INFO: task kworker/u8:2:5629 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:23752 pid:5629  tgid:5629  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/u8:0/12: 4, last CPU#0:
 #0: ffff8881012d5940 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000117c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff90242488 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810
 #3: ffffffff90250d00 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x28e/0x8d0
locks held by kworker/u8:1/13: 2, last CPU#1:
 #0: ffff88810d326940 ((wq_completion)bond1#2){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000127c40 ((work_completion)(&(&bond->ad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by pr/ttyS0/16: 4, last CPU#1:
 #0: ffffffff8ec362b8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60
 #1: ffffffff8ed5c6e0 (rcu_read_lock){....}-{1:3}, at: process_backlog+0x3de/0x18b0
 #2: ffffffff8ed5c6e0 (rcu_read_lock){....}-{1:3}, at: __refill_objects_node+0x86/0x600
 #3: ffffffff8ed5c6e0 (rcu_read_lock){....}-{1:3}, at: NF_HOOK+0x9e/0x3c0
locks held by kworker/1:0/25: 2, last CPU#1:
 #0: ffff88810e9e0d40 ((wq_completion)wg-crypt-wg1#6){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900001f7c40 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by kworker/u10:0/28: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000a37c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881b3e65258 (&devlink->lock_key#9){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by khungtaskd/34: 1, last CPU#0:
 #0: ffffffff8ed5c6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
locks held by kworker/1:1/47: 3, on CPU#1:
 #0: ffff888100069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000b77c40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff90250d00 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xac/0x1110
locks held by kworker/u9:2/53: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000bf7c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88810c825258 (&devlink->lock_key#10){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/u9:3/65: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90001777c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888177889258 (&devlink->lock_key#8){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/u9:4/66: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90001797c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88811b3b4258 (&devlink->lock_key#3){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/u10:2/71: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900017d7c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881792807a0 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420
locks held by kworker/u10:3/87: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000231fc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881730307a0 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420
locks held by kworker/1:2/807: 6, last CPU#1:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900045bfc40 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffc900045bf770 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_atomic_helper_dirtyfb+0x106/0xfd0
 #3: ffffc900045bf798 (crtc_ww_class_mutex){+.+.}-{4:4}, at: drm_atomic_helper_dirtyfb+0x106/0xfd0
 #4: ffffffff8eeabc30 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
 #5: ffffffff8ed5c6e0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550
locks held by kworker/u10:8/1110: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900066f7c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88816e547258 (&devlink->lock_key){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/u10:11/1113: 4, last CPU#0:
 #0: ffff8881b475a940 ((wq_completion)wg-kex-wg1#5){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90006727c40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88816a7e9440 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x12e/0x810
 #3: ffff88816a685270 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x13f/0x810
locks held by kworker/u10:13/1115: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90006747c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88810f0bd258 (&devlink->lock_key#7){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by jbd2/sda1-8/5008: 1, last CPU#0:
 #0: ffffffff8eeabc30 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by syslogd/5028: 2, last CPU#0:
 #0: ffffffff8f4ef878 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_path_perm+0x251/0x560
 #1: ffffffff8eeabc30 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by udevd/5046: 4, last CPU#0:
 #0: ffffffff8ee35c10 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x10f/0x480
 #1: ffff88816f7836b8 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0
 #2: ffff888168049d38 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0
 #3: ffffffff8eeabc30 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by dhcpcd/5341: 2, last CPU#0:
 #0: ffffffff8f4ef878 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_path_number_perm+0x219/0x5f0
 #1: ffffffff8eeabc30 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by dhcpcd/5342: 4, last CPU#0:
 #0: ffffffff8ee35c10 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x10f/0x480
 #1: ffff88810d1769b8 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0
 #2: ffff88816804d038 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0
 #3: ffffffff8eeabc30 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by getty/5425: 2, on CPU#0:
 #0: ffff88816acbc0a0 (&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/u8:2/5629: 3, on CPU#0:
 #0: ffff888177b3d940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90004c17c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff90250d00 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30
locks held by kworker/1:7/5672: 2, last CPU#1:
 #0: ffff888100069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90004f27c40 ((gc_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by syz-executor/8501: 4, last CPU#0:
 #0: ffffffff8ee35c10 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x10f/0x480
 #1: ffff88816804e9b8 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0
 #2: ffff88816abf83b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0
 #3: ffffffff8eeabc30 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by kworker/u9:5/9763: 3, last CPU#1:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90004a07c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88816de5f258 (&devlink->lock_key#4){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by syz-executor/10995: 3, on CPU#1:
 #0: ffff8881adcacea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x22a/0x5b0
 #1: ffff8881adcac0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x61f/0x10c0
 #2: ffffffff8ed62aa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
locks held by kworker/u8:5/11069: 3, last CPU#0:
 #0: ffff888120ffa140 ((wq_completion)krds_cp_wq#2/0){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900206ffc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88810c6fea60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_close+0x1d/0x110
locks held by kworker/1:9/11156: 2, last CPU#1:
 #0: ffff88810dd81940 ((wq_completion)wg-crypt-wg0#6){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900200bfc40 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by syz.3.1306/11527: 2, on CPU#1:
 #0: ffffffff90242488 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x524/0x780
 #1: ffffffff90250d00 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2d5/0x820
locks held by syz-executor/11533: 4, last CPU#0:
 #0: ffff88817ac0c460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff8881bc00d510 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: chmod_common+0x186/0x470
 #2: ffffffff8f4ef878 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_path_number_perm+0x219/0x5f0
 #3: ffffffff8eeabc30 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by syz-executor/11534: 1, last CPU#0:
 #0: ffff88816c7f94e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: bprm_execve+0xbc/0x1590
locks held by kworker/u8:7/11535: 2, last CPU#0:
 #0: ffff88817830f940 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900098b7c40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 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: 16 Comm: pr/ttyS0 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
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x80
Code: 8b 3d b4 a9 ac 0c 48 89 de 5b e9 73 4b 64 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0d 48 a9 cc 11 65 48 8b 15 48 a9 cc 11 f7 c2 00 01 00 ff
RSP: 0018:ffffc90000a186f8 EFLAGS: 00000286
RAX: ffffffff89ac19c9 RBX: 0000000000000000 RCX: 0000000000000102
RDX: ffff888160416dc0 RSI: ffffffff8c6d9260 RDI: ffffffff8c6d9220
RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
R10: ffff8881c4d99c00 R11: ffffffff8ed5c6e0 R12: 0000000000000000
R13: ffff8881c4d99c00 R14: 1ffff92000143124 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8882a8cda000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdff07f9458 CR3: 000000000eb48000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 skb_ext_add+0x159/0x8e0
 br_nf_pre_routing_ipv6+0x134/0x6f0
 br_handle_frame+0x127f/0x1510
 __netif_receive_skb_core+0x989/0x30c0
 process_backlog+0x727/0x18b0
 __napi_poll+0xaa/0x330
 net_rx_action+0x61d/0xf50
 handle_softirqs+0x226/0x860
 __irq_exit_rcu+0xcb/0x220
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80
Code: f7 e8 ed 43 bd f5 f7 c3 00 02 00 00 74 05 e8 e0 7d e9 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> 84 5d ae f5 65 48 8b 05 9c e1 ad 07 48 85 c0 74 18 5b 41 5e c3
RSP: 0018:ffffc90000157ca8 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000206 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8e473cbb RDI: 0000000000000001
RBP: ffffc90000157e18 R08: ffffffff907a127f R09: 1ffffffff20f424f
R10: dffffc0000000000 R11: fffffbfff20f4250 R12: 0000000000000002
R13: ffff888102ed8000 R14: ffffffff9ad31080 R15: dffffc0000000000
 nbcon_kthread_func+0x6c4/0x880
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
