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:24120 pid:12    tgid:12    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7f7/0x1550
 addrconf_verify_work+0x19/0x30
 process_scheduled_works+0xb5d/0x1860
 worker_thread+0xa53/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task kworker/1:7:5724 blocked for more than 151 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:7     state:D stack:24560 pid:5724  tgid:5724  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_power_efficient reg_check_chans_work
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/0:2/728:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc9000479fc40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdd00c0 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20
3 locks held by kworker/u9:5/1112:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90007407c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdd00c0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
2 locks held by syslogd/5042:
5 locks held by udevd/5060:
1 lock held by dhcpcd/5356:
5 locks held by dhcpcd/5357:
2 locks held by getty/5439:
 #0: ffff888108bf80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034762e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
3 locks held by syz-executor/5615:
5 locks held by syz-executor/5862:
1 lock held by syz.2.292/7240:
 #0: ffffffff8fdd00c0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
1 lock held by syz-executor/7272:
1 lock held by syz-executor/7275:

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

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+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x388/0x470
 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: 5615 Comm: syz-executor 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:unwind_get_return_address+0x56/0x90
Code: 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 cb 0e ba 00 48 8b 3b e8 73 da 18 00 85 c0 74 14 43 80 3c 37 00 <74> 08 48 89 df e8 b0 0e ba 00 48 8b 03 eb 02 31 c0 5b 41 5e 41 5f
RSP: 0018:ffffc900048ff028 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc900048ff090 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff8e219b45 RDI: ffffffff89723a8d
RBP: ffffc900048ff0d0 R08: ffffc900048ffcd0 R09: 0000000000000000
R10: ffffc900048ff098 R11: fffff5200091fe15 R12: ffff88816aa43b00
R13: 1ffff1102d54881e R14: dffffc0000000000 R15: 1ffff9200091fe12
FS:  000055558599d500(0000) GS:ffff8882a928d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2c0e010ff8 CR3: 0000000168c68000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 arch_stack_walk+0xfb/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __reset_page_owner+0x71/0x1f0
 __free_frozen_pages+0xbc7/0xd30
 __slab_free+0x274/0x2c0
 qlist_free_all+0x99/0x100
 kasan_quarantine_reduce+0x148/0x160
 __kasan_kmalloc+0x22/0xb0
 __kmalloc_cache_node_noprof+0x3ef/0x6b0
 __get_vm_area_node+0x13f/0x300
 __vmalloc_node_range_noprof+0x36a/0x1750
 vzalloc_noprof+0xb2/0xe0
 alloc_counters+0x64/0x5d0
 do_ip6t_get_ctl+0xabd/0x1230
 nf_getsockopt+0x26e/0x290
 ipv6_getsockopt+0x1fd/0x2b0
 do_sock_getsockopt+0x51d/0x7e0
 __x64_sys_getsockopt+0x1a4/0x240
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f720179e5aa
Code: 48 83 ec 10 89 d2 48 63 ff 45 31 c9 6a 2a 45 31 c0 31 c9 e8 d8 99 fb ff 48 83 c4 18 c3 0f 1f 00 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 e8 ff ff ff f7
RSP: 002b:00007fff33487888 EFLAGS: 00000212 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007fff33487910 RCX: 00007f720179e5aa
RDX: 0000000000000041 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007fff334878ac R09: ffffff0000000000
R10: 00007fff33487910 R11: 0000000000000212 R12: 00007f72019e9b80
R13: 00007fff334878ac R14: 0000000000000000 R15: 00007f72019eafc0
 </TASK>
