INFO: task kworker/u8:12:3504 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:12   state:D stack:24664 pid:3504  tgid:3504  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4206