======================================
| [   13.808238][    C3] 1 lock held by swapper/3/0:
| [ 13.808440][ C3] #0: ffffffff8e1774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   13.808805][    C3]
| [   13.808805][    C3] stack backtrace:
[   13.809074][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.809077][    C3] Call Trace:
[   13.809079][    C3]  <IRQ>
[ 13.809082][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.809089][ C3] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 13.809094][ C3] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 13.809099][ C3] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 13.809104][ C3] ? save_trace (kernel/locking/lockdep.c:595) 
[ 13.809109][ C3] mark_lock (kernel/locking/lockdep.c:4756) 
[ 13.809113][ C3] mark_usage (kernel/locking/lockdep.c:4645) 
[ 13.809116][ C3] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 13.809120][ C3] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 13.809124][ C3] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 13.809128][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.809131][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 13.809137][ C3] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 13.809140][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.809144][ C3] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 13.809147][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.809150][ C3] simple_pin_fs (fs/libfs.c:1067) 
[ 13.809153][ C3] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 13.809156][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 13.809162][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 13.809165][ 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) 
[ 13.809172][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.809175][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 13.809178][ C3] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 13.809181][ C3] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 13.809187][ C3] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.809191][ C3] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.809195][ C3] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.809197][ C3] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.809199][ C3] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.809204][ C3] ? do_idle (kernel/sched/idle.c:325) 
[ 13.809207][ C3] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.809210][ C3] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.809215][ C3] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 13.809223][ C3] __put_net (net/core/net_namespace.c:732) 
[ 13.809227][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.809232][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.809234][ C3] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.809238][ C3] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 13.809242][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 13.809246][ C3] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.809249][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 13.809253][ C3] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.809258][ C3] rcu_core (kernel/rcu/tree.c:2834) 
[ 13.809263][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 13.809269][ C3] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 13.809272][ C3] irq_exit_rcu (kernel/softirq.c:698) 
[ 13.809275][ C3] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   13.809279][    C3]  </IRQ>
[   13.809280][    C3]  <TASK>
[ 13.809282][ C3] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.809285][ C3] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.809289][ 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
[   13.809292][    C3] RSP: 0018:ffffc90000157de8 EFLAGS: 00000246
[   13.809296][    C3] RAX: 0000000000035f21 RBX: 1ffff9200002afc1 RCX: ffffffff8d1a25d9
[   13.809298][    C3] RDX: 0000000000000000 RSI: ffffffff8dc9175c RDI: ffffffff8d453ca0
[   13.809300][    C3] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c366fa
[   13.809302][    C3] R10: ffff8880361b37d3 R11: ffffffff8de11288 R12: 0000000000000000
[   13.809303][    C3] R13: ffff888001bf45c0 R14: dffffc0000000000 R15: 0000000000000000
[ 13.809307][ C3] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 13.809312][ C3] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.809315][ C3] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.809317][ C3] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.809321][ C3] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 13.809325][ C3] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 13.809330][ C3] do_idle (kernel/sched/idle.c:325) 
[ 13.809334][ C3] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.809337][ C3] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.809340][ C3] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 13.809345][ C3] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   13.826454][    C3] RCU nest depth: 0, expected: 0
| [   13.826645][    C3] INFO: lockdep is turned off.
| [   13.826842][    C3] Preemption disabled at:
| [ 13.826844][ C3] 0x0 
[   13.827192][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.827194][    C3] Call Trace:
[   13.827197][    C3]  <IRQ>
[ 13.827199][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.827208][ C3] __might_resched (kernel/sched/core.c:8796) 
[ 13.827217][ C3] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 13.827222][ C3] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 13.827224][ C3] ? simple_recursive_removal (fs/libfs.c:614) 
[ 13.827230][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 13.827237][ 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) 
[ 13.827241][ C3] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 13.827244][ 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) 
[ 13.827247][ C3] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 13.827253][ C3] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 13.827256][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 13.827261][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 13.827264][ 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) 
[ 13.827270][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.827274][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 13.827277][ C3] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 13.827283][ C3] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 13.827288][ C3] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.827292][ C3] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.827296][ C3] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.827299][ C3] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.827301][ C3] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.827306][ C3] ? do_idle (kernel/sched/idle.c:325) 
[ 13.827309][ C3] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.827311][ C3] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.827315][ C3] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 13.827323][ C3] __put_net (net/core/net_namespace.c:732) 
[ 13.827327][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.827331][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.827334][ C3] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.827337][ C3] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 13.827342][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 13.827345][ C3] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.827350][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 13.827354][ C3] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.827358][ C3] rcu_core (kernel/rcu/tree.c:2834) 
[ 13.827364][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 13.827369][ C3] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 13.827373][ C3] irq_exit_rcu (kernel/softirq.c:698) 
[ 13.827376][ C3] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   13.827379][    C3]  </IRQ>
[   13.827381][    C3]  <TASK>
[ 13.827382][ C3] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.827385][ C3] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.827389][ 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
[   13.827392][    C3] RSP: 0018:ffffc90000157de8 EFLAGS: 00000246
[   13.827395][    C3] RAX: 0000000000035f21 RBX: 1ffff9200002afc1 RCX: ffffffff8d1a25d9
[   13.827397][    C3] RDX: 0000000000000000 RSI: ffffffff8dc9175c RDI: ffffffff8d453ca0
[   13.827399][    C3] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c366fa
[   13.827400][    C3] R10: ffff8880361b37d3 R11: ffffffff8de11288 R12: 0000000000000000
[   13.827402][    C3] R13: ffff888001bf45c0 R14: dffffc0000000000 R15: 0000000000000000
[ 13.827406][ C3] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 13.827410][ C3] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.827413][ C3] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.827416][ C3] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.827419][ C3] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 13.827423][ C3] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 13.827428][ C3] do_idle (kernel/sched/idle.c:325) 
[ 13.827431][ C3] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.827435][ C3] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.827438][ 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