======================================
| [ 1746.812618][    C1] 1 lock held by ksoftirqd/1/22:
| [ 1746.812793][ C1] #0: ffffffff8798b540 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [ 1746.813105][    C1]
| [ 1746.813105][    C1] stack backtrace:
[ 1746.813329][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1746.813332][    C1] Call Trace:
[ 1746.813334][    C1]  <TASK>
[ 1746.813336][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 1746.813344][ C1] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 1746.813349][ C1] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 1746.813353][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 1746.813357][ C1] ? save_trace (kernel/locking/lockdep.c:595) 
[ 1746.813363][ C1] mark_lock (kernel/locking/lockdep.c:4756) 
[ 1746.813367][ C1] mark_usage (kernel/locking/lockdep.c:4645) 
[ 1746.813369][ C1] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 1746.813375][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 1746.813377][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 1746.813381][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 1746.813385][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 1746.813387][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 1746.813391][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 1746.813394][ C1] ? simple_pin_fs (fs/libfs.c:1067) 
[ 1746.813397][ C1] simple_pin_fs (fs/libfs.c:1067) 
[ 1746.813400][ C1] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 1746.813403][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 1746.813409][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 1746.813411][ 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) 
[ 1746.813417][ C1] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2578) 
[ 1746.813420][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 1746.813423][ C1] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 1746.813432][ C1] ? kthread (kernel/kthread.c:464) 
[ 1746.813436][ C1] ? ret_from_fork (arch/x86/kernel/process.c:148) 
[ 1746.813438][ C1] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 1746.813442][ C1] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2427) 
[ 1746.813446][ C1] ? __pfx_migrate_enable (kernel/sched/core.c:2402) 
[ 1746.813451][ C1] __put_net (net/core/net_namespace.c:732) 
[ 1746.813458][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 1746.813461][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 1746.813464][ C1] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2578) 
[ 1746.813470][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 1746.813474][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 1746.813477][ C1] ? note_gp_changes (kernel/rcu/tree.c:1326 (discriminator 1)) 
[ 1746.813480][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 1746.813486][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 1746.813491][ C1] handle_softirqs (kernel/softirq.c:580) 
[ 1746.813495][ C1] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 1746.813499][ C1] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 1746.813501][ C1] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 1746.813505][ C1] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 1746.813509][ C1] kthread (kernel/kthread.c:464) 
[ 1746.813512][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1746.813515][ C1] ? ret_from_fork (arch/x86/kernel/process.c:147) 
[ 1746.813518][ C1] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 1746.813521][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 1746.813524][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1746.813527][ C1] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 1746.813530][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1746.813533][ C1] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
| [ 1746.823751][    C1] RCU nest depth: 0, expected: 0
| [ 1746.823910][    C1] INFO: lockdep is turned off.
| [ 1746.824070][    C1] Preemption disabled at:
| [ 1746.824072][ C1] handle_softirqs (kernel/softirq.c:553) 
[ 1746.824411][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1746.824414][    C1] Call Trace:
[ 1746.824415][    C1]  <TASK>
[ 1746.824417][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 1746.824424][ C1] __might_resched (kernel/sched/core.c:8796) 
[ 1746.824432][ C1] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 1746.824436][ C1] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 1746.824439][ C1] ? simple_recursive_removal (fs/libfs.c:614) 
[ 1746.824443][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 1746.824447][ 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) 
[ 1746.824453][ C1] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 1746.824456][ 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) 
[ 1746.824460][ C1] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 1746.824466][ C1] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 1746.824469][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:412 lib/ref_tracker.c:196) 
[ 1746.824474][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:254) 
[ 1746.824477][ 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) 
[ 1746.824481][ C1] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2578) 
[ 1746.824485][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:190) 
[ 1746.824488][ C1] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 1746.824491][ C1] ? kthread (kernel/kthread.c:464) 
[ 1746.824495][ C1] ? ret_from_fork (arch/x86/kernel/process.c:148) 
[ 1746.824499][ C1] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 1746.824503][ C1] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2427) 
[ 1746.824506][ C1] ? __pfx_migrate_enable (kernel/sched/core.c:2402) 
[ 1746.824511][ C1] __put_net (net/core/net_namespace.c:732) 
[ 1746.824515][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 1746.824518][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 1746.824521][ C1] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2578) 
[ 1746.824527][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 1746.824531][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 1746.824534][ C1] ? note_gp_changes (kernel/rcu/tree.c:1326 (discriminator 1)) 
[ 1746.824536][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 1746.824542][ C1] rcu_core (kernel/rcu/tree.c:2834) 
[ 1746.824547][ C1] handle_softirqs (kernel/softirq.c:580) 
[ 1746.824551][ C1] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 1746.824554][ C1] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 1746.824557][ C1] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 1746.824560][ C1] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 1746.824564][ C1] kthread (kernel/kthread.c:464) 
[ 1746.824568][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1746.824571][ C1] ? ret_from_fork (arch/x86/kernel/process.c:147) 
[ 1746.824573][ C1] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 1746.824577][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 1746.824580][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1746.824584][ C1] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 1746.824586][ C1] ? __pfx_kthread (kernel/kthread.c:413) 


Finger prints:
mark_lock_irq:mark_lock:mark_usage:__lock_acquire:_raw_spin_lock
handle_softirqs:dump_stack_lvl:__might_resched:down_write:simple_recursive_removal