INFO: task syz.2.7482:22989 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.7482      state:D stack:22920 pid:22989 tgid:22987 ppid:5859   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x9a/0x270
 wait_for_completion+0x2bf/0x5d0
 disable_device+0x1c6/0x320
 __ib_unregister_device+0x2cb/0x3f0
 ib_unregister_device_and_put+0xb8/0xf0
 nldev_dellink+0x2d1/0x320
 rdma_nl_rcv+0x6ae/0x980
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdb7878ebe9
RSP: 002b:00007fdb769ee038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fdb789c5fa0 RCX: 00007fdb7878ebe9
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000003
RBP: 00007fdb78811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdb789c6038 R14: 00007fdb789c5fa0 R15: 00007ffc31699868
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5679:
 #0: ffff888022f9a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
4 locks held by kworker/u8:4/5885:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000345fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52bdb0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffff88810825c700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
2 locks held by syz.2.7482/22989:
 #0: ffffffff99e6a8f8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x302/0x980
 #1: ffff88810825c700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0
2 locks held by syz.0.11668/32380:
 #0: ffffffff8f538c48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
 #1: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730

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

NMI backtrace for cpu 1
CPU: 1 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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32338 Comm: syz.3.11651 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:__skb_try_recv_datagram+0x15/0x4e0
Code: 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 81 ec a0 00 00 00 <4d> 89 ce 4c 89 04 24 48 89 8c 24 88 00 00 00 89 54 24 0c 48 89 74
RSP: 0018:ffffc90002a0f600 EFLAGS: 00000286
RAX: 1ffff92000541f00 RBX: ffffc90002a0f800 RCX: ffffc90002a0f6ec
RDX: 0000000000002162 RSI: ffff8881288f00e8 RDI: ffff8881288f0000
RBP: 0000000000000040 R08: ffffc90002a0f800 R09: ffffc90002a0f6f8
R10: ffffc90002a0f7c0 R11: fffff52000541efc R12: ffff8881288f00e8
R13: dffffc0000000000 R14: ffff8881288f0000 R15: dffffc0000000000
FS:  00007f12c813b6c0(0000) GS:ffff8880b8618000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000d20030 CR3: 000000010ab46000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 skb_recv_datagram+0xbe/0x190
 hci_sock_recvmsg+0x1d5/0x8f0
 sock_recvmsg_nosec+0x186/0x1c0
 ____sys_recvmsg+0x3aa/0x460
 ___sys_recvmsg+0x1b5/0x510
 do_recvmmsg+0x307/0x770
 __x64_sys_recvmmsg+0x190/0x240
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f12c738ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f12c813b038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f12c75c5fa0 RCX: 00007f12c738ebe9
RDX: 00000000040001af RSI: 0000200000000a40 RDI: 000000000000000a
RBP: 00007f12c7411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000012122 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f12c75c6038 R14: 00007f12c75c5fa0 R15: 00007ffff1c8edf8
 </TASK>
