======================================
| [   49.958783][    C1] 1 lock held by swapper/1/0:
| [ 49.958976][ C1] #0: ffffffffb0f77c00 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   49.959327][    C1]
| [   49.959327][    C1] stack backtrace:
[   49.959573][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   49.959575][    C1] Call Trace:
[   49.959577][    C1]  <IRQ>
[ 49.959580][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 49.959587][ C1] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 49.959592][ C1] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 49.959597][ C1] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 49.959602][ C1] ? save_trace (kernel/locking/lockdep.c:595) 
[ 49.959607][ C1] mark_lock (kernel/locking/lockdep.c:4756) 
[ 49.959611][ C1] mark_usage (kernel/locking/lockdep.c:4645) 
[ 49.959615][ C1] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 49.959619][ C1] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 49.959623][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 49.959627][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 49.959631][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 49.959636][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 49.959639][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 49.959644][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 49.959647][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 49.959650][ C1] simple_pin_fs (fs/libfs.c:1067) 
[ 49.959654][ C1] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 49.959658][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 49.959663][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 49.959667][ 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) 
[ 49.959673][ C1] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2578) 
[ 49.959676][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 49.959679][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 49.959681][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 49.959685][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 49.959688][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 49.959692][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 49.959694][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 49.959696][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 49.959700][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 49.959703][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 49.959706][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 49.959710][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 49.959715][ C1] __put_net (net/core/net_namespace.c:732) 
[ 49.959719][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 49.959724][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 49.959727][ C1] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2578) 
[ 49.959730][ C1] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 49.959734][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 49.959738][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 49.959742][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 49.959746][ C1] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 49.959750][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 49.959755][ C1] handle_softirqs (kernel/softirq.c:580) 
[ 49.959760][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 49.959764][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 49.959767][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   49.959770][    C1]  </IRQ>
[   49.959771][    C1]  <TASK>
[ 49.959773][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 49.959776][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 49.959780][ C1] Code: f2 ce 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 28 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:	f2 ce                	repnz (bad)
   2:	00 c3                	add    %al,%bl
   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 17 28 00 	verw   0x281783(%rip)        # 0x2817ab
  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
[   49.959783][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000246
[   49.959786][    C1] RAX: 00000000001cd21d RBX: 1ffff92000026fc1 RCX: ffffffffafe125d9
[   49.959788][    C1] RDX: 0000000000000000 RSI: ffffffffb0aa61cd RDI: ffffffffb0258be0
[   49.959790][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c166fa
[   49.959791][    C1] R10: ffff8880360b37d3 R11: ffffffffb0c11288 R12: 0000000000000000
[   49.959793][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 49.959797][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 49.959801][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 49.959804][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 49.959806][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 49.959810][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 49.959814][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 49.959818][ C1] do_idle (kernel/sched/idle.c:325) 
[ 49.959822][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 49.959826][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 49.959829][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 49.959834][ C1] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   49.975992][    C1] RCU nest depth: 0, expected: 0
| [   49.976166][    C1] INFO: lockdep is turned off.
| [   49.976342][    C1] Preemption disabled at:
| [ 49.976344][ C1] 0x0 
[   49.976773][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   49.976775][    C1] Call Trace:
[   49.976777][    C1]  <IRQ>
[ 49.976779][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 49.976787][ C1] __might_resched (kernel/sched/core.c:8796) 
[ 49.976793][ C1] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 49.976797][ C1] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 49.976800][ C1] ? simple_recursive_removal (fs/libfs.c:614) 
[ 49.976804][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 49.976810][ 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) 
[ 49.976815][ C1] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 49.976818][ 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) 
[ 49.976821][ C1] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 49.976827][ C1] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 49.976830][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 49.976835][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 49.976839][ 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) 
[ 49.976844][ C1] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2578) 
[ 49.976849][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 49.976852][ C1] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 49.976856][ C1] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 49.976860][ C1] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 49.976864][ C1] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 49.976867][ C1] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 49.976870][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 49.976872][ C1] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 49.976877][ C1] ? do_idle (kernel/sched/idle.c:325) 
[ 49.976880][ C1] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 49.976883][ C1] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 49.976887][ C1] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 49.976893][ C1] __put_net (net/core/net_namespace.c:732) 
[ 49.976897][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 49.976901][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 49.976904][ C1] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2578) 
[ 49.976908][ C1] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 49.976912][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 49.976916][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 49.976921][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 49.976924][ C1] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 49.976929][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 49.976933][ C1] handle_softirqs (kernel/softirq.c:580) 
[ 49.976940][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 49.976943][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 49.976946][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   49.976950][    C1]  </IRQ>
[   49.976951][    C1]  <TASK>
[ 49.976952][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 49.976955][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 49.976959][ C1] Code: f2 ce 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 28 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:	f2 ce                	repnz (bad)
   2:	00 c3                	add    %al,%bl
   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 17 28 00 	verw   0x281783(%rip)        # 0x2817ab
  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
[   49.976962][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000246
[   49.976965][    C1] RAX: 00000000001cd21d RBX: 1ffff92000026fc1 RCX: ffffffffafe125d9
[   49.976967][    C1] RDX: 0000000000000000 RSI: ffffffffb0aa61cd RDI: ffffffffb0258be0
[   49.976968][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c166fa
[   49.976970][    C1] R10: ffff8880360b37d3 R11: ffffffffb0c11288 R12: 0000000000000000
[   49.976972][    C1] R13: ffff888001bf0040 R14: dffffc0000000000 R15: 0000000000000000
[ 49.976975][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 49.976980][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 49.976982][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 49.976985][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 49.976989][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 49.976993][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 49.976998][ C1] do_idle (kernel/sched/idle.c:325) 
[ 49.977002][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 49.977005][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 49.977009][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 


Finger prints:
mark_lock_irq:mark_lock:mark_usage:__lock_acquire:_raw_spin_lock
__might_resched:down_write:simple_recursive_removal:debugfs_remove:ref_tracker_dir_exit