======================================
| [   15.144837][    C1] 1 lock held by swapper/1/0:
| [ 15.145085][ C1] #0: ffffffff915774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   15.145677][    C1]
| [   15.145677][    C1] stack backtrace:
[   15.146062][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   15.146066][    C1] Call Trace:
[   15.146069][    C1]  <IRQ>
[ 15.146073][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 15.146085][ C1] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 15.146097][ C1] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 15.146106][ C1] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 15.146115][ C1] ? save_trace (kernel/locking/lockdep.c:595) 
[ 15.146122][ C1] mark_lock (kernel/locking/lockdep.c:4756) 
[ 15.146129][ C1] mark_usage (kernel/locking/lockdep.c:4645) 
[ 15.146135][ C1] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 15.146141][ C1] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 15.146149][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 15.146155][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 15.146164][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 15.146171][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 15.146174][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 15.146178][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 15.146184][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 15.146188][ C1] simple_pin_fs (fs/libfs.c:1067) 
[ 15.146194][ C1] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 15.146201][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 15.146210][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 15.146214][ 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) 
[ 15.146223][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 15.146229][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 15.146233][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 15.146240][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 15.146248][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 15.146255][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 15.146260][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 15.146264][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 15.146269][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 15.146276][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 15.146281][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 15.146286][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 15.146292][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 15.146305][ C1] __put_net (net/core/net_namespace.c:732) 
[ 15.146313][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 15.146320][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 15.146325][ C1] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 15.146335][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 15.146340][ C1] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 15.146346][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 15.146350][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 15.146359][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 15.146366][ C1] handle_softirqs (kernel/softirq.c:579) 
[ 15.146376][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 15.146381][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 15.146385][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   15.146392][    C1]  </IRQ>
[   15.146394][    C1]  <TASK>
[ 15.146397][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 15.146402][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 15.146409][ 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
[   15.146414][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000246
[   15.146420][    C1] RAX: 00000000000637a5 RBX: 1ffff92000026fc1 RCX: ffffffff905a35d9
[   15.146423][    C1] RDX: 0000000000000000 RSI: ffffffff9109175c RDI: ffffffff90853ca0
[   15.146426][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c166fa
[   15.146429][    C1] R10: ffff8880360b37d3 R11: ffffffff91211288 R12: 0000000000000000
[   15.146432][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 15.146439][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 15.146448][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 15.146453][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 15.146458][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 15.146463][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 15.146471][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 15.146480][ C1] do_idle (kernel/sched/idle.c:325) 
[ 15.146487][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 15.146492][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 15.146498][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 15.146507][ C1] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   15.166366][    C1] RCU nest depth: 0, expected: 0
| [   15.166697][    C1] INFO: lockdep is turned off.
| [   15.166873][    C1] Preemption disabled at:
| [ 15.166875][ C1] 0x0 
[   15.167219][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   15.167221][    C1] Call Trace:
[   15.167223][    C1]  <IRQ>
[ 15.167228][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 15.167238][ C1] __might_resched (kernel/sched/core.c:8796) 
[ 15.167249][ C1] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 15.167255][ C1] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 15.167258][ C1] ? simple_recursive_removal (fs/libfs.c:614) 
[ 15.167264][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 15.167272][ 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) 
[ 15.167277][ C1] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 15.167280][ 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) 
[ 15.167282][ C1] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 15.167289][ C1] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 15.167293][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 15.167300][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 15.167302][ 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) 
[ 15.167310][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 15.167315][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 15.167317][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 15.167324][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 15.167330][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 15.167335][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 15.167338][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 15.167342][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 15.167344][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 15.167350][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 15.167352][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 15.167355][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 15.167360][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 15.167369][ C1] __put_net (net/core/net_namespace.c:732) 
[ 15.167374][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 15.167378][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 15.167381][ C1] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 15.167387][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 15.167390][ C1] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 15.167396][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 15.167400][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 15.167406][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 15.167412][ C1] handle_softirqs (kernel/softirq.c:579) 
[ 15.167418][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 15.167422][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 15.167425][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   15.167428][    C1]  </IRQ>
[   15.167429][    C1]  <TASK>
[ 15.167431][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 15.167434][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 15.167439][ 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
[   15.167442][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000246
[   15.167446][    C1] RAX: 00000000000637a5 RBX: 1ffff92000026fc1 RCX: ffffffff905a35d9
[   15.167448][    C1] RDX: 0000000000000000 RSI: ffffffff9109175c RDI: ffffffff90853ca0
[   15.167450][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c166fa
[   15.167451][    C1] R10: ffff8880360b37d3 R11: ffffffff91211288 R12: 0000000000000000
[   15.167453][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 15.167460][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 15.167465][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 15.167468][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 15.167471][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 15.167474][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 15.167478][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 15.167484][ C1] do_idle (kernel/sched/idle.c:325) 
[ 15.167487][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 15.167491][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 15.167494][ 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