INFO: task kworker/u8:4:5849 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4    state:D stack:21816 pid:5849  tgid:5849  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 rdma_dev_change_netns+0x39/0x300
 rdma_dev_exit_net+0x203/0x340
 ops_undo_list+0x49a/0x990
 cleanup_net+0x4d8/0x820
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task syz.3.1928:10382 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1928      state:D stack:22808 pid:10382 tgid:10374 ppid:5981   task_flags:0x400140 flags:0x00080002
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: 0033:0x7f90c358ec29
RSP: 002b:00007f90c17f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f90c37d6090 RCX: 00007f90c358ec29
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 000000000000000a
RBP: 00007f90c3611e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f90c37d6128 R14: 00007f90c37d6090 R15: 00007ffe4bd6dcf8
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_trace/32:
 #0: ffffffff8dd3b690 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{4:4}, at: rcu_tasks_one_gp+0xaf9/0xdf0
1 lock held by khungtaskd/35:
 #0: ffffffff8dd3a960 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5645:
 #0: ffff88810528b0a0 (&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/u8:4/5849:
 #0: ffff88801aef7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000419fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f0c21f0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820
 #3: ffff88811da40700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
2 locks held by syz.3.1928/10382:
 #0: ffffffff9990c4f8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x302/0x980
 #1: ffff88811da40700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0
14 locks held by syz.5.4261/15855:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 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: 15855 Comm: syz.5.4261 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:validate_chain+0x2cc/0x2140
Code: 00 0f 84 a2 17 00 00 b8 01 00 00 00 65 48 8b 0d da 77 ae 10 48 3b 8c 24 d8 00 00 00 0f 85 43 1c 00 00 48 81 c4 e0 00 00 00 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 41 83 fe 03 ba 02 00
RSP: 0018:ffffc900001deb30 EFLAGS: 00000086
RAX: 0000000000000001 RBX: 0000000000000009 RCX: ba2d5da9638dd000
RDX: 0000000000000000 RSI: ffff88801f5c4698 RDI: ffff88801f5c3a00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff818aef48
R10: dffffc0000000000 R11: ffffffff81ee8d90 R12: 00000000c6ada59f
R13: ffff88801f5c4530 R14: ffff88801f5c4698 R15: 03813abc02fcf7df
FS:  00007f80ec2b36c0(0000) GS:ffff8881a4173000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005639a00a6440 CR3: 00000000421f8000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __lock_acquire+0xab9/0xd20
 lock_acquire+0x120/0x360
 __task_pid_nr_ns+0x48/0x490
 __perf_event_header__init_id+0x1d2/0x480
 perf_prepare_sample+0x135/0x2450
 perf_event_output_forward+0x151/0x430
 __perf_event_overflow+0x830/0xe40
 perf_swevent_event+0x2f4/0x5e0
 perf_tp_event+0x4f6/0x1380
 perf_trace_run_bpf_submit+0xee/0x170
 perf_trace_lock+0x2f8/0x3b0
 lock_release+0x3b2/0x3e0
 unwind_next_frame+0x19a9/0x2390
 perf_callchain_kernel+0x469/0x5c0
 get_perf_callchain+0x23c/0x6f0
 perf_prepare_sample+0x4c6/0x2450
 perf_event_output_forward+0x151/0x430
 __perf_event_overflow+0x830/0xe40
 perf_swevent_hrtimer+0x3b8/0x500
 __hrtimer_run_queues+0x4e0/0xc60
 hrtimer_interrupt+0x45b/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x410
 sysvec_apic_timer_interrupt+0x52/0xc0
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:__perf_event_overflow+0x0/0xe40
Code: ff 4c 89 ff be 01 00 00 00 4c 89 f2 48 89 d9 5b 41 5e 41 5f eb 14 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48
RSP: 0018:ffffc900001e01d8 EFLAGS: 00000246
RAX: ffffffff81ef448c RBX: 1ffff9200003c044 RCX: ffff888136632a68
RDX: ffffc900001e0340 RSI: 0000000000000000 RDI: ffff88803be1e400
RBP: ffffc900001e02b0 R08: ffffc900001e0357 R09: 0000000000000000
R10: ffffc900001e0348 R11: fffff5200003c06b R12: 0000000000000001
R13: dffffc0000000000 R14: ffff888136632a68 R15: ffff88803be1e400
 perf_swevent_event+0x2f4/0x5e0
 perf_tp_event+0x4f6/0x1380
 perf_trace_run_bpf_submit+0xee/0x170
 perf_trace_lock+0x2f8/0x3b0
 lock_release+0x3b2/0x3e0
 unwind_next_frame+0x19a9/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 slab_free_after_rcu_debug+0x129/0x2a0
 rcu_core+0xcab/0x1770
 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:unmap_page_range+0x1d6a/0x4370
Code: 75 03 00 00 e8 c7 21 b5 ff 48 8b 7c 24 58 e8 bd 18 f1 ff eb 05 e8 b6 21 b5 ff 48 b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 <74> 08 4c 89 e7 e8 ac cb 19 00 49 8b 1c 24 48 89 de 48 83 e6 01 31
RSP: 0018:ffffc90002f3f380 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0400000000000040 RCX: 0000000000080000
RDX: ffffc90026cc6000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90002f3f630 R08: ffffc90002f3eb17 R09: 0000000000000000
R10: ffffc90002f3eb00 R11: fffff520005e7d63 R12: ffffea0000ff5398
R13: 1ffffd40001fea73 R14: 800000003fd4e000 R15: 800000003fd4e007
 unmap_vmas+0x399/0x580
 exit_mmap+0x248/0xb50
 __mmput+0x118/0x430
 copy_mm+0x1f3/0x4b0
 copy_process+0x1706/0x3c00
 kernel_clone+0x21e/0x840
 __x64_sys_clone+0x18b/0x1e0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f80eb38ec29
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:00007f80ec2b2fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f80eb5d5fa0 RCX: 00007f80eb38ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f80eb411e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f80eb5d6038 R14: 00007f80eb5d5fa0 R15: 00007ffcb1b2d748
 </TASK>
