INFO: task kworker/u10:8:7533 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u10:8   state:D stack:17704 pid:7533  tgid:7533  ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: ib-unreg-wq ib_unregister_work
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_work+0x19/0x30
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900000f7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52d310 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_run_todo+0x79b/0xea0
2 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a120 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/0:2/792:
2 locks held by getty/5670:
 #0: ffff888021e490a0 (&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
3 locks held by kworker/u10:7/7532:
 #0: ffff88801a489948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90007657bc0 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8e13fa80 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570
3 locks held by kworker/u10:8/7533:
 #0: ffff88801bf39948 ((wq_completion)ib-unreg-wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90007497bc0 ((work_completion)(&device->unregistration_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88803600c700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0
2 locks held by syz.4.2677/15019:
 #0: ffffffff8f52d310 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0
 #1: ffff88803600c700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
2 locks held by syz.6.2713/15135:
 #0: ffffffff8f52d310 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0
 #1: ffff88803600c700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
1 lock held by syz.9.2902/15839:
 #0: ffff888033656ca8 (&ctx->mutex){+.+.}-{4:4}, at: perf_event_ctx_lock_nested+0x38f/0x460
7 locks held by syz.9.2902/15840:
1 lock held by syz.8.2905/15852:
 #0: ffffffff8e19d6c8 (event_mutex){+.+.}-{4:4}, at: perf_trace_destroy+0x2e/0x150
2 locks held by syz.8.2905/15855:
 #0: ffffffff8e19d6c8 (event_mutex){+.+.}-{4:4}, at: perf_trace_destroy+0x2e/0x150
 #1: ffffffff8e13fbb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
2 locks held by syz-executor/15860:
 #0: ffffffff8fa3e2c8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70
3 locks held by syz-executor/15863:
 #0: ffffffff8eca97e0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70
 #2: ffffffff8e13fbb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
2 locks held by syz-executor/15871:
 #0: ffffffff8f52d310 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0
 #1: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1c/0x1d0

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

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+0x439/0x7d0
 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: 15840 Comm: syz.9.2902 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:unwind_next_frame+0x7e7/0x2390
Code: 00 49 8d 5e 40 48 89 d8 48 c1 e8 03 80 3c 28 00 74 11 48 89 df e8 f9 65 b0 00 48 8b 34 24 48 8b 54 24 08 4c 8b 23 48 8d 5a 01 <48> 89 d0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 58 17 00 00 48 89 d8
RSP: 0018:ffffc90000007518 EFLAGS: 00000246
RAX: 1ffff92000000ec5 RBX: ffffffff903764b5 RCX: ffffffff8fba1740
RDX: ffffffff903764b4 RSI: ffffffff903764b8 RDI: ffffffff8be33da0
RBP: dffffc0000000000 R08: 0000000000000003 R09: ffffffff8172d195
R10: ffffc90000007638 R11: ffffffff81ac4d00 R12: ffffc90001cdf810
R13: ffffc90000007638 R14: ffffc900000075e8 R15: ffffc90000007620
FS:  00007f403f2d56c0(0000) GS:ffff8880b8613000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcf8fdaff8 CR3: 0000000021244000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0
 __alloc_skb+0x112/0x2d0
 ndisc_alloc_skb+0x9f/0x480
 ndisc_send_rs+0x2b5/0x630
 addrconf_rs_timer+0x369/0x670
 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:unwind_next_frame+0x223/0x2390
Code: 86 65 18 00 00 44 89 f8 4c 8d 2c 85 a4 4e e0 90 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 48 89 eb 0f 85 1c 1c 00 00 45 8b 6d 00 <44> 89 f8 ff c0 48 8d 2c 85 a4 4e e0 90 48 89 e8 48 c1 e8 03 0f b6
RSP: 0018:ffffc90001cded58 EFLAGS: 00000246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 95c80a98d0616300
RDX: 00000000000a7e25 RSI: ffffffff8be33de0 RDI: ffffffff8be33da0
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff8172d195
R10: ffffc90001cdee78 R11: ffffffff81ac4d00 R12: ffffffff81a73081
R13: 0000000000021d92 R14: ffffc90001cdee28 R15: 000000000000a730
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_stack+0x3e/0x60
 kasan_record_aux_stack+0xbd/0xd0
 call_rcu+0x157/0x9c0
 __schedule+0x17a0/0x4cc0
 preempt_schedule_common+0x83/0xd0
 preempt_schedule+0xae/0xc0
 preempt_schedule_thunk+0x16/0x30
 _raw_spin_unlock_irqrestore+0xfd/0x110
 rcu_preempt_deferred_qs_irqrestore+0x8bd/0xce0
 rcu_read_unlock_special+0x3a2/0x4b0
 __rcu_read_unlock+0x84/0xe0
 __free_frozen_pages+0xbd7/0xd30
 __put_partials+0x156/0x1a0
 put_cpu_partial+0x17c/0x250
 __slab_free+0x2d5/0x3c0
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 alloc_empty_file+0x55/0x1d0
 alloc_file_pseudo+0x13d/0x210
 anon_inode_getfile+0xc5/0x1a0
 __se_sys_perf_event_open+0xf20/0x1d70
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f403e38eba9
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:00007f403f2d5038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f403e5d5fa0 RCX: 00007f403e38eba9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 00002000000004c0
RBP: 00007f403e411e19 R08: 0000000000000001 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f403e5d6038 R14: 00007f403e5d5fa0 R15: 00007ffe593fce18
 </TASK>
