======================================
| [   13.302414][    C1] 1 lock held by swapper/1/0:
| [ 13.302625][ C1] #0: ffffffffb6d774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   13.302994][    C1]
| [   13.302994][    C1] stack backtrace:
[   13.303253][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.303255][    C1] Call Trace:
[   13.303258][    C1]  <IRQ>
[ 13.303260][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.303266][ C1] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 13.303271][ C1] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 13.303276][ C1] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 13.303280][ C1] ? save_trace (kernel/locking/lockdep.c:595) 
[ 13.303284][ C1] mark_lock (kernel/locking/lockdep.c:4756) 
[ 13.303288][ C1] mark_usage (kernel/locking/lockdep.c:4645) 
[ 13.303292][ C1] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 13.303296][ C1] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 13.303300][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 13.303303][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.303306][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 13.303311][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 13.303314][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.303318][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 13.303321][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 13.303323][ C1] simple_pin_fs (fs/libfs.c:1067) 
[ 13.303326][ C1] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 13.303330][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 13.303335][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 13.303337][ 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) 
[ 13.303343][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.303346][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 13.303348][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 13.303351][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 13.303355][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.303359][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.303362][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.303365][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.303367][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.303371][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 13.303374][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.303376][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.303380][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 13.303387][ C1] __put_net (net/core/net_namespace.c:732) 
[ 13.303391][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.303395][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.303398][ C1] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.303402][ C1] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 13.303405][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 13.303409][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.303413][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 13.303416][ C1] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.303421][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 13.303426][ C1] handle_softirqs (kernel/softirq.c:579) 
[ 13.303432][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 13.303435][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 13.303438][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   13.303441][    C1]  </IRQ>
[   13.303442][    C1]  <TASK>
[ 13.303444][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.303447][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.303451][ C1] 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
[   13.303454][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000242
[   13.303457][    C1] RAX: 000000000005e80b RBX: 1ffff92000026fc1 RCX: ffffffffb5da25d9
[   13.303459][    C1] RDX: 0000000000000000 RSI: ffffffffb689175c RDI: ffffffffb6053ca0
[   13.303461][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c166fa
[   13.303463][    C1] R10: ffff8880360b37d3 R11: ffffffffb6a11288 R12: 0000000000000000
[   13.303464][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 13.303468][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 13.303473][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.303475][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.303478][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.303481][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 13.303485][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 13.303490][ C1] do_idle (kernel/sched/idle.c:325) 
[ 13.303494][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.303497][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.303500][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 13.303505][ C1] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   13.320712][    C1] RCU nest depth: 0, expected: 0
| [   13.320906][    C1] INFO: lockdep is turned off.
| [   13.321093][    C1] Preemption disabled at:
| [ 13.321095][ C1] 0x0 
[   13.321426][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   13.321428][    C1] Call Trace:
[   13.321430][    C1]  <IRQ>
[ 13.321431][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 13.321438][ C1] __might_resched (kernel/sched/core.c:8796) 
[ 13.321446][ C1] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 13.321450][ C1] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 13.321452][ C1] ? simple_recursive_removal (fs/libfs.c:614) 
[ 13.321456][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 13.321462][ 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) 
[ 13.321465][ C1] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 13.321468][ 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) 
[ 13.321471][ C1] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 13.321476][ C1] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 13.321480][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 13.321484][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 13.321486][ 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) 
[ 13.321491][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.321494][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 13.321497][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 13.321502][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 13.321506][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.321509][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.321512][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.321515][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.321517][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.321521][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 13.321524][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.321527][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.321530][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 13.321536][ C1] __put_net (net/core/net_namespace.c:732) 
[ 13.321540][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 13.321544][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.321547][ C1] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 13.321551][ C1] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 13.321555][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 13.321558][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 13.321563][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 13.321566][ C1] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 13.321571][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 13.321576][ C1] handle_softirqs (kernel/softirq.c:579) 
[ 13.321581][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 13.321585][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 13.321588][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   13.321591][    C1]  </IRQ>
[   13.321592][    C1]  <TASK>
[ 13.321594][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 13.321597][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 13.321600][ C1] 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
[   13.321603][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000242
[   13.321606][    C1] RAX: 000000000005e80b RBX: 1ffff92000026fc1 RCX: ffffffffb5da25d9
[   13.321608][    C1] RDX: 0000000000000000 RSI: ffffffffb689175c RDI: ffffffffb6053ca0
[   13.321610][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c166fa
[   13.321611][    C1] R10: ffff8880360b37d3 R11: ffffffffb6a11288 R12: 0000000000000000
[   13.321613][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 13.321617][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 13.321621][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 13.321623][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 13.321626][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 13.321629][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 13.321633][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 13.321638][ C1] do_idle (kernel/sched/idle.c:325) 
[ 13.321641][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 13.321644][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 13.321647][ 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