======================================
| [   16.449019][    C2] 1 lock held by swapper/2/0:
| [ 16.449218][ C2] #0: ffffffff9d5749c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2562) 
| [   16.449575][    C2]
| [   16.449575][    C2] stack backtrace:
[   16.449829][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   16.449831][    C2] Call Trace:
[   16.449834][    C2]  <IRQ>
[ 16.449836][ C2] dump_stack_lvl (lib/dump_stack.c:123) 
[ 16.449843][ C2] print_usage_bug.part.0 (kernel/locking/lockdep.c:4046) 
[ 16.449849][ C2] mark_lock_irq (kernel/locking/lockdep.c:4011 kernel/locking/lockdep.c:4057 kernel/locking/lockdep.c:4268) 
[ 16.449854][ C2] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 16.449861][ C2] ? save_trace (kernel/locking/lockdep.c:594) 
[ 16.449865][ C2] mark_lock (kernel/locking/lockdep.c:4754) 
[ 16.449870][ C2] mark_usage (kernel/locking/lockdep.c:4643) 
[ 16.449874][ C2] __lock_acquire (kernel/locking/lockdep.c:5189) 
[ 16.449879][ C2] lock_acquire.part.0 (kernel/locking/lockdep.c:472 kernel/locking/lockdep.c:5868) 
[ 16.449882][ C2] ? simple_pin_fs (fs/libfs.c:1066) 
[ 16.449885][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 16.449892][ C2] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5829) 
[ 16.449894][ C2] ? simple_pin_fs (fs/libfs.c:1066) 
[ 16.449897][ C2] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 16.449900][ C2] ? simple_pin_fs (fs/libfs.c:1066) 
[ 16.449903][ C2] simple_pin_fs (fs/libfs.c:1066) 
[ 16.449906][ C2] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 16.449909][ C2] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 16.449915][ C2] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 16.449918][ C2] ? __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:2366) 
[ 16.449925][ C2] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 16.449928][ C2] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 16.449931][ C2] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 16.449933][ C2] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[ 16.449939][ C2] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 16.449943][ C2] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:81) 
[ 16.449946][ C2] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:748) 
[ 16.449948][ C2] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 16.449951][ C2] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 16.449957][ C2] ? do_idle (kernel/sched/idle.c:325) 
[ 16.449961][ C2] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 16.449964][ C2] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 16.449969][ C2] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 16.449977][ C2] __put_net (net/core/net_namespace.c:732) 
[ 16.449981][ C2] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 16.449985][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 16.449988][ C2] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 16.449992][ C2] ? find_held_lock (kernel/locking/lockdep.c:5348) 
[ 16.449997][ C2] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 16.450000][ C2] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 16.450004][ C2] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 16.450007][ C2] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 16.450012][ C2] rcu_core (kernel/rcu/tree.c:2826) 
[ 16.450016][ C2] handle_softirqs (kernel/softirq.c:579) 
[ 16.450021][ C2] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 16.450024][ C2] irq_exit_rcu (kernel/softirq.c:698) 
[ 16.450026][ C2] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[   16.450030][    C2]  </IRQ>
[   16.450031][    C2]  <TASK>
[ 16.450032][ C2] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 16.450035][ C2] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:81) 
[ 16.450040][ C2] Code: 60 b8 00 e9 c3 57 02 00 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 c3 75 13 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
All code
========
   0:	60                   	(bad)
   1:	b8 00 e9 c3 57       	mov    $0x57c3e900,%eax
   6:	02 00                	add    (%rax),%al
   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 c3 75 13 00 	verw   0x1375c3(%rip)        # 0x1375eb
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	c3                   	ret		<-- trapping instruction
  2b:	cc                   	int3
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  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:	c3                   	ret
   1:	cc                   	int3
   2:	cc                   	int3
   3:	cc                   	int3
   4:	cc                   	int3
   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
[   16.450043][    C2] RSP: 0018:ffffc90000147de8 EFLAGS: 00000242
[   16.450046][    C2] RAX: 000000000004ee2f RBX: 1ffff92000028fc1 RCX: ffffffff9c55ba19
[   16.450048][    C2] RDX: 0000000000000000 RSI: ffffffff9d087785 RDI: ffffffff9c851260
[   16.450050][    C2] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c2667a
[   16.450052][    C2] R10: ffff8880361333d3 R11: 0000000000000000 R12: 0000000000000000
[   16.450054][    C2] R13: ffff888001bf2340 R14: dffffc0000000000 R15: 0000000000000000
[ 16.450058][ C2] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 16.450062][ C2] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:748) 
[ 16.450064][ C2] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 16.450067][ C2] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 16.450071][ C2] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 16.450075][ C2] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 16.450081][ C2] do_idle (kernel/sched/idle.c:325) 
[ 16.450084][ C2] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 16.450088][ C2] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 16.450092][ C2] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 16.450097][ C2] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   16.466737][    C2] RCU nest depth: 0, expected: 0
| [   16.466942][    C2] INFO: lockdep is turned off.
| [   16.467150][    C2] Preemption disabled at:
| [ 16.467152][ C2] 0x0 
[   16.467508][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   16.467510][    C2] Call Trace:
[   16.467512][    C2]  <IRQ>
[ 16.467514][ C2] dump_stack_lvl (lib/dump_stack.c:123) 
[ 16.467522][ C2] __might_resched (kernel/sched/core.c:8819) 
[ 16.467529][ C2] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 16.467534][ C2] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 16.467537][ C2] ? simple_recursive_removal (./include/linux/dcache.h:345 fs/libfs.c:610) 
[ 16.467542][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 16.467549][ C2] ? 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) 
[ 16.467555][ C2] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:616) 
[ 16.467558][ C2] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 16.467564][ C2] ? 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) 
[ 16.467568][ C2] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 16.467571][ C2] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 16.467577][ C2] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 16.467580][ C2] ? __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:2366) 
[ 16.467587][ C2] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 16.467591][ C2] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 16.467594][ C2] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 16.467599][ C2] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[ 16.467603][ C2] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 16.467608][ C2] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:81) 
[ 16.467611][ C2] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:748) 
[ 16.467613][ C2] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 16.467616][ C2] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 16.467621][ C2] ? do_idle (kernel/sched/idle.c:325) 
[ 16.467624][ C2] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 16.467627][ C2] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 16.467633][ C2] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 16.467639][ C2] __put_net (net/core/net_namespace.c:732) 
[ 16.467643][ C2] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 16.467647][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 16.467650][ C2] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 16.467654][ C2] ? find_held_lock (kernel/locking/lockdep.c:5348) 
[ 16.467659][ C2] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 16.467663][ C2] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 16.467668][ C2] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 16.467671][ C2] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 16.467676][ C2] rcu_core (kernel/rcu/tree.c:2826) 
[ 16.467680][ C2] handle_softirqs (kernel/softirq.c:579) 
[ 16.467685][ C2] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 16.467688][ C2] irq_exit_rcu (kernel/softirq.c:698) 
[ 16.467690][ C2] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[   16.467694][    C2]  </IRQ>
[   16.467695][    C2]  <TASK>
[ 16.467697][ C2] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 16.467700][ C2] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:81) 
[ 16.467704][ C2] Code: 60 b8 00 e9 c3 57 02 00 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 c3 75 13 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
All code
========
   0:	60                   	(bad)
   1:	b8 00 e9 c3 57       	mov    $0x57c3e900,%eax
   6:	02 00                	add    (%rax),%al
   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 c3 75 13 00 	verw   0x1375c3(%rip)        # 0x1375eb
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	c3                   	ret		<-- trapping instruction
  2b:	cc                   	int3
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  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:	c3                   	ret
   1:	cc                   	int3
   2:	cc                   	int3
   3:	cc                   	int3
   4:	cc                   	int3
   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
[   16.467707][    C2] RSP: 0018:ffffc90000147de8 EFLAGS: 00000242
[   16.467710][    C2] RAX: 000000000004ee2f RBX: 1ffff92000028fc1 RCX: ffffffff9c55ba19
[   16.467712][    C2] RDX: 0000000000000000 RSI: ffffffff9d087785 RDI: ffffffff9c851260
[   16.467714][    C2] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c2667a
[   16.467716][    C2] R10: ffff8880361333d3 R11: 0000000000000000 R12: 0000000000000000
[   16.467718][    C2] R13: ffff888001bf2340 R14: dffffc0000000000 R15: 0000000000000000
[ 16.467722][ C2] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 16.467726][ C2] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:748) 
[ 16.467728][ C2] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 16.467731][ C2] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 16.467735][ C2] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 16.467739][ C2] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:59) 
[ 16.467744][ C2] do_idle (kernel/sched/idle.c:325) 
[ 16.467748][ C2] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 16.467752][ C2] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 16.467755][ C2] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 
[ 16.467760][ C2] common_startup_64 (arch/x86/kernel/head_64.S:419) 
| [   18.756533][    C2] INFO: lockdep is turned off.
| [   18.756729][    C2] Preemption disabled at:
| [ 18.756731][ C2] handle_softirqs (kernel/softirq.c:553) 
| [   18.757137][    C2] Tainted: [W]=WARN
[   18.757138][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   18.757141][    C2] Call Trace:
[   18.757143][    C2]  <TASK>
[ 18.757145][ C2] dump_stack_lvl (lib/dump_stack.c:123) 
[ 18.757154][ C2] __might_resched (kernel/sched/core.c:8819) 
[ 18.757162][ C2] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 18.757168][ C2] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 18.757171][ C2] ? simple_recursive_removal (./include/linux/dcache.h:345 fs/libfs.c:610) 
[ 18.757177][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 18.757186][ C2] ? 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) 
[ 18.757191][ C2] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:616) 
[ 18.757194][ C2] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 18.757200][ C2] ? 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) 
[ 18.757205][ C2] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 18.757208][ C2] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 18.757215][ C2] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 18.757218][ C2] ? __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:2366) 
[ 18.757225][ C2] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 18.757230][ C2] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 18.757233][ C2] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 18.757238][ C2] ? kthread (kernel/kthread.c:464) 
[ 18.757244][ C2] ? ret_from_fork (arch/x86/kernel/process.c:153) 
[ 18.757247][ C2] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 18.757254][ C2] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2417) 
[ 18.757260][ C2] ? __pfx_migrate_enable (kernel/sched/core.c:2392) 
[ 18.757264][ C2] ? bpf_sk_storage_free (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:871 net/core/bpf_sk_storage.c:61) 
[ 18.757269][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 18.757274][ C2] __put_net (net/core/net_namespace.c:732) 
[ 18.757278][ C2] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 18.757282][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 18.757285][ C2] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 18.757291][ C2] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 18.757295][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 18.757299][ C2] ? trace_irq_enable.constprop.0 (./include/trace/events/preemptirq.h:40) 
[ 18.757306][ C2] rcu_core (kernel/rcu/tree.c:2826) 
[ 18.757310][ C2] handle_softirqs (kernel/softirq.c:579) 
[ 18.757314][ C2] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 18.757317][ C2] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 18.757320][ C2] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 18.757323][ C2] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 18.757327][ C2] kthread (kernel/kthread.c:464) 
[ 18.757330][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 18.757333][ C2] ? ret_from_fork (arch/x86/kernel/process.c:152) 
[ 18.757335][ C2] ? __lock_release (kernel/locking/lockdep.c:5534) 
[ 18.757337][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 18.757341][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 18.757345][ C2] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 18.757347][ C2] ? __pfx_kthread (kernel/kthread.c:413) 


Finger prints:
handle_softirqs:dump_stack_lvl:__might_resched:down_write:simple_recursive_removal
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