INFO: task kworker/u8:4:7751 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4    state:D stack:23584 pid:7751  tgid:7751  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_timeout+0xc0/0x2c0
 wait_for_completion+0x2ca/0x5e0
 __flush_work+0xa63/0xca0
 unregister_netdevice_many_notify+0xfe1/0x2150
 ops_undo_list+0x391/0x8d0
 cleanup_net+0x572/0x810
 process_scheduled_works+0xa8e/0x14e0
 worker_thread+0xa47/0xfb0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task syz-executor:5930 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:25584 pid:5930  tgid:5930  ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 ib_get_eth_speed+0x173/0x7f0
 siw_query_port+0x3c/0x4a0
 ib_setup_port_attrs+0x294/0x2420
 add_one_compat_dev+0x446/0x650
 rdma_dev_init_net+0x243/0x2f0
 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+0x57d/0xa00
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcd9399f3a7
RSP: 002b:00007ffec3d216b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fcd93c25f40 RCX: 00007fcd9399f3a7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007fcd93c267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffec3d218f8 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:5931 blocked for more than 144 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:25624 pid:5931  tgid:5931  ppid:1      task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_timeout+0xc0/0x2c0
 wait_for_completion+0x2ca/0x5e0
 __synchronize_srcu+0x23b/0x2f0
 hci_unregister_dev+0x148/0x5b0
 vhci_release+0x16d/0x1c0
 __fput+0x418/0xa50
 task_work_run+0x1d9/0x270
 do_exit+0x73a/0x2360
 do_group_exit+0x22d/0x2f0
 get_signal+0x121b/0x12c0
 arch_do_signal_or_restart+0xbb/0x860
 exit_to_user_mode_loop+0x104/0x730
 do_syscall_64+0x353/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7d1f19f3a7
RSP: 002b:00007ffd3e107b48 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: 0000000000000000 RBX: 00007f7d1f425f40 RCX: 00007f7d1f19f3a7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f7d1f4267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffd3e107d88 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:5960 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:25480 pid:5960  tgid:5960  ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 ib_get_eth_speed+0x173/0x7f0
 rxe_query_port+0x93/0x3d0
 ib_query_port+0x16e/0x830
 ib_setup_port_attrs+0x294/0x2420
 add_one_compat_dev+0x446/0x650
 rdma_dev_init_net+0x243/0x2f0
 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+0x57d/0xa00
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8f2399f3a7
RSP: 002b:00007ffe485db948 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f8f23c25f40 RCX: 00007f8f2399f3a7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f8f23c267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffe485dbb88 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:5981 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:26736 pid:5981  tgid:5981  ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 inet_rtm_newaddr+0x464/0x19e0
 rtnetlink_rcv_msg+0x802/0xc00
 netlink_rcv_skb+0x226/0x4a0
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 __sys_sendto+0x408/0x5a0
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f038835e90e
RSP: 002b:00007ffeda876668 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00005555600e2500 RCX: 00007f038835e90e
RDX: 0000000000000028 RSI: 00007f0389154670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffeda8766e4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f0389154670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:5986 blocked for more than 148 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:26736 pid:5986  tgid:5986  ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 inet_rtm_newaddr+0x464/0x19e0
 rtnetlink_rcv_msg+0x802/0xc00
 netlink_rcv_skb+0x226/0x4a0
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 __sys_sendto+0x408/0x5a0
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5802b5e90e
RSP: 002b:00007fff5ac042e8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000555557f67500 RCX: 00007f5802b5e90e
RDX: 0000000000000028 RSI: 00007f5803954670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff5ac04364 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f5803954670 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
 #0: ffff88810f7e5940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #1: ffffc90000127c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #2: ffffffff90026f00 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30
1 lock held by khungtaskd/34:
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
5 locks held by kworker/u11:0/53:
 #0: ffff88816eaae140 ((wq_completion)hci1){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #1: ffffc90000bd7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #2: ffff88819bbf8ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1cb/0x3f0
 #3: ffff88819bbf80b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0xa6f/0x1190
 #4: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
4 locks held by kworker/u11:1/4990:
 #0: ffff8881a061d140 ((wq_completion)hci12#2){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #1: ffffc9000484fc40 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #2: ffff8881bfb500b8 (&hdev->lock){+.+.}-{4:4}, at: le_conn_complete_evt+0xa5/0x1580
 #3: ffffffff901ae740 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm+0x2c/0x140
1 lock held by dhcpcd/5346:
 #0: ffffffff90026f00 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65e/0xdf0
2 locks held by getty/5431:
 #0: ffff888168b1b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360
