INFO: task syz.7.2358:12394 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.2358      state:D stack:23640 pid:12394 tgid:12393 ppid:8267   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: 0033:0x7f6037d8ec29
RSP: 002b:00007f6038b7d038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f6037fd5fa0 RCX: 00007f6037d8ec29
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000003
RBP: 00007f6037e11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6037fd6038 R14: 00007f6037fd5fa0 R15: 00007ffd0e5973e8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5672:
 #0: ffff88802508f0a0 (&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/u8:3/5878:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900043dfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52d2d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffff88803b6ec700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
2 locks held by syz.7.2358/12394:
 #0: ffffffff99e6f958 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x302/0x980
 #1: ffff88803b6ec700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0

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

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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 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: 0 Comm: swapper/1 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:try_to_wake_up+0x318/0x12b0
Code: bd 28 0a 00 00 be ff ff ff ff e8 33 89 e9 09 85 c0 0f 84 77 05 00 00 4c 8d b5 18 04 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 ee 06 00 00 41 83 3e 02 7c 26 4c 8d b5 40 04 00 00 4c
RSP: 0018:ffffc900001e0b20 EFLAGS: 00000806
RAX: 0000000000000000 RBX: 1ffff1102265dad5 RCX: a31bfbe881d07500
RDX: 0000000000000000 RSI: ffffffff8dba9963 RDI: ffffffff8be33f80
RBP: ffff8881132ed640 R08: ffffffff8fa3a737 R09: 1ffffffff1f474e6
R10: dffffc0000000000 R11: fffffbfff1f474e7 R12: dffffc0000000000
R13: 1ffff1102265dacb R14: ffff8881132eda58 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe87927e68 CR3: 000000010a9f4000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x61a/0x860
 run_timer_softirq+0xb7/0x180
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:finish_task_switch+0x26b/0x950
Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 df d6 eb 09 e8 1a 40 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc90000177b58 EFLAGS: 00000282
RAX: a31bfbe881d07500 RBX: 0000000000000000 RCX: a31bfbe881d07500
RDX: 0000000000000000 RSI: ffffffff8d9ba2fc RDI: ffffffff8be33f80
RBP: ffffc90000177bb0 R08: ffffffff8fa3a737 R09: 1ffffffff1f474e6
R10: dffffc0000000000 R11: fffffbfff1f474e7 R12: ffff8881000f8000
R13: dffffc0000000000 R14: ffff88802111b980 R15: ffff88813663ab58
 __schedule+0x17a0/0x4cc0
 schedule_idle+0x52/0x90
 do_idle+0x4ad/0x510
 cpu_startup_entry+0x44/0x60
 start_secondary+0x101/0x110
 common_startup_64+0x13e/0x147
 </TASK>
