======================================
| [   13.433568][    C3] 1 lock held by swapper/3/0:
| [ 13.433776][ C3] #0: ffffffff98b774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   13.434145][    C3]
| [   13.434145][    C3] stack backtrace:
[   13.434401][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.434403][    C3] Call Trace:
[   13.434405][    C3]  <IRQ>
[ 13.434407][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.434413][ C3] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 13.434418][ C3] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 13.434423][ C3] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 13.434427][ C3] ? save_trace (kernel/locking/lockdep.c:595) 
[ 13.434431][ C3] mark_lock (kernel/locking/lockdep.c:4756) 
[ 13.434435][ C3] mark_usage (kernel/locking/lockdep.c:4645) 
[ 13.434439][ C3] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 13.434442][ C3] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 13.434447][ C3] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 13.434450][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.434453][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 13.434458][ C3] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 13.434461][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.434465][ C3] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 13.434468][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.434470][ C3] simple_pin_fs (fs/libfs.c:1067) 
[ 13.434473][ C3] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 13.434477][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 13.434481][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 13.434484][ C3] ? __sk_destruct (./include/linux/instrumented.h:96 ./include/linux/atomic/atomic-instrumented.h:400 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/net_namespace.h:287 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.434490][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.434493][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 13.434496][ C3] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 13.434499][ C3] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 13.434504][ C3] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.434507][ C3] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.434510][ C3] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.434512][ C3] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.434515][ C3] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.434519][ C3] ? do_idle (kernel/sched/idle.c:325) 
[ 13.434522][ C3] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.434525][ C3] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.434529][ C3] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 13.434536][ C3] __put_net (net/core/net_namespace.c:732) 
[ 13.434541][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.434545][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.434548][ C3] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.434551][ C3] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 13.434555][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 13.434558][ C3] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.434562][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 13.434566][ C3] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.434570][ C3] rcu_core (kernel/rcu/tree.c:2834) 
[ 13.434575][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 13.434581][ C3] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 13.434584][ C3] irq_exit_rcu (kernel/softirq.c:698) 
[ 13.434587][ C3] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   13.434591][    C3]  </IRQ>
[   13.434592][    C3]  <TASK>
[ 13.434594][ C3] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.434596][ C3] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.434601][ C3] Code: 92 b4 00 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 83 07 0f 00 fb f4 <e9> fc 54 02 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
All code
========
   0:	92                   	xchg   %eax,%edx
   1:	b4 00                	mov    $0x0,%ah
   3:	c3                   	ret
   4:	cc                   	int3
   5:	cc                   	int3
   6:	cc                   	int3
   7:	cc                   	int3
   8:	0f 1f 00             	nopl   (%rax)
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d 83 07 0f 00 	verw   0xf0783(%rip)        # 0xf07ab
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	e9 fc 54 02 00       	jmp    0x2552b		<-- trapping instruction
  2f:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  36:	00 00 00 
  39:	66 90                	xchg   %ax,%ax
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	e9 fc 54 02 00       	jmp    0x25501
   5:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
   c:	00 00 00 
   f:	66 90                	xchg   %ax,%ax
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[   13.434604][    C3] RSP: 0018:ffffc90000157de8 EFLAGS: 00000246
[   13.434607][    C3] RAX: 0000000000037081 RBX: 1ffff9200002afc1 RCX: ffffffff97ba35d9
[   13.434609][    C3] RDX: 0000000000000000 RSI: ffffffff9869175c RDI: ffffffff97e53ca0
[   13.434611][    C3] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1005eb66fa
[   13.434612][    C3] R10: ffff88802f5b37d3 R11: ffffffff98811288 R12: 0000000000000000
[   13.434614][    C3] R13: ffff888001bf45c0 R14: dffffc0000000000 R15: 0000000000000000
[ 13.434618][ C3] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 13.434623][ C3] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.434625][ C3] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.434628][ C3] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.434631][ C3] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 13.434635][ C3] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 13.434640][ C3] do_idle (kernel/sched/idle.c:325) 
[ 13.434644][ C3] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.434647][ C3] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.434650][ C3] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 13.434655][ C3] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   13.451720][    C3] RCU nest depth: 0, expected: 0
| [   13.452018][    C3] INFO: lockdep is turned off.
| [   13.452218][    C3] Preemption disabled at:
| [ 13.452220][ C3] 0x0 
[   13.452558][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.452560][    C3] Call Trace:
[   13.452561][    C3]  <IRQ>
[ 13.452563][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.452571][ C3] __might_resched (kernel/sched/core.c:8796) 
[ 13.452578][ C3] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 13.452582][ C3] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 13.452585][ C3] ? simple_recursive_removal (fs/libfs.c:614) 
[ 13.452589][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 13.452594][ C3] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141) 
[ 13.452598][ C3] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 13.452601][ C3] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141) 
[ 13.452604][ C3] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 13.452610][ C3] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 13.452613][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 13.452617][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 13.452620][ C3] ? __sk_destruct (./include/linux/instrumented.h:96 ./include/linux/atomic/atomic-instrumented.h:400 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/net_namespace.h:287 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.452625][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.452629][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 13.452631][ C3] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 13.452636][ C3] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 13.452640][ C3] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.452644][ C3] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.452647][ C3] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.452649][ C3] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.452652][ C3] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.452655][ C3] ? do_idle (kernel/sched/idle.c:325) 
[ 13.452658][ C3] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.452660][ C3] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.452663][ C3] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 13.452670][ C3] __put_net (net/core/net_namespace.c:732) 
[ 13.452673][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.452678][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.452681][ C3] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.452684][ C3] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 13.452688][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 13.452692][ C3] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.452696][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 13.452700][ C3] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.452705][ C3] rcu_core (kernel/rcu/tree.c:2834) 
[ 13.452710][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 13.452715][ C3] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 13.452718][ C3] irq_exit_rcu (kernel/softirq.c:698) 
[ 13.452721][ C3] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   13.452725][    C3]  </IRQ>
[   13.452726][    C3]  <TASK>
[ 13.452727][ C3] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.452730][ C3] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.452734][ C3] Code: 92 b4 00 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 83 07 0f 00 fb f4 <e9> fc 54 02 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
All code
========
   0:	92                   	xchg   %eax,%edx
   1:	b4 00                	mov    $0x0,%ah
   3:	c3                   	ret
   4:	cc                   	int3
   5:	cc                   	int3
   6:	cc                   	int3
   7:	cc                   	int3
   8:	0f 1f 00             	nopl   (%rax)
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d 83 07 0f 00 	verw   0xf0783(%rip)        # 0xf07ab
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	e9 fc 54 02 00       	jmp    0x2552b		<-- trapping instruction
  2f:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  36:	00 00 00 
  39:	66 90                	xchg   %ax,%ax
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	e9 fc 54 02 00       	jmp    0x25501
   5:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
   c:	00 00 00 
   f:	66 90                	xchg   %ax,%ax
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[   13.452737][    C3] RSP: 0018:ffffc90000157de8 EFLAGS: 00000246
[   13.452740][    C3] RAX: 0000000000037081 RBX: 1ffff9200002afc1 RCX: ffffffff97ba35d9
[   13.452742][    C3] RDX: 0000000000000000 RSI: ffffffff9869175c RDI: ffffffff97e53ca0
[   13.452743][    C3] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1005eb66fa
[   13.452745][    C3] R10: ffff88802f5b37d3 R11: ffffffff98811288 R12: 0000000000000000
[   13.452747][    C3] R13: ffff888001bf45c0 R14: dffffc0000000000 R15: 0000000000000000
[ 13.452750][ C3] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 13.452755][ C3] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.452757][ C3] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.452760][ C3] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.452763][ C3] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 13.452767][ C3] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 13.452772][ C3] do_idle (kernel/sched/idle.c:325) 
[ 13.452776][ C3] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.452779][ C3] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.452782][ C3] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 


Finger prints:
__might_resched:down_write:simple_recursive_removal:debugfs_remove:ref_tracker_dir_exit
mark_lock_irq:mark_lock:mark_usage:__lock_acquire:_raw_spin_lock