======================================
| [ 1751.351021][    C1] 1 lock held by ksoftirqd/1/22:
| [ 1751.351198][ C1] #0: ffffffffaf188a40 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2562) 
| [ 1751.351508][    C1]
| [ 1751.351508][    C1] stack backtrace:
[ 1751.351726][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1751.351729][    C1] Call Trace:
[ 1751.351731][    C1]  <TASK>
[ 1751.351733][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 1751.351740][ C1] print_usage_bug.part.0 (kernel/locking/lockdep.c:4046) 
[ 1751.351745][ C1] mark_lock_irq (kernel/locking/lockdep.c:4011 kernel/locking/lockdep.c:4057 kernel/locking/lockdep.c:4268) 
[ 1751.351750][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 1751.351755][ C1] ? save_trace (kernel/locking/lockdep.c:594) 
[ 1751.351759][ C1] mark_lock (kernel/locking/lockdep.c:4754) 
[ 1751.351763][ C1] mark_usage (kernel/locking/lockdep.c:4643) 
[ 1751.351767][ C1] __lock_acquire (kernel/locking/lockdep.c:5189) 
[ 1751.351772][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:472 kernel/locking/lockdep.c:5868) 
[ 1751.351776][ C1] ? simple_pin_fs (fs/libfs.c:1066) 
[ 1751.351779][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 1751.351784][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5829) 
[ 1751.351787][ C1] ? simple_pin_fs (fs/libfs.c:1066) 
[ 1751.351791][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 1751.351794][ C1] ? simple_pin_fs (fs/libfs.c:1066) 
[ 1751.351796][ C1] simple_pin_fs (fs/libfs.c:1066) 
[ 1751.351800][ C1] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 1751.351804][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 1751.351809][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 1751.351812][ 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:2366) 
[ 1751.351817][ C1] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 1751.351820][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 1751.351822][ C1] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 1751.351827][ C1] ? kthread (kernel/kthread.c:464) 
[ 1751.351830][ C1] ? ret_from_fork (arch/x86/kernel/process.c:153) 
[ 1751.351833][ C1] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 1751.351836][ C1] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2417) 
[ 1751.351840][ C1] ? __pfx_migrate_enable (kernel/sched/core.c:2392) 
[ 1751.351846][ C1] __put_net (net/core/net_namespace.c:732) 
[ 1751.351850][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 1751.351853][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 1751.351856][ C1] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 1751.351860][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 1751.351865][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 1751.351867][ C1] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1059) 
[ 1751.351874][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 1751.351878][ C1] ? note_gp_changes (kernel/rcu/tree.c:1324 (discriminator 1)) 
[ 1751.351881][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 1751.351885][ C1] rcu_core (kernel/rcu/tree.c:2826) 
[ 1751.351889][ C1] handle_softirqs (kernel/softirq.c:580) 
[ 1751.351894][ C1] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 1751.351898][ C1] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 1751.351901][ C1] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 1751.351904][ C1] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 1751.351908][ C1] kthread (kernel/kthread.c:464) 
[ 1751.351911][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1751.351913][ C1] ? ret_from_fork (arch/x86/kernel/process.c:152) 
[ 1751.351917][ C1] ? __lock_release (kernel/locking/lockdep.c:5534) 
[ 1751.351920][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 1751.351924][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1751.351927][ C1] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 1751.351930][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1751.351933][ C1] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
| [ 1751.362593][    C1] RCU nest depth: 0, expected: 0
| [ 1751.362756][    C1] INFO: lockdep is turned off.
| [ 1751.362914][    C1] Preemption disabled at:
| [ 1751.362916][ C1] handle_softirqs (kernel/softirq.c:553) 
[ 1751.363253][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1751.363255][    C1] Call Trace:
[ 1751.363257][    C1]  <TASK>
[ 1751.363258][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 1751.363264][ C1] __might_resched (kernel/sched/core.c:8819) 
[ 1751.363270][ C1] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 1751.363276][ C1] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 1751.363280][ C1] ? simple_recursive_removal (./include/linux/dcache.h:345 fs/libfs.c:610) 
[ 1751.363284][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 1751.363290][ 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) 
[ 1751.363296][ C1] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:616) 
[ 1751.363299][ C1] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 1751.363305][ 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) 
[ 1751.363309][ C1] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 1751.363312][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:423 lib/ref_tracker.c:195) 
[ 1751.363317][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 1751.363319][ 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:2366) 
[ 1751.363323][ C1] ? rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 1751.363327][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 1751.363329][ C1] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 1751.363333][ C1] ? kthread (kernel/kthread.c:464) 
[ 1751.363337][ C1] ? ret_from_fork (arch/x86/kernel/process.c:153) 
[ 1751.363342][ C1] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 1751.363345][ C1] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2417) 
[ 1751.363351][ C1] ? __pfx_migrate_enable (kernel/sched/core.c:2392) 
[ 1751.363356][ C1] __put_net (net/core/net_namespace.c:732) 
[ 1751.363361][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2366) 
[ 1751.363364][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2568) 
[ 1751.363367][ C1] rcu_do_batch (./include/linux/rcupdate.h:341 kernel/rcu/tree.c:2570) 
[ 1751.363371][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 1751.363376][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2492) 
[ 1751.363379][ C1] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1059) 
[ 1751.363385][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 1751.363389][ C1] ? note_gp_changes (kernel/rcu/tree.c:1324 (discriminator 1)) 
[ 1751.363392][ C1] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 1751.363396][ C1] rcu_core (kernel/rcu/tree.c:2826) 
[ 1751.363400][ C1] handle_softirqs (kernel/softirq.c:580) 
[ 1751.363405][ C1] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 1751.363409][ C1] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 1751.363413][ C1] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 1751.363416][ C1] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 1751.363419][ C1] kthread (kernel/kthread.c:464) 
[ 1751.363422][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1751.363425][ C1] ? ret_from_fork (arch/x86/kernel/process.c:152) 
[ 1751.363428][ C1] ? __lock_release (kernel/locking/lockdep.c:5534) 
[ 1751.363433][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 1751.363436][ C1] ? __pfx_kthread (kernel/kthread.c:413) 
[ 1751.363439][ C1] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 1751.363443][ 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