======================================
| [   14.114433][    C0] 1 lock held by ksoftirqd/0/14:
| [ 14.114750][ C0] #0: ffffffff8b7774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   14.115326][    C0]
| [   14.115326][    C0] stack backtrace:
[   14.115746][    C0] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   14.115750][    C0] Call Trace:
[   14.115753][    C0]  <TASK>
[ 14.115758][ C0] dump_stack_lvl (lib/dump_stack.c:123) 
[ 14.115770][ C0] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 14.115780][ C0] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 14.115789][ C0] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 14.115800][ C0] ? save_trace (kernel/locking/lockdep.c:595) 
[ 14.115807][ C0] mark_lock (kernel/locking/lockdep.c:4756) 
[ 14.115814][ C0] mark_usage (kernel/locking/lockdep.c:4645) 
[ 14.115820][ C0] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 14.115825][ C0] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 14.115833][ C0] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 14.115839][ C0] ? simple_pin_fs (fs/libfs.c:1067) 
[ 14.115846][ C0] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.115855][ C0] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 14.115859][ C0] ? simple_pin_fs (fs/libfs.c:1067) 
[ 14.115865][ C0] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 14.115871][ C0] ? simple_pin_fs (fs/libfs.c:1067) 
[ 14.115875][ C0] simple_pin_fs (fs/libfs.c:1067) 
[ 14.115881][ C0] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 14.115888][ C0] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 14.115898][ C0] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 14.115903][ C0] ? __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) 
[ 14.115912][ C0] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.115917][ C0] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 14.115922][ C0] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.115928][ C0] ? kthread (kernel/kthread.c:464) 
[ 14.115935][ C0] ? ret_from_fork (arch/x86/kernel/process.c:148) 
[ 14.115942][ C0] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 14.115948][ C0] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2427) 
[ 14.115957][ C0] ? __pfx_migrate_enable (kernel/sched/core.c:2402) 
[ 14.115967][ C0] __put_net (net/core/net_namespace.c:732) 
[ 14.115975][ C0] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 14.115982][ C0] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.115987][ C0] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.115997][ C0] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 14.116004][ C0] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.116009][ C0] ? note_gp_changes (kernel/rcu/tree.c:1326 (discriminator 1)) 
[ 14.116014][ C0] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 14.116025][ C0] rcu_core (kernel/rcu/tree.c:2834) 
[ 14.116035][ C0] handle_softirqs (kernel/softirq.c:579) 
[ 14.116045][ C0] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 14.116052][ C0] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 14.116057][ C0] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.116062][ C0] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 14.116067][ C0] kthread (kernel/kthread.c:464) 
[ 14.116073][ C0] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.116077][ C0] ? ret_from_fork (arch/x86/kernel/process.c:147) 
[ 14.116082][ C0] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 14.116088][ C0] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.116094][ C0] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.116101][ C0] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 14.116105][ C0] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.116110][ C0] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
| [   14.137877][    C0] RCU nest depth: 0, expected: 0
| [   14.138186][    C0] INFO: lockdep is turned off.
| [   14.138463][    C0] Preemption disabled at:
| [ 14.138466][ C0] handle_softirqs (kernel/softirq.c:553) 
[   14.139459][    C0] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   14.139462][    C0] Call Trace:
[   14.139466][    C0]  <TASK>
[ 14.139470][ C0] dump_stack_lvl (lib/dump_stack.c:123) 
[ 14.139481][ C0] __might_resched (kernel/sched/core.c:8796) 
[ 14.139495][ C0] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 14.139503][ C0] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 14.139508][ C0] ? simple_recursive_removal (fs/libfs.c:614) 
[ 14.139516][ C0] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.139525][ C0] ? 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) 
[ 14.139533][ C0] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 14.139538][ C0] ? 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) 
[ 14.139543][ C0] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 14.139551][ C0] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 14.139556][ C0] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 14.139563][ C0] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 14.139568][ C0] ? __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) 
[ 14.139592][ C0] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.139601][ C0] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 14.139604][ C0] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.139609][ C0] ? kthread (kernel/kthread.c:464) 
[ 14.139614][ C0] ? ret_from_fork (arch/x86/kernel/process.c:148) 
[ 14.139622][ C0] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 14.139627][ C0] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2427) 
[ 14.139633][ C0] ? __pfx_migrate_enable (kernel/sched/core.c:2402) 
[ 14.139641][ C0] __put_net (net/core/net_namespace.c:732) 
[ 14.139647][ C0] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 14.139654][ C0] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.139659][ C0] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 14.139668][ C0] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 14.139675][ C0] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.139680][ C0] ? note_gp_changes (kernel/rcu/tree.c:1326 (discriminator 1)) 
[ 14.139686][ C0] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 14.139695][ C0] rcu_core (kernel/rcu/tree.c:2834) 
[ 14.139702][ C0] handle_softirqs (kernel/softirq.c:579) 
[ 14.139711][ C0] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 14.139718][ C0] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 14.139723][ C0] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 14.139729][ C0] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 14.139735][ C0] kthread (kernel/kthread.c:464) 
[ 14.139741][ C0] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.139745][ C0] ? ret_from_fork (arch/x86/kernel/process.c:147) 
[ 14.139750][ C0] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 14.139759][ C0] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 14.139765][ C0] ? __pfx_kthread (kernel/kthread.c:413) 
[ 14.139771][ C0] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 14.139775][ C0] ? __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