INFO: task kworker/u10:4:65 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u10:4   state:D stack:21544 pid:65    tgid:65    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_unbound linkwatch_event
Call Trace:
 <TASK>
 __schedule+0x17d4/0x5820
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c1/0x1550
 linkwatch_event+0xe/0x60
 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 dhcpcd:5341 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:21384 pid:5341  tgid:5341  ppid:5340   task_flags:0x400140 flags:0x00080800
Call Trace:
 <TASK>
 __schedule+0x17d4/0x5820
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c1/0x1550
 rtnl_dump_ifinfo+0xa74/0x14a0
 rtnl_dumpit+0xcc/0x200
 netlink_dump+0x711/0xee0
 netlink_recvmsg+0x683/0xa50
 sock_recvmsg+0x196/0x1e0
 ____sys_recvmsg+0x1e6/0x4a0
 ___sys_recvmsg+0x213/0x5a0
 __x64_sys_recvmsg+0x1ae/0x290
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0677ae491e
RSP: 002b:00007ffeaf126fb8 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007ffeaf1280e0 RCX: 00007f0677ae491e
RDX: 0000000000000000 RSI: 00007ffeaf128000 RDI: 0000000000000008
RBP: 00007ffeaf128070 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000d9 R11: 0000000000000246 R12: 0000000000000c7c
R13: 00007ffeaf127fe4 R14: 00007ffeaf128000 R15: 00007ffeaf127ff0
 </TASK>
INFO: task kworker/1:21:10633 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:21    state:D stack:23632 pid:10633 tgid:10633 ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events switchdev_deferred_process_work
Call Trace:
 <TASK>
 __schedule+0x17d4/0x5820
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c1/0x1550
 switchdev_deferred_process_work+0xe/0x20
 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 syz-executor:14434 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:25544 pid:14434 tgid:14434 ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d4/0x5820
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c1/0x1550
 ops_undo_list+0x28e/0x8d0
 setup_net+0x2f6/0x350
 copy_net_ns+0x4f9/0x720
 create_new_namespaces+0x3f0/0x6b0
 unshare_nsproxy_namespaces+0x149/0x190
 ksys_unshare+0x5a7/0x950
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f96c9b9f427
RSP: 002b:00007ffe768920d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f96c9e25f40 RCX: 00007f96c9b9f427
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f96c9e267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffe76892318 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:14438 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:25544 pid:14438 tgid:14438 ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d4/0x5820
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c1/0x1550
 ip_tunnel_init_net+0x2d5/0x820
 vti_init_net+0x2f/0x100
 ops_init+0x35d/0x5d0
 setup_net+0x118/0x350
 copy_net_ns+0x4f9/0x720
 create_new_namespaces+0x3f0/0x6b0
 unshare_nsproxy_namespaces+0x149/0x190
 ksys_unshare+0x5a7/0x950
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe320f9f427
RSP: 002b:00007fff77dc97b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fe321225f40 RCX: 00007fe320f9f427
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007fe3212267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007fff77dc99f8 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
locks held by kworker/u8:0/12: 3, on CPU#0:
 #0: ffff88811208a140 ((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: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30
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: unwind_next_frame+0x8f/0x2550
 #3: ffffffff8ed5c6e0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550
locks held by khungtaskd/35: 1, last CPU#0:
 #0: ffffffff8ed5c6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
locks held by kworker/u10:1/37: 3, last CPU#0:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90000ad7c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff8881bcb94258 (&devlink->lock_key#3){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40
locks held by kworker/u10:4/65: 3, on CPU#1:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90001777c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
locks held by dhcpcd/5341: 2, on CPU#1:
 #0: ffff8881bac196e8 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xe7/0xee0
 #1: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dump_ifinfo+0xa74/0x14a0
locks held by getty/5424: 2, on CPU#0:
 #0: ffff888114df90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034832e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360
locks held by kworker/u8:2/5628: 6, last CPU#0:
 #0: ffff8881012d5940 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000505fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff902412e8 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810
 #3: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x28e/0x8d0
 #4: ffffffff8eeabbb0 (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/1:21/10633: 3, on CPU#1:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc9000c477c40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20
locks held by syz-executor/14434: 2, on CPU#0:
 #0: ffffffff902412e8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4e2/0x720
 #1: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x28e/0x8d0
locks held by syz-executor/14438: 2, on CPU#1:
 #0: ffffffff902412e8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4e2/0x720
 #1: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2d5/0x820
locks held by syz-executor/14446: 2, on CPU#1:
 #0: ffffffff902412e8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4e2/0x720
 #1: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x28e/0x8d0
locks held by syz-executor/14478: 1, on CPU#0:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/14483: 1, on CPU#0:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/14489: 1, on CPU#0:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/14495: 1, on CPU#0:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/14500: 1, on CPU#0:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/14506: 1, on CPU#0:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/14513: 2, last CPU#0:
 #0: ffff88810c481078 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0
 #1: ffffffff8ed5c6e0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240
locks held by syz-executor/14514: 1, on CPU#0:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/14520: 1, on CPU#0:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/14525: 1, on CPU#1:
 #0: ffffffff9024fb40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0

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

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: 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:ip6_ignore_linkdown+0x36/0x140
Code: 00 00 fc ff df e8 5a 4f 38 f7 48 81 c3 c0 00 00 00 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 2d 17 a8 f7 48 8b 1b <e8> c5 55 53 01 89 c5 31 ff 89 c6 e8 2a 54 38 f7 85 ed 74 10 e8 71
RSP: 0018:ffffc90000a17698 EFLAGS: 00000246
RAX: 1ffff11037753018 RBX: ffff8881bb9f1000 RCX: ffff888102ed8000
RDX: 8000000000000100 RSI: 0000000000000100 RDI: ffff8881bba98000
RBP: 1ffff1103670f599 R08: 0000000000000100 R09: ffffc90000a179d0
R10: ffffc90000a17820 R11: fffff52000142f06 R12: 0000000000000003
R13: ffff8881b387acc8 R14: dffffc0000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8882a8cde000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f37d8557e20 CR3: 000000000eb48000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 find_match+0x9c/0xb40
 __find_rr_leaf+0x243/0x740
 fib6_table_lookup+0x3c6/0xae0
 ip6_pol_route+0x229/0x14d0
 fib6_rule_action+0x9d7/0xc00
 fib_rules_lookup+0x770/0xeb0
 fib6_rule_lookup+0x1a0/0x730
 ip6_route_input+0x78d/0xb20
 ip6_rcv_finish+0x141/0x280
 ip_sabotage_in+0x1e1/0x270
 nf_hook_slow+0xc5/0x220
 NF_HOOK+0x21f/0x3c0
 netif_receive_skb+0x278/0xbf0
 NF_HOOK+0xa4/0x3a0
 br_handle_frame_finish+0x1136/0x1950
 br_nf_hook_thresh+0x3dd/0x4c0
 br_nf_pre_routing_finish_ipv6+0x90c/0xc40
 br_nf_pre_routing_ipv6+0x382/0x6f0
 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 fd 52 be f5 f7 c3 00 02 00 00 74 05 e8 30 8a ea 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> 94 6c af f5 65 48 8b 05 5c b2 ae 07 48 85 c0 74 18 5b 41 5e c3
RSP: 0018:ffffc90000157ca8 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000206 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8e47651f RDI: 0000000000000001
RBP: ffffc90000157e18 R08: ffffffff907a397f R09: 1ffffffff20f472f
R10: dffffc0000000000 R11: fffffbfff20f4730 R12: 0000000000000002
R13: ffff888102ed8000 R14: ffffffff9ad2cfe0 R15: dffffc0000000000
 nbcon_kthread_func+0x6c4/0x880
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
