INFO: task kworker/u8:2:5827 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:24448 pid:5827  tgid:5827  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 __schedule+0x1585/0x5340
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 addrconf_dad_work+0x11e/0x14c0
 process_scheduled_works+0xb02/0x1830
 worker_thread+0xa50/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task syz-executor:6932 blocked for more than 147 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:25664 pid:6932  tgid:6932  ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1585/0x5340
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 ip_tunnel_init_net+0x2d7/0x840
 ops_init+0x35c/0x5c0
 setup_net+0x118/0x340
 copy_net_ns+0x50e/0x730
 create_new_namespaces+0x3e7/0x6a0
 unshare_nsproxy_namespaces+0x11a/0x160
 ksys_unshare+0x51d/0x930
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6c56f9da67
RSP: 002b:00007ffcee9cd808 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f6c57215f40 RCX: 00007f6c56f9da67
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f6c572167b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffcee9cda48 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:6938 blocked for more than 150 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:24896 pid:6938  tgid:6938  ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1585/0x5340
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 register_netdevice_notifier_net+0x1a/0xa0
 ops_init+0x35c/0x5c0
 setup_net+0x118/0x340
