INFO: task dhcpcd:5336 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:21384 pid:5336  tgid:5336  ppid:5335   task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 __schedule+0x17db/0x58f0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c1/0x1550
 inet_rtm_deladdr+0x1cd/0x7a0
 rtnetlink_rcv_msg+0x802/0xc00
 netlink_rcv_skb+0x226/0x4a0
 netlink_unicast+0x7bd/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 ____sys_sendmsg+0x54e/0x850
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1b1/0x290
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9d08abfa4b
RSP: 002b:00007ffe08e21048 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9d089e76c0 RCX: 00007f9d08abfa4b
RDX: 0000000000000000 RSI: 00007ffe08e351f8 RDI: 0000000000000011
RBP: 0000000000000011 R08: 0000000000000000 R09: 00007ffe08e351f8
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff
R13: 00007ffe08e351f8 R14: 0000000000000020 R15: 0000000000000001
 </TASK>
INFO: task kworker/u8:5:9775 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:5    state:D stack:22976 pid:9775  tgid:9775  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
 <TASK>
 __schedule+0x17db/0x58f0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c1/0x1550
 addrconf_verify_work+0x19/0x30
 process_scheduled_works+0xc3d/0x1630
 worker_thread+0xa47/0xfb0
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Showing all locks held in the system:
locks held by kworker/0:0/9: 3, on CPU#0:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900000e7c40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff902517c0 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20
locks held by kworker/u8:0/12: 4, last CPU#1:
 #0: ffff88810c403140 ((wq_completion)krds_cp_wq#3/5){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000117c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881077c4380 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff8881094c1d60 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30
locks held by kworker/u8:1/13: 4, last CPU#1:
 #0: ffff888119501140 ((wq_completion)krds_cp_wq#3/0){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000127c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881077c5280 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff88810d015360 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30
locks held by pr/ttyS0/16: 1, last CPU#1:
 #0: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60
locks held by khungtaskd/35: 1, last CPU#0:
 #0: ffffffff8ed5c760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
locks held by kworker/u10:2/68: 2, last CPU#1:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900017a7c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by dhcpcd/5336: 1, on CPU#0:
 #0: ffffffff902517c0 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_deladdr+0x1cd/0x7a0
locks held by getty/5421: 2, on CPU#1:
 #0: ffff8881189fb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034762e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360
locks held by kworker/u8:2/5458: 4, last CPU#1:
 #0: ffff88811b336940 ((wq_completion)krds_cp_wq#16/1){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90004217c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888033c5d880 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff88810c6d45e0 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30
locks held by kworker/u8:3/5701: 4, last CPU#1:
 #0: ffff888012a17140 ((wq_completion)krds_cp_wq#16/0){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90004f37c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888033c5db80 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff88810cd18fe0 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30
locks held by kworker/u10:7/6718: 2, last CPU#1:
 #0: ffff8881604a3140 ((wq_completion)wg-kex-wg2#3){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90003d4fc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by kworker/0:10/7459: 2, last CPU#0:
 #0: ffff888100069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90003a0fc40 ((work_completion)(&(&tbl->gc_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by kworker/u8:4/8735: 3, last CPU#1:
 #0: ffff888116c7b140 ((wq_completion)krds_cp_wq#16/4){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000404fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888033c5cf80 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by kworker/u8:5/9775: 3, on CPU#1:
 #0: ffff88811531f940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90006697c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff902517c0 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30
locks held by kworker/u8:6/9776: 2, last CPU#1:
 #0: ffff888115af5940 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900063cfc40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by kworker/u8:7/9777: 3, last CPU#1:
 #0: ffff8881a3694140 ((wq_completion)krds_cp_wq#2/0){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000629fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881bbcb5280 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by kworker/u10:24/10127: 3, on CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90007fafc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff902517c0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
locks held by kworker/u8:9/12647: 4, last CPU#1:
 #0: ffff8881168c1940 ((wq_completion)krds_cp_wq#6/0){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90009f0fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888104b56180 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff888033029c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: __inet_bind+0x3b0/0xaa0
locks held by kworker/u9:41/16913: 3, last CPU#1:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900046afc40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881a5ef5258 (&devlink->lock_key#2){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/u8:10/24356: 3, last CPU#1:
 #0: ffff88810c405940 ((wq_completion)krds_cp_wq#3/7){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90003f4fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888104b57c80 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by syz-executor/25338: 1, on CPU#0:
 #0: ffffffff902517c0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
locks held by kworker/u8:11/26555: 3, last CPU#1:
 #0: ffff88803aea6940 ((wq_completion)krds_cp_wq#16/3){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90004effc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888033c5d280 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by kworker/u8:12/26556: 4, last CPU#1:
 #0: ffff88810c401140 ((wq_completion)krds_cp_wq#3/2){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000497fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881077c4c80 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff88810c6d1d60 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30
locks held by kworker/u8:14/26581: 5, last CPU#1:
 #0: ffff88810c404140 ((wq_completion)krds_cp_wq#3/4){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000395fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881077c4680 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff88810d0145e0 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30
 #4: ffff88823c628298 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_rearm_deferred+0x99/0x4b0
locks held by kworker/u8:15/26582: 3, last CPU#1:
 #0: ffff88810c401940 ((wq_completion)krds_cp_wq#3/6){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90003d2fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881077c4080 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by kworker/u8:17/26584: 4, last CPU#1:
 #0: ffff88803aea5940 ((wq_completion)krds_cp_wq#16/2){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000348fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888033c5d580 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff88810c6d60e0 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30
locks held by kworker/u8:18/26585: 3, last CPU#1:
 #0: ffff88810c400940 ((wq_completion)krds_cp_wq#3/3){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000391fc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881077c4980 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by kworker/u8:19/26586: 5, last CPU#1:
 #0: ffff8881b82b0140 ((wq_completion)krds_cp_wq#16/7){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900061afc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888033c5c680 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
 #3: ffff88810cd1c5e0 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30
 #4: ffffffff8ed5c760 (rcu_read_lock){....}-{1:3}, at: __inet6_bind+0x49b/0xf30
locks held by kworker/u8:20/26588: 3, last CPU#1:
 #0: ffff8881b82b6140 ((wq_completion)krds_cp_wq#16/6){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90003bdfc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888033c5c980 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by kworker/u8:21/26591: 3, last CPU#1:
 #0: ffff888119506940 ((wq_completion)krds_cp_wq#3/1){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900048ffc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881077c4f80 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by kworker/u8:22/26594: 3, last CPU#1:
 #0: ffff8881b82b7940 ((wq_completion)krds_cp_wq#16/5){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000a87c40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888033c5cc80 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920
locks held by syz-executor/26601: 1, on CPU#1:
 #0: ffffffff902517c0 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/26603: 2, on CPU#0:
 #0: ffff888115f58ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x22a/0x5b0
 #1: ffffffff8ed62b28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17d/0x390
 sys_info+0x135/0x170
 watchdog+0xfd7/0x1030
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 26581 Comm: kworker/u8:14 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: krds_cp_wq#3/4 rds_connect_worker
RIP: 0010:native_apic_msr_write+0x39/0x50
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 cc cc cc cc cc 89 f6 31 d2 e9 66 0d a6 03 66 0f 1f 44 00
RSP: 0018:ffffc90000a18d30 EFLAGS: 00000046
RAX: 000000000004c611 RBX: ffff88823c623c80 RCX: 0000000000000838
RDX: 0000000000000000 RSI: 000000000004c611 RDI: 0000000000000838
RBP: ffffc90000a18df0 R08: 0000000000000100 R09: 0000000000000001
R10: 0000000000000003 R11: ffffffff81754510 R12: 000000000004c611
R13: dffffc0000000000 R14: 00000000100006b5 R15: 0000000000000020
FS:  0000000000000000(0000) GS:ffff8882a8cd6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb473971866 CR3: 000000011978a000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 lapic_next_event+0x11/0x20
 clockevents_program_event+0x385/0x630
 __hrtimer_rearm_deferred+0x36c/0x4b0
 irqentry_exit+0x8d3/0x910
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80
Code: f7 e8 0d 7f bc f5 f7 c3 00 02 00 00 74 05 e8 f0 c1 e8 f5 9c 58 a9 00 02 00 00 75 29 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 14 8e ad f5 65 48 8b 05 0c 51 ad 07 48 85 c0 74 18 5b 41 5e e9
RSP: 0018:ffffc90000a18f40 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000283 RCX: 8000000000000102
RDX: 0000000000000002 RSI: ffffffff8e474d15 RDI: 0000000000000001
RBP: 000000000000000a R08: ffffffff907a217f R09: 1ffffffff20f442f
R10: dffffc0000000000 R11: fffffbfff20f4430 R12: 0000000000000009
R13: 0000000000000008 R14: ffff88823c628280 R15: 0000000000000100
 handle_softirqs+0x226/0x860
 do_softirq+0x77/0xd0
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x140
 __inet6_bind+0x386/0xf30
 kernel_bind+0x13e/0x1c0
 rds_tcp_conn_path_connect+0x53b/0x920
 rds_connect_worker+0x1d8/0x290
 process_scheduled_works+0xc3d/0x1630
 worker_thread+0xa47/0xfb0
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
