======================================
| [   14.301041][    C3] 1 lock held by ksoftirqd/3/32:
| [ 14.301226][ C3] #0: ffffffff99b749c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2562) 
| [   14.301547][    C3]
| [   14.301547][    C3] stack backtrace:
[   14.301788][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   14.301790][    C3] Call Trace:
[   14.301792][    C3]  <TASK>
[ 14.301794][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 14.301801][ C3] print_usage_bug.part.0 (kernel/locking/lockdep.c:4046) 
[ 14.301805][ C3] mark_lock_irq (kernel/locking/lockdep.c:4011 kernel/locking/lockdep.c:4057 kernel/locking/lockdep.c:4268) 
[ 14.301809][ C3] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 14.301814][ C3] ? save_trace (kernel/locking/lockdep.c:594) 
[ 14.301820][ C3] mark_lock (kernel/locking/lockdep.c:4754) 
[ 14.301823][ C3] mark_usage (kernel/locking/lockdep.c:4643) 
[ 14.301826][ C3] __lock_acquire (kernel/locking/lockdep.c:5189) 
[ 14.301831][ C3] lock_acquire.part.0 (kernel/locking/lockdep.c:472 kernel/locking/lockdep.c:5868) 
[ 14.301833][ C3] ? simple_pin_fs (fs/libfs.c:1066) 
[ 14.301838][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 14.301841][ C3] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5829) 
[ 14.301843][ C3] ? simple_pin_fs (fs/libfs.c:1066) 
[ 14.301847][ C3] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 14.301850][ C3] ? simple_pin_fs (fs/libfs.c:1066) 
[ 14.301853][ C3] simple_pin_fs (fs/libfs.c:1066) 
[ 14.301856][ C3] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 14.301860][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 14.301866][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 14.301870][ 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:2366) 
[ 14.301875][ C3] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 14.301878][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 14.301882][ C3] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.301887][ C3] ? kthread (kernel/kthread.c:464) 
[ 14.301892][ C3] ? ret_from_fork (arch/x86/kernel/process.c:153) 
[ 14.301894][ C3] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 14.301898][ C3] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2417) 
[ 14.301901][ C3] ? __pfx_migrate_enable (kernel/sched/core.c:2392) 
[ 14.301906][ C3] __put_net (net/core/net_namespace.c:732) 
[ 14.301910][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 14.301914][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 14.301917][ C3] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 14.301923][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 14.301927][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 14.301930][ C3] ? note_gp_changes (kernel/rcu/tree.c:1324 (discriminator 1)) 
[ 14.301933][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 14.301938][ C3] rcu_core (kernel/rcu/tree.c:2826) 
[ 14.301943][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 14.301947][ C3] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 14.301951][ C3] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 14.301953][ C3] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.301957][ C3] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 14.301961][ C3] kthread (kernel/kthread.c:464) 
[ 14.301965][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.301968][ C3] ? ret_from_fork (arch/x86/kernel/process.c:152) 
[ 14.301970][ C3] ? __lock_release (kernel/locking/lockdep.c:5534) 
[ 14.301973][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 14.301976][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.301980][ C3] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 14.301982][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.301986][ C3] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
| [   14.313482][    C3] RCU nest depth: 0, expected: 0
| [   14.313655][    C3] INFO: lockdep is turned off.
| [   14.313827][    C3] Preemption disabled at:
| [ 14.313829][ C3] handle_softirqs (kernel/softirq.c:553) 
[   14.314179][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   14.314181][    C3] Call Trace:
[   14.314183][    C3]  <TASK>
[ 14.314186][ C3] dump_stack_lvl (lib/dump_stack.c:123) 
[ 14.314193][ C3] __might_resched (kernel/sched/core.c:8819) 
[ 14.314199][ C3] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 14.314203][ C3] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 14.314205][ C3] ? simple_recursive_removal (./include/linux/dcache.h:345 fs/libfs.c:610) 
[ 14.314211][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 14.314215][ 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) 
[ 14.314220][ C3] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:616) 
[ 14.314223][ C3] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 14.314228][ 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) 
[ 14.314233][ C3] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 14.314236][ C3] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 14.314241][ C3] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 14.314245][ 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:2366) 
[ 14.314250][ C3] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 14.314255][ C3] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 14.314258][ C3] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.314262][ C3] ? kthread (kernel/kthread.c:464) 
[ 14.314267][ C3] ? ret_from_fork (arch/x86/kernel/process.c:153) 
[ 14.314270][ C3] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 14.314275][ C3] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2417) 
[ 14.314279][ C3] ? __pfx_migrate_enable (kernel/sched/core.c:2392) 
[ 14.314284][ C3] __put_net (net/core/net_namespace.c:732) 
[ 14.314287][ C3] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 14.314291][ C3] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 14.314295][ C3] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 14.314301][ C3] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 14.314305][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 14.314307][ C3] ? note_gp_changes (kernel/rcu/tree.c:1324 (discriminator 1)) 
[ 14.314310][ C3] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 14.314316][ C3] rcu_core (kernel/rcu/tree.c:2826) 
[ 14.314319][ C3] handle_softirqs (kernel/softirq.c:579) 
[ 14.314323][ C3] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 14.314327][ C3] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 14.314330][ C3] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.314333][ C3] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 14.314337][ C3] kthread (kernel/kthread.c:464) 
[ 14.314341][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.314344][ C3] ? ret_from_fork (arch/x86/kernel/process.c:152) 
[ 14.314346][ C3] ? __lock_release (kernel/locking/lockdep.c:5534) 
[ 14.314349][ C3] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 14.314352][ C3] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.314356][ C3] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 14.314358][ 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