INFO: task kworker/0:2H:5080 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2H    state:D stack:26504 pid:5080  tgid:5080  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: kblockd blk_mq_requeue_work
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_timeout+0x158/0x2c0
 nbd_queue_rq+0x857/0x1100
 blk_mq_dispatch_rq_list+0xa70/0x1910
 __blk_mq_sched_dispatch_requests+0xdcc/0x1600
 blk_mq_sched_dispatch_requests+0xd7/0x190
 blk_mq_run_hw_queue+0x348/0x4f0
 blk_mq_run_hw_queues+0x26c/0x3f0
 blk_mq_requeue_work+0x71c/0x780
 process_scheduled_works+0xb5d/0x1860
 worker_thread+0xa53/0xfc0
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/0:2H/5080:
 #0: ffff8881026cad40 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc9000277fc40 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffff88810b1a9498 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x31f/0x4f0
 #3: ffff888119998778 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xc6/0x1100
2 locks held by getty/5443:
 #0: ffff888115d830a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
1 lock held by udevd/5611:
 #0: ffff88810b3b6350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
4 locks held by syz.1.3555/19148:
 #0: ffffffff8fe3fb28 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffff88801c9d9128 (&dev->mutex){....}-{4:4}, at: devlink_get_from_attrs_lock+0x34a/0x490
 #2: ffff88801c96f258 (&devlink->lock_key){+.+.}-{4:4}, at: devlink_get_from_attrs_lock+0x360/0x490
 #3: ffffffff8e9630a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
2 locks held by syz.0.3560/19160:
 #0: ffffffff9032b0a0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff8e962f78 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580

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

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+0x389/0x470
 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: 19148 Comm: syz.1.3555 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:timerqueue_linked_add+0xe1/0x2e0
Code: 4d 8b 3f 4d 85 ff 74 0a e8 7c 2d 21 f6 4d 89 fe eb a4 4c 8d 3c dd 08 00 00 00 4d 01 f7 4d 39 ec 0f 8d a2 00 00 00 4d 8d 66 18 <4c> 89 e0 48 c1 e8 03 80 3c 28 00 4c 8b 6c 24 08 74 08 4c 89 e7 e8
RSP: 0018:ffffc90000a08d58 EFLAGS: 00000093
RAX: 1ffff110478c7713 RBX: 0000000000000001 RCX: ffff8881116c9d80
RDX: 0000000000010000 RSI: 0000004e5f894122 RDI: 0000004e28aee680
RBP: dffffc0000000000 R08: ffffffff9030bcf7 R09: 1ffffffff206179e
R10: dffffc0000000000 R11: fffffbfff206179f R12: ffff88823c63b8a0
R13: 0000004e5f894122 R14: ffff88823c63b888 R15: ffff88823c63b898
FS:  00007fd4a570f6c0(0000) GS:ffff8882a928a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005591c7a52000 CR3: 000000010aa96000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 enqueue_hrtimer+0x18e/0x2c0
 __hrtimer_run_queues+0x4d2/0xa20
 hrtimer_interrupt+0x44b/0x950
 __sysvec_apic_timer_interrupt+0x102/0x430
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:vprintk_emit+0x45d/0x560
Code: 0f 84 44 ff ff ff e8 32 28 21 00 fb eb 44 e8 2a 28 21 00 e8 e5 28 04 0a 4d 85 f6 74 94 e8 1b 28 21 00 fb 48 c7 c7 c0 f1 94 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 18
RSP: 0018:ffffc900042fe6e0 EFLAGS: 00000287
RAX: ffffffff81a49c45 RBX: ffffffff81a49abf RCX: 0000000000080000
RDX: ffffc9000869a000 RSI: 000000000003a0e7 RDI: ffffffff8e94f1c0
RBP: ffffc900042fe790 R08: ffffffff9030bcf7 R09: 1ffffffff206179e
R10: dffffc0000000000 R11: fffffbfff206179f R12: 0000000000000000
R13: 0000000000000055 R14: 0000000000000200 R15: 1ffff9200085fce0
 dev_vprintk_emit+0x355/0x420
 dev_printk_emit+0xee/0x140
 __netdev_printk+0x3e1/0x480
 netdev_info+0x11e/0x180
 nsim_udp_tunnel_unset_port+0x2d0/0x530
 __udp_tunnel_nic_device_sync+0xb9f/0x1580
 udp_tunnel_nic_flush+0x2cc/0x670
 udp_tunnel_nic_netdevice_event+0xfb2/0x17d0
 notifier_call_chain+0x1ad/0x3d0
 unregister_netdevice_many_notify+0x17a5/0x22c0
 unregister_netdevice_queue+0x31f/0x360
 nsim_destroy+0x277/0x7f0
 __nsim_dev_port_del+0x14f/0x200
 nsim_dev_reload_destroy+0x288/0x490
 nsim_dev_reload_down+0x8a/0xc0
 devlink_reload+0x1eb/0x8c0
 devlink_nl_reload_doit+0xaaa/0xc80
 genl_family_rcv_msg_doit+0x22a/0x330
 genl_rcv_msg+0x61c/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x75c/0x8e0
 netlink_sendmsg+0x813/0xb40
 ____sys_sendmsg+0x972/0x9f0
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1bd/0x2a0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd4a479ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd4a570f028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd4a4a15fa0 RCX: 00007fd4a479ce59
RDX: 0000000000000000 RSI: 0000200000000080 RDI: 0000000000000003
RBP: 00007fd4a4832d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd4a4a16038 R14: 00007fd4a4a15fa0 R15: 00007ffc996bcbe8
 </TASK>
