======================================
| [   12.609015][    C1] 1 lock held by swapper/1/0:
| [ 12.609205][ C1] #0: ffffffff939774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   12.609541][    C1]
| [   12.609541][    C1] stack backtrace:
[   12.609780][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   12.609782][    C1] Call Trace:
[   12.609783][    C1]  <IRQ>
[ 12.609786][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 12.609792][ C1] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 12.609797][ C1] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 12.609802][ C1] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 12.609807][ C1] ? save_trace (kernel/locking/lockdep.c:595) 
[ 12.609811][ C1] mark_lock (kernel/locking/lockdep.c:4756) 
[ 12.609815][ C1] mark_usage (kernel/locking/lockdep.c:4645) 
[ 12.609818][ C1] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 12.609822][ C1] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 12.609826][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 12.609830][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 12.609833][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 12.609838][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 12.609841][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 12.609845][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 12.609848][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 12.609851][ C1] simple_pin_fs (fs/libfs.c:1067) 
[ 12.609854][ C1] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 12.609858][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 12.609862][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 12.609865][ 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:2376) 
[ 12.609871][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 12.609874][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 12.609876][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 12.609880][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 12.609884][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 12.609888][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 12.609891][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 12.609893][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 12.609896][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 12.609900][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 12.609903][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 12.609906][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 12.609910][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 12.609918][ C1] __put_net (net/core/net_namespace.c:732) 
[ 12.609922][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 12.609926][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 12.609928][ C1] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 12.609933][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 12.609937][ C1] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 12.609940][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 12.609943][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 12.609948][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 12.609953][ C1] handle_softirqs (kernel/softirq.c:579) 
[ 12.609958][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 12.609962][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 12.609965][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   12.609968][    C1]  </IRQ>
[   12.609969][    C1]  <TASK>
[ 12.609971][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 12.609974][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 12.609978][ C1] 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
[   12.609981][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000242
[   12.609984][    C1] RAX: 000000000005be45 RBX: 1ffff92000026fc1 RCX: ffffffff929a35d9
[   12.609986][    C1] RDX: 0000000000000000 RSI: ffffffff9349175c RDI: ffffffff92c53ca0
[   12.609988][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1005e966fa
[   12.609989][    C1] R10: ffff88802f4b37d3 R11: ffffffff93611288 R12: 0000000000000000
[   12.609991][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 12.609995][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 12.610000][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 12.610002][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 12.610004][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 12.610008][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 12.610012][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 12.610017][ C1] do_idle (kernel/sched/idle.c:325) 
[ 12.610020][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 12.610024][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 12.610027][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 12.610032][ C1] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   12.625665][    C1] RCU nest depth: 0, expected: 0
| [   12.625842][    C1] INFO: lockdep is turned off.
| [   12.626015][    C1] Preemption disabled at:
| [ 12.626017][ C1] 0x0 
[   12.626326][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   12.626327][    C1] Call Trace:
[   12.626329][    C1]  <IRQ>
[ 12.626331][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 12.626338][ C1] __might_resched (kernel/sched/core.c:8796) 
[ 12.626347][ C1] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 12.626351][ C1] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 12.626354][ C1] ? simple_recursive_removal (fs/libfs.c:614) 
[ 12.626359][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 12.626364][ 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) 
[ 12.626368][ C1] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 12.626371][ 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) 
[ 12.626373][ C1] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 12.626379][ C1] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 12.626382][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 12.626386][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 12.626389][ 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:2376) 
[ 12.626394][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 12.626398][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 12.626400][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 12.626405][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 12.626409][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 12.626413][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 12.626416][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 12.626419][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 12.626421][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 12.626425][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 12.626428][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 12.626430][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 12.626434][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 12.626441][ C1] __put_net (net/core/net_namespace.c:732) 
[ 12.626445][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 12.626449][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 12.626452][ C1] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 12.626457][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 12.626460][ C1] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 12.626465][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 12.626468][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 12.626474][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 12.626478][ C1] handle_softirqs (kernel/softirq.c:579) 
[ 12.626484][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 12.626487][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 12.626492][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   12.626496][    C1]  </IRQ>
[   12.626497][    C1]  <TASK>
[ 12.626498][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 12.626501][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 12.626505][ C1] 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
[   12.626507][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000242
[   12.626510][    C1] RAX: 000000000005be45 RBX: 1ffff92000026fc1 RCX: ffffffff929a35d9
[   12.626512][    C1] RDX: 0000000000000000 RSI: ffffffff9349175c RDI: ffffffff92c53ca0
[   12.626514][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1005e966fa
[   12.626516][    C1] R10: ffff88802f4b37d3 R11: ffffffff93611288 R12: 0000000000000000
[   12.626517][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 12.626521][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 12.626526][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 12.626528][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 12.626531][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 12.626534][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 12.626538][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 12.626543][ C1] do_idle (kernel/sched/idle.c:325) 
[ 12.626547][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 12.626550][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 12.626553][ 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