INFO: task kworker/u8:0:12 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0    state:D stack:24840 pid:12    tgid:12    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>
INFO: task kworker/1:3:5006 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:3     state:D stack:20736 pid:5006  tgid:5006  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events reg_todo
Call Trace:
 <TASK>
 __schedule+0x17db/0x58f0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c1/0x1550
 reg_process_self_managed_hints+0x8d/0x160
 reg_todo+0x8df/0xa40
 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: 3, on CPU#0:
 #0: ffff88816db22940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000117c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff90254b00 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30
locks held by kworker/u8:1/13: 2, last CPU#0:
 #0: ffff88816e558940 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000127c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by kworker/1:0/25: 2, last CPU#1:
 #0: ffff88816db4ed40 ((wq_completion)wg-crypt-wg1#2){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900001f7c40 ((work_completion)(&peer->transmit_packet_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by kworker/u9:0/27: 2, on CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000a27c40 ((work_completion)(&pool->idle_cull_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)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881bc1e0800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420
locks held by kworker/1:1/33: 3, on CPU#1:
 #0: ffff888100069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000a87c40 ((crda_timeout).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff90254b00 (rtnl_mutex){+.+.}-{4:4}, at: crda_timeout_work+0x16/0x80
locks held by khungtaskd/36: 1, last CPU#0:
 #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
locks held by kworker/u10:2/39: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000af7c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881726e0800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420
locks held by kworker/u10:3/64: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90001767c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88816ed20800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420
locks held by kworker/u10:4/65: 4, last CPU#0:
 #0: ffff8881622c1140 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90001777c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881704dc0e8 (&type->s_umount_key#33){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0
 #3: ffff8881704dac98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0
locks held by kworker/u10:5/68: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900017a7c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881bc070800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420
locks held by kworker/u9:3/168: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000325fc40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff88802045d258 (&devlink->lock_key#2){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/u9:4/621: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900041efc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881bb090800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420
locks held by kworker/u9:5/1107: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90006897c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888111e68258 (&devlink->lock_key){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/u9:7/1112: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90006907c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881bd1f3258 (&devlink->lock_key#3){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/0:3/2451: 5, last CPU#0:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90008817c40 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffc90008817770 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_atomic_helper_dirtyfb+0x106/0xfd0
 #3: ffffc90008817798 (crtc_ww_class_mutex){+.+.}-{4:4}, at: drm_atomic_helper_dirtyfb+0x106/0xfd0
 #4: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by kworker/1:2/5003: 4, last CPU#1:
 #0: ffff888100069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9002053fc40 ((work_completion)(&(&tbl->gc_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: process_backlog+0x3de/0x18b0
 #3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: NF_HOOK+0x9e/0x3c0
locks held by kworker/1:3/5006: 4, on CPU#1:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9002050fc40 (reg_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff90254b00 (rtnl_mutex){+.+.}-{4:4}, at: reg_todo+0x1c/0xa40
 #3: ffff8881bb090800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_process_self_managed_hints+0x8d/0x160
locks held by udevd/5043: 4, last CPU#0:
 #0: ffffffff8ee36650 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10a/0x480
 #1: ffff8881681f4080 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0
 #2: ffff888115d2d900 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0
 #3: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by dhcpcd/5338: 1, last CPU#0:
 #0: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by dhcpcd/5339: 4, last CPU#0:
 #0: ffffffff8ee36650 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10a/0x480
 #1: ffff8881681f0340 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0
 #2: ffff88810bedc080 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0
 #3: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by getty/5421: 2, on CPU#1:
 #0: ffff8881716330a0 (&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 sshd/5573: 3, last CPU#0:
 #0: ffff8881bcbe8260 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x21/0x50
 #1: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
 #2: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550
locks held by syz-executor/5591: 1, on CPU#1:
 #0: ffffffff90254b00 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
locks held by syz-executor/5600: 1, last CPU#0:
 #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550
locks held by syz.1.23/5768: 1, on CPU#0:
 #0: ffffffff90254b00 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
locks held by kworker/1:6/5831: 2, last CPU#1:
 #0: ffff888113ea4940 ((wq_completion)wg-kex-wg2#6){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90006817c40 ((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/u10:6/6003: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900070dfc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881ba990800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420
locks held by kworker/1:7/6007: 3, last CPU#1:
 #0: ffff888100069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90004b47c40 ((work_completion)(&(&gc_work->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: gc_worker+0x274/0x1890
locks held by syz-executor/6008: 1, last CPU#0:
 #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550
locks held by syz-executor/6013: 1, last CPU#0:
 #0: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60
locks held by syz-executor/6019: 2, last CPU#0:
 #0: ffff888113062b60 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: bprm_execve+0xbc/0x1590
 #1: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 36 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: 5003 Comm: kworker/1:2 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: events_power_efficient neigh_periodic_work
RIP: 0010:__lock_acquire+0x45f/0x2de0
Code: 2e da 0e 48 c7 c6 ee 0f 54 8e 67 48 0f b9 3a 90 31 c0 0f b6 98 c4 00 00 00 48 8b 45 20 25 ff 1f 00 00 48 0f a3 05 11 d6 f7 12 <73> 17 48 69 c0 c8 00 00 00 48 8d 88 d0 44 3c 94 84 db 75 3f e9 09
RSP: 0018:ffffc90000a186f8 EFLAGS: 00000003
RAX: 0000000000000007 RBX: 0000000000000003 RCX: 0000000000000007
RDX: 0000000000022000 RSI: 0000000000022000 RDI: 8d00000000000000
RBP: ffff8881700a8c28 R08: ffffffff817811df R09: 0000000000000000
R10: ffffc90000a189d8 R11: ffffffff81b2c450 R12: 0000000000000007
R13: ffff8881700a8bb0 R14: ffff8881700a8000 R15: ffff8881700a8000
FS:  0000000000000000(0000) GS:ffff8882a8cc7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3112426038 CR3: 0000000101304000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 lock_acquire+0x115/0x350
 unwind_next_frame+0xac/0x2550
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x40/0x50
 __kasan_slab_free+0x5c/0x80
 kmem_cache_free+0x182/0x650
 dst_destroy+0x22f/0x340
 rcu_core+0x926/0x1260
 handle_softirqs+0x226/0x860
 do_softirq+0x77/0xd0
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x140
 neigh_periodic_work+0xc23/0xe40
 process_scheduled_works+0xc3d/0x1630
 worker_thread+0xa47/0xfb0
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
