INFO: task syz-executor:6708 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:6708  tgid:6708  ppid:1      task_flags:0x400140 flags:0x00800011
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:742 (T)
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1250/0x2a7c kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7017
 __mutex_lock_common+0xd04/0x2678 kernel/locking/mutex.c:692
 __mutex_lock kernel/locking/mutex.c:776 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:828
 rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
 rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 inet6_rtm_newaddr+0x468/0xaa8 net/ipv6/addrconf.c:5027
 rtnetlink_rcv_msg+0x664/0x97c net/core/rtnetlink.c:6958
 netlink_rcv_skb+0x220/0x3fc net/netlink/af_netlink.c:2550
 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6985
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x694/0x8c4 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x648/0x930 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 __sys_sendto+0x36c/0x4f4 net/socket.c:2206
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2209
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
3 locks held by kworker/u8:0/12:
3 locks held by ksoftirqd/0/15:
1 lock held by khungtaskd/32:
 #0: ffff80008fa5b6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
3 locks held by kworker/u8:2/41:
1 lock held by pr/ttyAMA-1/43:
3 locks held by kworker/u8:9/934:
3 locks held by kworker/u8:10/1521:
 #0: ffff0000c0032148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff80009f737be0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
3 locks held by kworker/u8:13/2249:
 #0: ffff0000d5166948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a13c7be0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
2 locks held by kworker/u8:15/2892:
3 locks held by kworker/u8:18/3520:
3 locks held by kworker/u8:19/3550:
2 locks held by kworker/1:3/6184:
2 locks held by dhcpcd/6268:
3 locks held by dhcpcd/6269:
2 locks held by getty/6355:
 #0: ffff0000ceccc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff8000993c42f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfc8 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/6599:
1 lock held by syz-executor/6705:
 #0: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
1 lock held by syz-executor/6708:
 #0: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
4 locks held by syz-executor/6713:
5 locks held by syz-executor/6714:
1 lock held by syz-executor/6715:
 #0: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
2 locks held by kworker/1:8/6847:
2 locks held by syz-executor/6857:
2 locks held by udevd/6861:

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