======================================
| [   14.175016][    C3] 1 lock held by ksoftirqd/3/32:
| [ 14.175196][ C3] #0: ffffffffbc7774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   14.175517][    C3]
| [   14.175517][    C3] stack backtrace:
[   14.175773][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   14.175775][    C3] Call Trace:
[   14.175777][    C3]  <TASK>
[ 14.175780][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 14.175787][ C3] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 14.175793][ C3] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 14.175798][ C3] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 14.175803][ C3] ? save_trace (kernel/locking/lockdep.c:595) 
[ 14.175807][ C3] mark_lock (kernel/locking/lockdep.c:4756) 
[ 14.175811][ C3] mark_usage (kernel/locking/lockdep.c:4645) 
[ 14.175815][ C3] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 14.175818][ C3] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 14.175823][ C3] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 14.175826][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 14.175830][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.175836][ C3] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 14.175838][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 14.175842][ C3] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 14.175846][ C3] ? simple_pin_fs (fs/libfs.c:1067) 
[ 14.175848][ C3] simple_pin_fs (fs/libfs.c:1067) 
[ 14.175851][ C3] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 14.175856][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 14.175863][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 14.175867][ 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) 
[ 14.175873][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.175876][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 14.175878][ C3] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.175881][ C3] ? kthread (kernel/kthread.c:464) 
[ 14.175885][ C3] ? ret_from_fork (arch/x86/kernel/process.c:148) 
[ 14.175889][ C3] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 14.175892][ C3] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2427) 
[ 14.175897][ C3] ? __pfx_migrate_enable (kernel/sched/core.c:2402) 
[ 14.175903][ C3] __put_net (net/core/net_namespace.c:732) 
[ 14.175907][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 14.175911][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.175914][ C3] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.175917][ C3] ? sched_balance_domains (kernel/sched/fair.c:12268) 
[ 14.175923][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 14.175927][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.175930][ C3] ? note_gp_changes (kernel/rcu/tree.c:1326 (discriminator 1)) 
[ 14.175933][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 14.175939][ C3] rcu_core (kernel/rcu/tree.c:2834) 
[ 14.175944][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 14.175949][ C3] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 14.175953][ C3] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 14.175956][ C3] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.175959][ C3] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 14.175963][ C3] kthread (kernel/kthread.c:464) 
[ 14.175966][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.175968][ C3] ? ret_from_fork (arch/x86/kernel/process.c:147) 
[ 14.175971][ C3] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 14.175975][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.175978][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.175981][ C3] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 14.175984][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.175987][ C3] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
| [   14.187070][    C3] RCU nest depth: 0, expected: 0
| [   14.187270][    C3] INFO: lockdep is turned off.
| [   14.187425][    C3] Preemption disabled at:
| [ 14.187427][ C3] handle_softirqs (kernel/softirq.c:553) 
[   14.187803][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   14.187806][    C3] Call Trace:
[   14.187807][    C3]  <TASK>
[ 14.187810][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 14.187817][ C3] __might_resched (kernel/sched/core.c:8796) 
[ 14.187826][ C3] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 14.187830][ C3] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 14.187833][ C3] ? simple_recursive_removal (fs/libfs.c:614) 
[ 14.187838][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.187844][ 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) 
[ 14.187848][ C3] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 14.187851][ 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) 
[ 14.187853][ C3] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 14.187860][ C3] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 14.187863][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 14.187868][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 14.187870][ 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) 
[ 14.187875][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.187879][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 14.187882][ C3] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.187885][ C3] ? kthread (kernel/kthread.c:464) 
[ 14.187888][ C3] ? ret_from_fork (arch/x86/kernel/process.c:148) 
[ 14.187893][ C3] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 14.187897][ C3] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2427) 
[ 14.187901][ C3] ? __pfx_migrate_enable (kernel/sched/core.c:2402) 
[ 14.187907][ C3] __put_net (net/core/net_namespace.c:732) 
[ 14.187911][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 14.187915][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.187918][ C3] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.187921][ C3] ? sched_balance_domains (kernel/sched/fair.c:12268) 
[ 14.187927][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 14.187931][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.187934][ C3] ? note_gp_changes (kernel/rcu/tree.c:1326 (discriminator 1)) 
[ 14.187937][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 14.187943][ C3] rcu_core (kernel/rcu/tree.c:2834) 
[ 14.187947][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 14.187952][ C3] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 14.187956][ C3] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 14.187959][ C3] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.187962][ C3] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 14.187965][ C3] kthread (kernel/kthread.c:464) 
[ 14.187968][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.187970][ C3] ? ret_from_fork (arch/x86/kernel/process.c:147) 
[ 14.187973][ C3] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 14.187978][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.187982][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.187985][ C3] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 14.187988][ C3] ? __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