #2:  (rtnl_mutex){+.+.+.}, at: [<ffffffff823412d7>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
2 locks held by kworker/u4:0/6:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff81130f0c>] process_one_work+0x73c/0x15f0 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff81130f44>] process_one_work+0x774/0x15f0 kernel/workqueue.c:2089
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/2018:
 #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 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: 2078 Comm: syz-executor.4 Not tainted 4.9.141+ #1
task: ffff8801d038c740 task.stack: ffff8801a8218000
RIP: 0010:[<ffffffff8120cc58>] 
c [<ffffffff8120cc58>] trace_lock_release include/trace/events/lock.h:57 [inline]
RIP: 0010:[<ffffffff8120cc58>] 
c [<ffffffff8120cc58>] lock_release+0xd8/0xc20 kernel/locking/lockdep.c:3774
RSP: 0000:ffff8801a821f408  EFLAGS: 00000047
RAX: 0000000000000000 RBX: ffff8801d2f907d8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801d038cfec
RBP: ffff8801a821f4b0 R08: ffff8801d038d0b0 R09: df98b05b628c9890
R10: 0000000000000000 R11: 0000000000000001 R12: dffffc0000000000
R13: ffff8801d038c740 R14: ffff8801d2f90000 R15: 0000000000000600
FS:  000000000236f940(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000429cc0 CR3: 00000001a8201000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff880100000000
c ffff8801a821f450
c fffffbfff08489a8
c ffff8801d038cfe8
c
 ffff8801d038cff0
c 0000000000000246
c ffffffff00000000
c ffff880100000000
c
 0000000600000005
c ffff8801d038c740
c ffff8801d2f90000
c 0000000000000246
c
Call Trace:
 [<ffffffff82816eea>] __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
 [<ffffffff82816eea>] _raw_spin_unlock+0x1a/0x50 kernel/locking/spinlock.c:183
 [<ffffffff821f0166>] spin_unlock include/linux/spinlock.h:347 [inline]
 [<ffffffff821f0166>] task_unlock include/linux/sched.h:3262 [inline]
 [<ffffffff821f0166>] lowmem_scan+0x4d6/0xaf0 drivers/staging/android/lowmemorykiller.c:150
 [<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
 [<ffffffff81415701>] __alloc_pages include/linux/gfp.h:433 [inline]
 [<ffffffff81415701>] __alloc_pages_node include/linux/gfp.h:446 [inline]
 [<ffffffff81415701>] alloc_pages_node include/linux/gfp.h:460 [inline]
 [<ffffffff81415701>] __page_cache_alloc include/linux/pagemap.h:208 [inline]
 [<ffffffff81415701>] page_cache_read mm/filemap.c:2007 [inline]
 [<ffffffff81415701>] filemap_fault+0xaf1/0x1110 mm/filemap.c:2192
 [<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: 
c00 
c8b 
c05 
c34 
c08 
c1d 
c02 
c41 
cc7 
c85 
cac 
c08 
c00 
c00 
c01 
c00 
c00 
c00 
c85 
cc0 
c0f 
c8f 
cd6 
c07 
c00 
c00 
c65 
c8b 
c05 
ce2 
c94 
ce0 
c7e 
c89 
cc0 
c48 
c0f 
ca3 
c05 
ca0 
cad 
c1d 
c02 
c<0f> 
c82 
cf2 
c06 
c00 
c00 
c48 
cc7 
cc7 
c00 
c25 
c1f 
c83 
c48 
c89 
cfa 
c65 
c48 
c8b 
c04 
c25 
c