INFO: task syz.2.7957:26089 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.7957      state:D stack:22696 pid:26089 tgid:26087 ppid:5842   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: 0033:0x7fed9d78eba9
RSP: 002b:00007fed9b9f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fed9d9d5fa0 RCX: 00007fed9d78eba9
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000006
RBP: 00007fed9d811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fed9d9d6038 R14: 00007fed9d9d5fa0 R15: 00007ffe396c3748
 </TASK>

Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
 #0: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
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/5674:
 #0: ffff8880292900a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
4 locks held by kworker/u8:2/5738:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90002fdfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52d430 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffff88811c0a8700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
1 lock held by sshd/5814:
1 lock held by syz-executor/5846:
 #0: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
2 locks held by syz.2.7957/26089:
 #0: ffffffff99e6f8f8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x302/0x980
 #1: ffff88811c0a8700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0
2 locks held by syz.4.9000/31038:
 #0: ffffffff8f52d430 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0
 #1: ffff88811c0a8700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300

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

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: 28419 Comm: ipvs-e:101:0 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:__sanitizer_cov_trace_switch+0x82/0x130
Code: 00 00 b9 01 00 00 00 48 85 c0 0f 84 b4 00 00 00 41 57 41 56 41 54 53 48 8b 54 24 20 65 4c 8b 04 25 08 d0 a0 92 45 31 c9 eb 08 <49> ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 19 0b e1 10 41
RSP: 0018:ffffc9000468eda0 EFLAGS: 00000093
RAX: 0000000000000020 RBX: 0000000000000004 RCX: 0000000000000005
RDX: ffffffff81c19a55 RSI: ffffffff8e18ef80 RDI: 0000000000000004
RBP: 000000827c4bf8ca R08: ffff88810d8e8000 R09: 000000000000000e
R10: 000000000000000e R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888100036010 R14: ffff8881000362cc R15: 000000000001bee4
FS:  0000000000000000(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055bbae6615c8 CR3: 000000000df36000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 rb_event_length+0x45/0x400
 rb_read_data_buffer+0x438/0x580
 check_buffer+0x28a/0x750
 __rb_reserve_next+0x592/0xdb0
 ring_buffer_lock_reserve+0xbb5/0x1010
 trace_event_buffer_lock_reserve+0x1d0/0x6f0
 trace_event_buffer_reserve+0x248/0x340
 trace_event_raw_event_bpf_trace_printk+0x100/0x260
 trace_bpf_trace_printk+0x170/0x1d0
 bpf_trace_printk+0x11e/0x190
 bpf_prog_9e1c00255e17e72e+0x39/0x3f
 bpf_trace_run1+0x27f/0x4b0
 __bpf_trace_rcu_utilization+0xa1/0xf0
 __traceiter_rcu_utilization+0x7a/0xb0
 trace_rcu_utilization+0x1ad/0x1d0
 rcu_note_context_switch+0xdc1/0x1140
 __schedule+0x35d/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 ip_vs_estimation_kthread+0x2a2a/0x3a00
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
