======================================
| [   13.660037][    C3] 1 lock held by swapper/3/0:
| [ 13.660238][ C3] #0: ffffffffa2d774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   13.660587][    C3]
| [   13.660587][    C3] stack backtrace:
[   13.660837][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.660840][    C3] Call Trace:
[   13.660842][    C3]  <IRQ>
[ 13.660845][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.660852][ C3] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 13.660859][ C3] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 13.660864][ C3] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 13.660870][ C3] ? save_trace (kernel/locking/lockdep.c:595) 
[ 13.660875][ C3] mark_lock (kernel/locking/lockdep.c:4756) 
[ 13.660879][ C3] mark_usage (kernel/locking/lockdep.c:4645) 
[ 13.660882][ C3] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 13.660886][ C3] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 13.660890][ C3] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 13.660894][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.660898][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 13.660904][ C3] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 13.660907][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.660910][ C3] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 13.660914][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.660916][ C3] simple_pin_fs (fs/libfs.c:1067) 
[ 13.660920][ C3] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 13.660924][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 13.660930][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 13.660933][ 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) 
[ 13.660940][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.660943][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 13.660946][ C3] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 13.660950][ C3] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 13.660956][ C3] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.660961][ C3] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.660964][ C3] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.660967][ C3] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.660970][ C3] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.660975][ C3] ? do_idle (kernel/sched/idle.c:325) 
[ 13.660977][ C3] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.660980][ C3] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.660985][ C3] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 13.660993][ C3] __put_net (net/core/net_namespace.c:732) 
[ 13.660998][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.661002][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.661005][ C3] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.661009][ C3] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 13.661013][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 13.661017][ C3] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.661021][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 13.661024][ C3] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.661029][ C3] rcu_core (kernel/rcu/tree.c:2834) 
[ 13.661034][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 13.661040][ C3] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 13.661043][ C3] irq_exit_rcu (kernel/softirq.c:698) 
[ 13.661046][ C3] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   13.661050][    C3]  </IRQ>
[   13.661051][    C3]  <TASK>
[ 13.661052][ C3] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.661055][ C3] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.661060][ C3] Code: a2 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 17 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:	a2 b4 00 c3 cc cc cc 	movabs %al,0xfccccccccc300b4
   7:	cc 0f 
   9:	1f                   	(bad)
   a:	00 90 90 90 90 90    	add    %dl,-0x6f6f6f70(%rax)
  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 17 0f 00 	verw   0xf1783(%rip)        # 0xf17ab
  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
[   13.661063][    C3] RSP: 0018:ffffc90000157de8 EFLAGS: 00000242
[   13.661066][    C3] RAX: 000000000003cca7 RBX: 1ffff9200002afc1 RCX: ffffffffa1da25d9
[   13.661069][    C3] RDX: 0000000000000000 RSI: ffffffffa289175c RDI: ffffffffa2053ca0
[   13.661071][    C3] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1005eb66fa
[   13.661073][    C3] R10: ffff88802f5b37d3 R11: ffffffffa2a11288 R12: 0000000000000000
[   13.661075][    C3] R13: ffff888001bf45c0 R14: dffffc0000000000 R15: 0000000000000000
[ 13.661079][ C3] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 13.661084][ C3] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.661086][ C3] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.661089][ C3] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.661092][ C3] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 13.661096][ C3] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 13.661101][ C3] do_idle (kernel/sched/idle.c:325) 
[ 13.661105][ C3] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.661108][ C3] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.661112][ C3] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 13.661116][ C3] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   13.685554][    C3] RCU nest depth: 0, expected: 0
| [   13.685866][    C3] INFO: lockdep is turned off.
| [   13.686139][    C3] Preemption disabled at:
| [ 13.686141][ C3] 0x0 
[   13.686581][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.686584][    C3] Call Trace:
[   13.686587][    C3]  <IRQ>
[ 13.686590][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.686601][ C3] __might_resched (kernel/sched/core.c:8796) 
[ 13.686611][ C3] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 13.686617][ C3] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 13.686619][ C3] ? simple_recursive_removal (fs/libfs.c:614) 
[ 13.686625][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 13.686633][ 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) 
[ 13.686637][ C3] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 13.686641][ 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) 
[ 13.686643][ C3] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 13.686650][ C3] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 13.686654][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 13.686660][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 13.686662][ 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) 
[ 13.686669][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.686674][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 13.686677][ C3] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 13.686684][ C3] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 13.686689][ C3] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.686694][ C3] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.686697][ C3] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.686700][ C3] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.686703][ C3] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.686708][ C3] ? do_idle (kernel/sched/idle.c:325) 
[ 13.686711][ C3] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.686714][ C3] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.686720][ C3] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 13.686728][ C3] __put_net (net/core/net_namespace.c:732) 
[ 13.686733][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.686737][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.686740][ C3] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.686744][ C3] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 13.686748][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 13.686754][ C3] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.686759][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 13.686763][ C3] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.686768][ C3] rcu_core (kernel/rcu/tree.c:2834) 
[ 13.686773][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 13.686779][ C3] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 13.686782][ C3] irq_exit_rcu (kernel/softirq.c:698) 
[ 13.686785][ C3] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   13.686789][    C3]  </IRQ>
[   13.686790][    C3]  <TASK>
[ 13.686792][ C3] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.686795][ C3] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.686799][ C3] Code: a2 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 17 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:	a2 b4 00 c3 cc cc cc 	movabs %al,0xfccccccccc300b4
   7:	cc 0f 
   9:	1f                   	(bad)
   a:	00 90 90 90 90 90    	add    %dl,-0x6f6f6f70(%rax)
  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 17 0f 00 	verw   0xf1783(%rip)        # 0xf17ab
  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
[   13.686802][    C3] RSP: 0018:ffffc90000157de8 EFLAGS: 00000242
[   13.686806][    C3] RAX: 000000000003cca7 RBX: 1ffff9200002afc1 RCX: ffffffffa1da25d9
[   13.686808][    C3] RDX: 0000000000000000 RSI: ffffffffa289175c RDI: ffffffffa2053ca0
[   13.686810][    C3] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1005eb66fa
[   13.686812][    C3] R10: ffff88802f5b37d3 R11: ffffffffa2a11288 R12: 0000000000000000
[   13.686813][    C3] R13: ffff888001bf45c0 R14: dffffc0000000000 R15: 0000000000000000
[ 13.686817][ C3] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 13.686822][ C3] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.686825][ C3] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.686827][ C3] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.686831][ C3] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 13.686835][ C3] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 13.686840][ C3] do_idle (kernel/sched/idle.c:325) 
[ 13.686843][ C3] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.686847][ C3] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.686850][ 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