INFO: task syz.2.2223:13746 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.2223      state:D stack:21368 pid:13746 tgid:13745 ppid:5854   task_flags:0x400140 flags:0x00004006
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: 0033:0x7f5b8418ebe9
RSP: 002b:00007f5b84f37038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f5b843b5fa0 RCX: 00007f5b8418ebe9
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000008
RBP: 00007f5b84211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5b843b6038 R14: 00007f5b843b5fa0 R15: 00007fff5d4cb7c8
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u8:1/13:
 #0: ffff888136639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
 #1: ffff888136624008 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
2 locks held by rcu_tasks_trace/32:
 #0: ffffffff8e13abd0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{4:4}, at: rcu_tasks_one_gp+0xaf9/0xdf0
 #1: ffffffff8e13f938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5674:
 #0: ffff888105ff60a0 (&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/u8:4/5896:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90003ccfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52af70 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffff88803c3d0700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
3 locks held by kworker/0:6/5909:
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90003cefbc0 (xfrm_state_gc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8e13f938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
2 locks held by syz.2.2223/13746:
 #0: ffffffff99e66858 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x302/0x980
 #1: ffff88803c3d0700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0
2 locks held by syz.1.3023/16596:
 #0: ffffffff8f52af70 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0
 #1: ffff88803c3d0700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
1 lock held by syz.5.3388/17924:
 #0: ffffffff8e19d448 (event_mutex){+.+.}-{4:4}, at: perf_trace_destroy+0x2e/0x150
5 locks held by syz.7.3390/17932:
1 lock held by syz.6.3392/17937:

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

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: 17932 Comm: syz.7.3390 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:asm_sysvec_apic_timer_interrupt+0x0/0x20
Code: 56 1c 79 0a e9 61 06 00 00 90 f3 0f 1e fa 0f 1f 00 fc 6a ff e8 11 05 00 00 48 89 c4 48 89 e7 e8 66 1b 79 0a e9 41 06 00 00 90 <f3> 0f 1e fa 0f 1f 00 fc 6a ff e8 f1 04 00 00 48 89 c4 48 89 e7 e8
RSP: 0018:ffffc9000427f0e8 EFLAGS: 00000086
RAX: 3fc87fc920cad000 RBX: ffffffff825d3cac RCX: 0000000000000002
RDX: ffff888107d1d640 RSI: ffffffff8be332e0 RDI: ffffffff8be332a0
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff825d3cac
R10: dffffc0000000000 R11: ffffed100892065b R12: ffff88801b6f0118
R13: dffffc0000000000 R14: ffff8880449032d0 R15: dffffc0000000000
FS:  00007faf518746c0(0000) GS:ffff8880b861c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9b0cc4ffc8 CR3: 0000000109a36000 CR4: 00000000000006f0
DR0: ffffffffffffffff DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
RIP: 0010:check_preemption_disabled+0x12/0x120
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 be ee 26 07 <48> 89 44 24 08 65 8b 05 c6 ee 26 07 65 8b 0d bb ee 26 07 f7 c1 ff
RSP: 0018:ffffc9000427f118 EFLAGS: 00000286
 rcu_is_watching+0x15/0xb0
 kernfs_root+0x55/0x230
 kernfs_next_descendant_post+0x4e/0x1f0
 kernfs_add_one+0x3e1/0x520
 __kernfs_create_file+0x22b/0x2e0
 sysfs_add_file_mode_ns+0x238/0x300
 internal_create_group+0x66d/0x1110
 sysfs_create_groups+0x59/0x120
 ib_setup_port_attrs+0xd96/0x2070
 add_one_compat_dev+0x3d6/0x5c0
 rdma_dev_init_net+0x1dd/0x270
 ops_init+0x35c/0x5c0
 setup_net+0x10c/0x320
 copy_net_ns+0x31b/0x4d0
 create_new_namespaces+0x3f3/0x720
 copy_namespaces+0x438/0x4b0
 copy_process+0x1733/0x3c00
 kernel_clone+0x21e/0x840
 __x64_sys_clone+0x18b/0x1e0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faf5098ebe9
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:00007faf51873fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007faf50bb5fa0 RCX: 00007faf5098ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000042164000
RBP: 00007faf50a11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007faf50bb6038 R14: 00007faf50bb5fa0 R15: 00007fff21ac9f18
 </TASK>
