lowmemorykiller: Killing 'syz-executor.0' (9426) (tgid 9413), adj 1000,
   to free 51420kB on behalf of 'udevd' (26092) because
   cache 424kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13340kB above reserved
INFO: task syz-executor.0:9443 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  D28960  9443   2102 0x00000004
 ffff8801d0b2df00 ffff8801d193c200 ffff8801c98c4d00 ffff8801d1f317c0
 ffff8801db721018 ffff88008c847a08 ffffffff828075c2 0000000000000000
 ffff8801d0b2e7b0 ffffed003a165cf5 00ff8801d0b2df00 ffff8801db7218f0
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
 [<ffffffff822e70e5>] copy_net_ns+0x155/0x330 net/core/net_namespace.c:406
 [<ffffffff811465e1>] create_new_namespaces+0x501/0x760 kernel/nsproxy.c:106
 [<ffffffff81146acd>] copy_namespaces+0x28d/0x320 kernel/nsproxy.c:164
 [<ffffffff810d528c>] copy_process.part.8+0x240c/0x6a10 kernel/fork.c:1695
 [<ffffffff810d9d12>] copy_process kernel/fork.c:1505 [inline]
 [<ffffffff810d9d12>] _do_fork+0x1b2/0xd30 kernel/fork.c:1972
 [<ffffffff810da967>] SYSC_clone kernel/fork.c:2084 [inline]
 [<ffffffff810da967>] SyS_clone+0x37/0x50 kernel/fork.c:2078
 [<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.0/9426:
 #0:  (net_mutex){+.+.+.}, at: [<ffffffff822e70e5>] copy_net_ns+0x155/0x330 net/core/net_namespace.c:406
1 lock held by syz-executor.0/9443:
 #0:  (net_mutex){+.+.+.}, at: [<ffffffff822e70e5>] copy_net_ns+0x155/0x330 net/core/net_namespace.c:406
3 locks held by kworker/0:11/9475:
 #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

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

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: 26092 Comm: udevd Not tainted 4.9.141+ #1
task: ffff8801d2dd2f80 task.stack: ffff880097e18000
RIP: 0010:[<ffffffff8120c913>] 
c [<ffffffff8120c913>] arch_local_irq_restore arch/x86/include/asm/paravirt.h:768 [inline]
RIP: 0010:[<ffffffff8120c913>] 
c [<ffffffff8120c913>] lock_acquire+0x173/0x3e0 kernel/locking/lockdep.c:3759
RSP: 0018:ffff880097e1f3f8  EFLAGS: 00000246
RAX: 0000000000000007 RBX: 0000000000000246 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8801d2dd38f8 RDI: 0000000000000246
RBP: ffff880097e1f460 R08: ffff8801d2dd3918 R09: ddd68c299640ddb6
R10: ffff8801d2dd2f80 R11: 0000000000000001 R12: ffff8801d2dd2f80
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fa719b247a0(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc82d5e6e40 CR3: 00000000b2232000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 0000000000000000
c ffffffff8141a061
c ffff880000000000
c ffff880000000000
c
 ffffffff81ba7d7b
c ffffffff81419f70
c 0000000000000000
c 00000001c56c97c0
c
 ffff8801c56c9f80
c ffff8801c56c97c0
c dffffc0000000000
c ffff8801c56c9f80
c
Call Trace:
 [<ffffffff82816c26>] __raw_spin_lock include/linux/spinlock_api_smp.h:144 [inline]
 [<ffffffff82816c26>] _raw_spin_lock+0x36/0x50 kernel/locking/spinlock.c:151
 [<ffffffff8141a061>] spin_lock include/linux/spinlock.h:302 [inline]
 [<ffffffff8141a061>] task_lock include/linux/sched.h:3257 [inline]
 [<ffffffff8141a061>] find_lock_task_mm+0xf1/0x270 mm/oom_kill.c:115
 [<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
 [<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: 
c03 
c0f 
cb6 
c14 
c02 
c48 
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cd0 
c7c 
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cd2 
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c01 
c00 
c00 
c41 
cc7 
c84 
c24 
cac 
c08 
c00 
c00 
c00 
c00 
c00 
c00 
c48 
c89 
cdf 
c57 
c9d 
c<0f> 
c1f 
c44 
c00 
c00 
c48 
c83 
cc4 
c40 
c5b 
c41 
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c41 
c5d 
c41 
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c41 
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c5d 
cc3 
c4c 
c