INFO: task syz.1.8682:26550 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.8682      state:D stack:25192 pid:26550 tgid:26538 ppid:5591   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17db/0x58f0
 schedule+0x164/0x2b0
 __lock_sock+0x162/0x2c0
 lock_sock_nested+0xc7/0x100
 sk_stream_wait_memory+0x8d8/0xf80
 tcp_sendmsg_locked+0x2352/0x5400
 tcp_sendmsg+0x2f/0x50
 sock_sendmsg_nosec+0x10e/0x180
 __sys_sendto+0x408/0x5a0
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f29cc79e159
RSP: 002b:00007f29ca9f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f29cca26180 RCX: 00007f29cc79e159
RDX: 000000006fc50de5 RSI: 0000200000000900 RDI: 0000000000000008
RBP: 00007f29cc83506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000092 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f29cca26218 R14: 00007f29cca26180 R15: 00007ffdbfa23488
 </TASK>

Showing all locks held in the system:
locks held by kworker/0:0/9: 1, last CPU#0:
 #0: ffffffff8ed5c8e0 (rcu_read_lock){....}-{1:3}, at: process_scheduled_works+0x97a/0x1630
locks held by khungtaskd/36: 1, last CPU#0:
 #0: ffffffff8ed5c8e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
locks held by dhcpcd/5339: 1, on CPU#0:
 #0: ffffffff902533a0 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x2fb/0x1c50
locks held by getty/5421: 2, on CPU#0:
 #0: ffff8881141210a0 (&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/u8:4/6978: 4, on CPU#0:
 #0: ffff8881012d5940 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc900036dfc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff90244b48 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810
 #3: ffffffff902533a0 (rtnl_mutex){+.+.}-{4:4}, at: cfg802154_pernet_exit+0x18/0xc0
locks held by kworker/0:1/25474: 4, last CPU#0:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90006a47c40 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffff888106ed7270 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_damage_work+0x15b/0xf20
 #3: ffff8881057e0128 (&dev->master_mutex){+.+.}-{4:4}, at: drm_master_internal_acquire+0x20/0x80
locks held by kworker/u9:8/25581: 3, on CPU#1:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90003a7fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #2: ffffffff902533a0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
locks held by kworker/u8:6/26057: 2, last CPU#0:
 #0: ffff8881113cf940 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
 #1: ffffc90006d77c40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630
locks held by syz.1.8682/26550: 1, on CPU#0:
 #0: ffff88810f55b660 (sk_lock-AF_INET){+.+.}-{0:0}, at: sk_stream_wait_memory+0x8d8/0xf80
locks held by syz.1.8682/26551: 3, last CPU#1:
 #0: ffff88810f55b660 (sk_lock-AF_INET){+.+.}-{0:0}, at: sk_wait_data+0x301/0x4d0
 #1: ffffffff8ed5c8e0 (rcu_read_lock){....}-{1:3}, at: __ip_queue_xmit+0x65/0x1b10
 #2: ffffffff8ed5c8e0 (rcu_read_lock){....}-{1:3}, at: ip_output+0x5a/0x450
locks held by syz-executor/26829: 2, on CPU#0:
 #0: ffffffff8f9903a8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff902533a0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc1d/0x1c30
locks held by syz-executor/26963: 1, on CPU#0:
 #0: ffffffff902533a0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc1d/0x1c30
locks held by syz.3.8783/26988: 1, last CPU#1:
 #0: ffffffff902533a0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
locks held by syz-executor/27000: 1, on CPU#1:
 #0: ffffffff902533a0 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0
locks held by syz-executor/27007: 1, on CPU#1:
 #0: ffffffff902533a0 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0

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

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: 26988 Comm: syz.3.8783 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:zap_class+0x11f/0x330
Code: 75 00 41 f6 c6 fc 74 e7 41 c1 ee 08 4a 8d 1c 75 d0 e4 9b 93 49 81 fe 00 00 50 00 73 2c 0f b7 03 25 ff 1f 00 00 49 39 c7 74 30 <49> ff c6 41 8b 45 00 89 c1 c1 e9 08 c1 e8 02 83 e0 3f 01 c8 48 83
RSP: 0018:ffffc90007797580 EFLAGS: 00000016
RAX: 00000000000007b5 RBX: ffffffff939f658c RCX: 000000000001c05c
RDX: ffffffff9456e4f8 RSI: 0000000000000003 RDI: 000000000004015d
RBP: ffffffff949ae970 R08: ffffffff81b0c988 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff20f48f0 R12: 000000000003e69e
R13: ffffffff94a867f0 R14: 000000000001c05e R15: 0000000000000d21
FS:  00007f8aff0146c0(0000) GS:ffff8882a8ccd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6d60955000 CR3: 000000010aa36000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lockdep_unregister_key+0x1c3/0x350
 __qdisc_destroy+0x1ab/0x470
 dev_shutdown+0x92/0x450
 unregister_netdevice_many_notify+0x11f4/0x2140
 unregister_netdevice_queue+0x2f5/0x340
 __tun_detach+0x1074/0x1900
 tun_chr_close+0x10a/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+0x10e/0x770
 do_syscall_64+0x328/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8afe19e159
Code: Unable to access opcode bytes at 0x7f8afe19e12f.
RSP: 002b:00007f8aff014028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f8afe426540 RCX: 00007f8afe19e159
RDX: 0000200000002280 RSI: 0000000000008914 RDI: 0000000000000005
RBP: 00007f8afe23506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8afe4265d8 R14: 00007f8afe426540 R15: 00007ffd88e9b378
 </TASK>
