INFO: task kworker/u4:3:62 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc5+ #99
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:3    D24632    62      2 0x80000000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
 cangw_pernet_exit+0x13/0x30 net/can/gw.c:1029
 ops_exit_list.isra.0+0xb0/0x160 net/core/net_namespace.c:153
 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:552
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
INFO: task kworker/1:12:18825 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc5+ #99
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:12    D26944 18825      2 0x80000000
Workqueue: events switchdev_deferred_process_work
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
 switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:78
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
INFO: task kworker/1:16:21923 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc5+ #99
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:16    D26880 21923      2 0x80000000
Workqueue: events linkwatch_event
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
 linkwatch_event+0xf/0x70 net/core/link_watch.c:236
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
INFO: task syz-executor.2:9819 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc5+ #99
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28384  9819  27883 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
 tun_detach drivers/net/tun.c:740 [inline]
 tun_chr_close+0x3f/0x180 drivers/net/tun.c:3450
 __fput+0x2e5/0x8d0 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x14a/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x412b61
Code: 01 00 00 64 48 8b 04 25 f8 ff ff ff 48 8b 40 30 48 8b 80 98 00 00 00 48 85 c0 74 15 48 8b 08 48 39 d1 77 0d 48 8b 40 08 48 39 <c2> 0f 82 fb 00 00 00 48 8b 05 31 d5 33 01 48 85 c0 0f 84 e2 00 00
RSP: 002b:00007ffc98918240 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412b61
RDX: 0000001b32620000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000001 R08: 000000000536b032 R09: 000000000536b036
R10: 00007ffc98918320 R11: 0000000000000293 R12: 000000000073c900
R13: 000000000073c900 R14: 000000000023c2c3 R15: 000000000073bf0c
INFO: task syz-executor.1:9822 blocked for more than 144 seconds.
      Not tainted 5.1.0-rc5+ #99
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D28384  9822  28073 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 exp_funnel_lock kernel/rcu/tree_exp.h:308 [inline]
 synchronize_rcu_expedited+0x54e/0x5b0 kernel/rcu/tree_exp.h:758
 synchronize_net+0x3b/0x60 net/core/dev.c:9277
 tun_detach_all+0x3df/0x850 drivers/net/tun.c:771
 tun_net_uninit+0x16/0x20 drivers/net/tun.c:1013
 rollback_registered_many+0xac2/0xfd0 net/core/dev.c:8228
 rollback_registered+0x109/0x1d0 net/core/dev.c:8256
 unregister_netdevice_queue net/core/dev.c:9303 [inline]
 unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9296
 unregister_netdevice include/linux/netdevice.h:2656 [inline]
 __tun_detach+0xd5b/0x1000 drivers/net/tun.c:726
 tun_detach drivers/net/tun.c:743 [inline]
 tun_chr_close+0xe0/0x180 drivers/net/tun.c:3450
 __fput+0x2e5/0x8d0 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x14a/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x412b61
Code: 01 00 00 64 48 8b 04 25 f8 ff ff ff 48 8b 40 30 48 8b 80 98 00 00 00 48 85 c0 74 15 48 8b 08 48 39 d1 77 0d 48 8b 40 08 48 39 <c2> 0f 82 fb 00 00 00 48 8b 05 31 d5 33 01 48 85 c0 0f 84 e2 00 00
RSP: 002b:00007ffd7af65e60 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412b61
RDX: 0000001b2e320000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000001 R08: 000000000536b032 R09: 000000000536b036
R10: 00007ffd7af65f40 R11: 0000000000000293 R12: 000000000073c900
R13: 000000000073c900 R14: 000000000023c2f7 R15: 000000000073bfac
INFO: task syz-executor.4:9841 blocked for more than 144 seconds.
      Not tainted 5.1.0-rc5+ #99
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D26760  9841   9288 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 __netlink_dump_start+0x10c/0x7e0 net/netlink/af_netlink.c:2325
 netlink_dump_start include/linux/netlink.h:226 [inline]
 rtnetlink_rcv_msg+0x73f/0xb00 net/core/rtnetlink.c:5158
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2486
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5213
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1926
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:661
 ___sys_sendmsg+0x806/0x930 net/socket.c:2279
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2317
 __do_sys_sendmsg net/socket.c:2326 [inline]
 __se_sys_sendmsg net/socket.c:2324 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2324
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458da9
Code: 05 0c cc 45 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 6a 3e fd ff 48 8b 44 24 18 48 89 04 24 e8 0c 3d fd ff 48 8d 05 e5 cb <45> 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 43 3e fd ff 48 8b
RSP: 002b:00007fa6a6d33c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa6a6d346d4
R13: 00000000004c6636 R14: 00000000004daf58 R15: 00000000ffffffff
INFO: task syz-executor.4:9846 blocked for more than 144 seconds.
      Not tainted 5.1.0-rc5+ #99
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D29072  9846   9288 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
 __tun_chr_ioctl+0x3cd/0x3f40 drivers/net/tun.c:3066
 tun_chr_ioctl+0x2b/0x40 drivers/net/tun.c:3356
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458da9
Code: 05 0c cc 45 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 6a 3e fd ff 48 8b 44 24 18 48 89 04 24 e8 0c 3d fd ff 48 8d 05 e5 cb <45> 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 43 3e fd ff 48 8b
RSP: 002b:00007fa6a6d12c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000020000100 RSI: 00000000800454e1 RDI: 0000000000000005
RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa6a6d136d4
R13: 00000000004c33f5 R14: 00000000004d6830 R15: 00000000ffffffff
INFO: task syz-executor.0:9850 blocked for more than 145 seconds.
      Not tainted 5.1.0-rc5+ #99
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D28960  9850  30384 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
 sock_do_ioctl+0x254/0x300 net/socket.c:1050
 sock_ioctl+0x3f9/0x7a0 net/socket.c:1187
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458da9
Code: 05 0c cc 45 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 6a 3e fd ff 48 8b 44 24 18 48 89 04 24 e8 0c 3d fd ff 48 8d 05 e5 cb <45> 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 43 3e fd ff 48 8b
RSP: 002b:00007fddf8e6bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000003
RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fddf8e6c6d4
R13: 00000000004c229f R14: 00000000004d4b98 R15: 00000000ffffffff

Showing all locks held in the system:
4 locks held by kworker/u4:3/62:
 #0: 00000000cd3adceb ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 00000000cd3adceb ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000cd3adceb ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: 00000000cd3adceb ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: 00000000cd3adceb ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline]
 #0: 00000000cd3adceb ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0: 00000000cd3adceb ((wq_completion)netns){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240
 #1: 000000002c156e08 (net_cleanup_work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244
 #2: 00000000b5cf08f5 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0x960 net/core/net_namespace.c:519
 #3: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
1 lock held by khungtaskd/1042:
 #0: 00000000b0bfdbe1 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5056
1 lock held by rsyslogd/7510:
 #0: 000000006b9dfdb3 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801
2 locks held by getty/7601:
 #0: 0000000048779901 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000fa721c69 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7602:
 #0: 0000000040de06b3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 0000000034263807 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7603:
 #0: 0000000031738198 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 000000007dc3641f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7604:
 #0: 00000000d6d95452 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000aad4a73e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7605:
 #0: 00000000e6fd100c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 0000000074e51280 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7606:
 #0: 00000000e1ef6cb5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000ebdbcabb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7607:
 #0: 000000009f4dbc1f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000f3a1e182 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
3 locks held by kworker/1:12/18825:
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240
 #1: 00000000f0a7de13 (deferred_process_work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244
 #2: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
3 locks held by kworker/1:13/21757:
 #0: 00000000a9f2ad1d ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 00000000a9f2ad1d ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000a9f2ad1d ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: 00000000a9f2ad1d ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: 00000000a9f2ad1d ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline]
 #0: 00000000a9f2ad1d ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0: 00000000a9f2ad1d ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240
 #1: 00000000cb821bf5 ((addr_chk_work).work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244
 #2: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
3 locks held by kworker/1:16/21923:
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0: 00000000b63623e3 ((wq_completion)events){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240
 #1: 00000000178823b6 ((linkwatch_work).work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244
 #2: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
2 locks held by syz-executor.5/9807:
 #0: 00000000b5cf08f5 (pernet_ops_rwsem){++++}, at: copy_net_ns+0x1c0/0x340 net/core/net_namespace.c:434
 #1: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
1 lock held by syz-executor.2/9819:
 #0: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
1 lock held by syz-executor.1/9822:
 #0: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
1 lock held by syz-executor.4/9841:
 #0: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: __netlink_dump_start+0x10c/0x7e0 net/netlink/af_netlink.c:2325
1 lock held by syz-executor.4/9846:
 #0: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76
1 lock held by syz-executor.0/9850:
 #0: 00000000bbc3dd62 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76

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

NMI backtrace for cpu 0
CPU: 0 PID: 1042 Comm: khungtaskd Not tainted 5.1.0-rc5+ #99
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
 watchdog+0x9b7/0xec0 kernel/hung_task.c:288
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1: