======================================
| [   15.245216][    C1] 1 lock held by swapper/1/0:
| [ 15.245559][ C1] #0: ffffffffaad749c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2562) 
| [   15.246185][    C1]
| [   15.246185][    C1] stack backtrace:
[   15.246619][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   15.246624][    C1] Call Trace:
[   15.246627][    C1]  <IRQ>
[ 15.246632][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 15.246644][ C1] print_usage_bug.part.0 (kernel/locking/lockdep.c:4046) 
[ 15.246655][ C1] mark_lock_irq (kernel/locking/lockdep.c:4011 kernel/locking/lockdep.c:4057 kernel/locking/lockdep.c:4268) 
[ 15.246663][ C1] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 15.246671][ C1] ? save_trace (kernel/locking/lockdep.c:594) 
[ 15.246680][ C1] mark_lock (kernel/locking/lockdep.c:4754) 
[ 15.246686][ C1] mark_usage (kernel/locking/lockdep.c:4643) 
[ 15.246691][ C1] __lock_acquire (kernel/locking/lockdep.c:5189) 
[ 15.246699][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:472 kernel/locking/lockdep.c:5868) 
[ 15.246705][ C1] ? simple_pin_fs (fs/libfs.c:1066) 
[ 15.246714][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 15.246721][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5829) 
[ 15.246725][ C1] ? simple_pin_fs (fs/libfs.c:1066) 
[ 15.246733][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 15.246740][ C1] ? simple_pin_fs (fs/libfs.c:1066) 
[ 15.246744][ C1] simple_pin_fs (fs/libfs.c:1066) 
[ 15.246750][ C1] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 15.246758][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 15.246769][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 15.246775][ C1] ? __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:2366) 
[ 15.246783][ C1] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 15.246791][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 15.246796][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 15.246802][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[ 15.246808][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 15.246815][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:81) 
[ 15.246820][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:748) 
[ 15.246824][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 15.246829][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 15.246835][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 15.246838][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 15.246842][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 15.246847][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 15.246859][ C1] __put_net (net/core/net_namespace.c:732) 
[ 15.246865][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 15.246872][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 15.246877][ C1] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 15.246884][ C1] ? find_held_lock (kernel/locking/lockdep.c:5348) 
[ 15.246892][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 15.246899][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 15.246905][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 15.246911][ C1] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 15.246920][ C1] rcu_core (kernel/rcu/tree.c:2826) 
[ 15.246927][ C1] handle_softirqs (kernel/softirq.c:579) 
[ 15.246936][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 15.246942][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 15.246947][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[   15.246953][    C1]  </IRQ>
[   15.246955][    C1]  <TASK>
[ 15.246958][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 15.246962][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:81) 
[ 15.246969][ C1] Code: 50 b7 00 e9 c3 57 02 00 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 c3 45 12 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
All code
========
   0:	50                   	push   %rax
   1:	b7 00                	mov    $0x0,%bh
   3:	e9 c3 57 02 00       	jmp    0x257cb
   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 c3 45 12 00 	verw   0x1245c3(%rip)        # 0x1245eb
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	c3                   	ret		<-- trapping instruction
  2b:	cc                   	int3
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  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:	c3                   	ret
   1:	cc                   	int3
   2:	cc                   	int3
   3:	cc                   	int3
   4:	cc                   	int3
   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
[   15.246974][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000246
[   15.246980][    C1] RAX: 0000000000067e05 RBX: 1ffff92000026fc1 RCX: ffffffffa9d6ea19
[   15.246984][    C1] RDX: 0000000000000000 RSI: ffffffffaa889a45 RDI: ffffffffaa0513a0
[   15.246987][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c1667a
[   15.246990][    C1] R10: ffff8880360b33d3 R11: 0000000000000000 R12: 0000000000000000
[   15.246993][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 15.247001][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 15.247012][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:748) 
[ 15.247016][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 15.247020][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 15.247025][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 15.247032][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 15.247041][ C1] do_idle (kernel/sched/idle.c:325) 
[ 15.247047][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 15.247052][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 15.247057][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 15.247066][ C1] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   15.275880][    C1] RCU nest depth: 0, expected: 0
| [   15.276461][    C1] INFO: lockdep is turned off.
| [   15.276790][    C1] Preemption disabled at:
| [ 15.276793][ C1] 0x0 
[   15.277382][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   15.277386][    C1] Call Trace:
[   15.277389][    C1]  <IRQ>
[ 15.277395][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 15.277409][ C1] __might_resched (kernel/sched/core.c:8819) 
[ 15.277422][ C1] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 15.277428][ C1] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 15.277435][ C1] ? simple_recursive_removal (./include/linux/dcache.h:345 fs/libfs.c:610) 
[ 15.277444][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 15.277452][ C1] ? 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) 
[ 15.277462][ C1] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:616) 
[ 15.277468][ C1] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 15.277476][ C1] ? 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) 
[ 15.277485][ C1] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 15.277490][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 15.277501][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 15.277506][ C1] ? __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:2366) 
[ 15.277514][ C1] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 15.277520][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 15.277526][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 15.277533][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[ 15.277539][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 15.277545][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:81) 
[ 15.277550][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:748) 
[ 15.277554][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 15.277558][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 15.277564][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 15.277568][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 15.277572][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 15.277578][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 15.277589][ C1] __put_net (net/core/net_namespace.c:732) 
[ 15.277596][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 15.277603][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 15.277608][ C1] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 15.277616][ C1] ? find_held_lock (kernel/locking/lockdep.c:5348) 
[ 15.277626][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 15.277633][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 15.277641][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 15.277646][ C1] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 15.277655][ C1] rcu_core (kernel/rcu/tree.c:2826) 
[ 15.277662][ C1] handle_softirqs (kernel/softirq.c:579) 
[ 15.277672][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 15.277677][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 15.277681][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[   15.277686][    C1]  </IRQ>
[   15.277687][    C1]  <TASK>
[ 15.277690][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 15.277695][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:81) 
[ 15.277701][ C1] Code: 50 b7 00 e9 c3 57 02 00 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 c3 45 12 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
All code
========
   0:	50                   	push   %rax
   1:	b7 00                	mov    $0x0,%bh
   3:	e9 c3 57 02 00       	jmp    0x257cb
   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 c3 45 12 00 	verw   0x1245c3(%rip)        # 0x1245eb
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	c3                   	ret		<-- trapping instruction
  2b:	cc                   	int3
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  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:	c3                   	ret
   1:	cc                   	int3
   2:	cc                   	int3
   3:	cc                   	int3
   4:	cc                   	int3
   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
[   15.277706][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000246
[   15.277713][    C1] RAX: 0000000000067e05 RBX: 1ffff92000026fc1 RCX: ffffffffa9d6ea19
[   15.277716][    C1] RDX: 0000000000000000 RSI: ffffffffaa889a45 RDI: ffffffffaa0513a0
[   15.277720][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c1667a
[   15.277723][    C1] R10: ffff8880360b33d3 R11: 0000000000000000 R12: 0000000000000000
[   15.277726][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 15.277734][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 15.277744][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:748) 
[ 15.277748][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 15.277752][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 15.277758][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 15.277765][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 15.277773][ C1] do_idle (kernel/sched/idle.c:325) 
[ 15.277779][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 15.277784][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 15.277790][ C1] ? __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