======================================
| [  355.901040][    C3] RCU nest depth: 0, expected: 0
| [  355.901124][    C3] INFO: lockdep is turned off.
| [  355.901212][    C3] Preemption disabled at:
| [  355.901213][    C3] 0x0
[  355.901362][    C3] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  355.901364][    C3] Call Trace:
[  355.901366][    C3]  <IRQ>
[  355.901367][    C3]  dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)
[  355.901375][    C3]  __might_resched.cold (kernel/sched/core.c:9163)
[  355.901379][    C3]  ? process_output_block (drivers/tty/n_tty.c:557)
[  355.901383][    C3]  ? perf_trace_sched_switch (./include/linux/list.h:1021 (discriminator 3))
[  355.901387][    C3]  ? new_sync_write (fs/read_write.c:595)
[  355.901390][    C3]  ? ksys_write (fs/read_write.c:740)
[  355.901392][    C3]  ? do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[  355.901394][    C3]  ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
[  355.901397][    C3]  __mutex_lock (kernel/locking/mutex.c:623 kernel/locking/mutex.c:820)
[  355.901399][    C3]  ? __tcf_chain_put (net/sched/cls_api.c:694)
[  355.901403][    C3]  ? ww_mutex_lock (kernel/locking/mutex.c:933)
[  355.901406][    C3]  ? __tcf_chain_put (net/sched/cls_api.c:694)
[  355.901408][    C3]  __tcf_chain_put (net/sched/cls_api.c:694)
[  355.901409][    C3]  ? free_percpu.part.0 (./include/linux/spinlock.h:408 (discriminator 3) mm/percpu.c:2283 (discriminator 3))
[  355.901413][    C3]  tcf_action_rcu_free (net/sched/act_api.c:130 net/sched/act_api.c:370 net/sched/act_api.c:378)
[  355.901414][    C3]  ? rcu_do_batch (./include/linux/rcupdate.h:310 (discriminator 2) kernel/rcu/tree.c:2619 (discriminator 2))
[  355.901418][    C3]  rcu_do_batch (kernel/rcu/tree.c:2617)
[  355.901420][    C3]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  355.901422][    C3]  ? sched_balance_softirq (kernel/sched/fair.c:13350)
[  355.901425][    C3]  ? trace_rcu_batch_end (./include/trace/events/rcu.h:714 (discriminator 19))
[  355.901426][    C3]  ? sched_balance_domains (kernel/sched/fair.c:12634)
[  355.901428][    C3]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  355.901430][    C3]  ? trace_irq_enable.constprop.0 (./include/trace/events/preemptirq.h:40 (discriminator 22))
[  355.901433][    C3]  ? trace_irq_disable.constprop.0 (./include/trace/events/preemptirq.h:36 (discriminator 22))
[  355.901435][    C3]  rcu_core (kernel/rcu/tree.c:2869)
[  355.901436][    C3]  handle_softirqs (kernel/softirq.c:622)
[  355.901439][    C3]  ? clockevents_tick_resume (kernel/time/clockevents.c:193)
[  355.901442][    C3]  ? _local_bh_enable (kernel/softirq.c:405 (discriminator 1))
[  355.901444][    C3]  ? lock_release (./include/trace/events/lock.h:69 (discriminator 22) kernel/locking/lockdep.c:5879 (discriminator 22))
[  355.901446][    C3]  __irq_exit_rcu (kernel/softirq.c:656 kernel/softirq.c:496 kernel/softirq.c:735)
[  355.901447][    C3]  irq_exit_rcu (kernel/softirq.c:752)
[  355.901449][    C3]  sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1061 (discriminator 37) arch/x86/kernel/apic/apic.c:1061 (discriminator 37))
[  355.901451][    C3]  </IRQ>
[  355.901452][    C3]  <TASK>
[  355.901453][    C3]  asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:697)
[  355.901457][    C3] RIP: 0010:_raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:178 (discriminator 12) kernel/locking/spinlock.c:198 (discriminator 12))
[  355.901460][    C3] Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 21 7e ca fd 48 89 df e8 a9 d4 ca fd f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f <bf> 01 00 00 00 e8 30 62 bd fd 65 8b 05 29 0a fe 01 85 c0 74 12 5b
All code
========
   0:	f5                   	cmc
   1:	53                   	push   %rbx
   2:	48 8b 74 24 10       	mov    0x10(%rsp),%rsi
   7:	48 89 fb             	mov    %rdi,%rbx
   a:	48 83 c7 18          	add    $0x18,%rdi
   e:	e8 21 7e ca fd       	call   0xfffffffffdca7e34
  13:	48 89 df             	mov    %rbx,%rdi
  16:	e8 a9 d4 ca fd       	call   0xfffffffffdcad4c4
  1b:	f7 c5 00 02 00 00    	test   $0x200,%ebp
  21:	75 1f                	jne    0x42
  23:	9c                   	pushf
  24:	58                   	pop    %rax
  25:	f6 c4 02             	test   $0x2,%ah
  28:	75 2f                	jne    0x59
  2a:*	bf 01 00 00 00       	mov    $0x1,%edi		<-- trapping instruction
  2f:	e8 30 62 bd fd       	call   0xfffffffffdbd6264
  34:	65 8b 05 29 0a fe 01 	mov    %gs:0x1fe0a29(%rip),%eax        # 0x1fe0a64
  3b:	85 c0                	test   %eax,%eax
  3d:	74 12                	je     0x51
  3f:	5b                   	pop    %rbx

Code starting with the faulting instruction
===========================================
   0:	bf 01 00 00 00       	mov    $0x1,%edi
   5:	e8 30 62 bd fd       	call   0xfffffffffdbd623a
   a:	65 8b 05 29 0a fe 01 	mov    %gs:0x1fe0a29(%rip),%eax        # 0x1fe0a3a
  11:	85 c0                	test   %eax,%eax
  13:	74 12                	je     0x27
  15:	5b                   	pop    %rbx
[  355.901462][    C3] RSP: 0018:ffa0000002c3fa78 EFLAGS: 00000246
[  355.901465][    C3] RAX: 0000000000000046 RBX: ffffffff9d1137a0 RCX: 0000000000000000
[  355.901466][    C3] RDX: 0000000000000003 RSI: ffffffff9986f640 RDI: ffffffff99490613
[  355.901467][    C3] RBP: 0000000000000286 R08: ffffffff973b3820 R09: 1ffffffff3587d1a
[  355.901468][    C3] R10: 0000000000000003 R11: 0000000000000000 R12: ffffffff9d1138a8
[  355.901469][    C3] R13: 0000000000000001 R14: ffffffff9d1138e0 R15: ff11000004ad4c00
[  355.901470][    C3]  ? trace_irq_enable.constprop.0 (./include/linux/instrumented.h:82 ./include/asm-generic/bitops/instrumented-non-atomic.h:141 ./include/linux/cpumask.h:649 ./include/linux/cpumask.h:1231 ./include/trace/events/preemptirq.h:40)
[  355.901472][    C3]  ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:178 (discriminator 6) kernel/locking/spinlock.c:198 (discriminator 6))
[  355.901474][    C3]  uart_write (./include/linux/spinlock.h:408 (discriminator 3) ./include/linux/serial_core.h:788 (discriminator 3) drivers/tty/serial/serial_core.c:91 (discriminator 3) drivers/tty/serial/serial_core.c:88 (discriminator 3) drivers/tty/serial/serial_core.c:634 (discriminator 3))
[  355.901477][    C3]  process_output_block (drivers/tty/n_tty.c:557)
[  355.901479][    C3]  ? trace_irq_enable.constprop.0 (./include/trace/events/preemptirq.h:40 (discriminator 22))
[  355.901480][    C3]  ? do_raw_spin_unlock (./include/linux/instrumented.h:82 ./include/linux/atomic/atomic-instrumented.h:32 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141)
[  355.901483][    C3]  n_tty_write (drivers/tty/n_tty.c:2366)
[  355.901485][    C3]  ? n_tty_receive_signal_char (drivers/tty/n_tty.c:1188)
[  355.901487][    C3]  ? _mutex_trylock_nest_lock (kernel/locking/mutex.c:1180 (discriminator 1))
[  355.901488][    C3]  ? __init_waitqueue_head (./include/linux/list.h:45 (discriminator 2))
[  355.901491][    C3]  iterate_tty_write (drivers/tty/tty_io.c:1006)
[  355.901493][    C3]  ? tty_ldisc_ref_wait (drivers/tty/tty_ldisc.c:243)
[  355.901495][    C3]  file_tty_write.isra.0 (drivers/tty/tty_io.c:1081)
[  355.901497][    C3]  ? redirected_tty_write (./include/linux/file_ref.h:121 (discriminator 7))
[  355.901498][    C3]  new_sync_write (fs/read_write.c:595)
[  355.901500][    C3]  ? clockevents_program_event (kernel/time/clockevents.c:372)
[  355.901502][    C3]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  355.901503][    C3]  ? new_sync_read (./include/linux/ioprio.h:41)
[  355.901505][    C3]  ? generic_write_checks_count (fs/read_write.c:1754)
[  355.901508][    C3]  vfs_write (fs/read_write.c:688)
[  355.901510][    C3]  ? vfs_read (fs/read_write.c:574)
[  355.901511][    C3]  ksys_write (fs/read_write.c:740)
[  355.901512][    C3]  ? __ia32_sys_read (fs/read_write.c:724)
[  355.901514][    C3]  ? restore_fpregs_from_fpstate (arch/x86/kernel/fpu/xstate.h:242 arch/x86/kernel/fpu/core.c:207)
[  355.901517][    C3]  ? rcu_is_watching (./include/linux/context_tracking.h:128 (discriminator 3) kernel/rcu/tree.c:752 (discriminator 3))
[  355.901519][    C3]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[  355.901520][    C3]  ? irq_exit_rcu (kernel/softirq.c:754)
[  355.901521][    C3]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
[  355.901523][    C3] RIP: 0033:0x7ff15d73008e
[  355.901524][    C3] Code: 4d 89 d8 e8 94 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 03 ff ff ff 0f 1f 00 f3 0f 1e fa
All code
========
   0:	4d 89 d8             	mov    %r11,%r8
   3:	e8 94 bd 00 00       	call   0xbd9c
   8:	4c 8b 5d f8          	mov    -0x8(%rbp),%r11
   c:	41 8b 93 08 03 00 00 	mov    0x308(%r11),%edx
  13:	59                   	pop    %rcx
  14:	5e                   	pop    %rsi
  15:	48 83 f8 fc          	cmp    $0xfffffffffffffffc,%rax
  19:	74 11                	je     0x2c
  1b:	c9                   	leave
  1c:	c3                   	ret
  1d:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  24:	48 8b 45 10          	mov    0x10(%rbp),%rax
  28:	0f 05                	syscall
  2a:*	c9                   	leave		<-- trapping instruction
  2b:	c3                   	ret
  2c:	83 e2 39             	and    $0x39,%edx
  2f:	83 fa 08             	cmp    $0x8,%edx
  32:	75 e7                	jne    0x1b
  34:	e8 03 ff ff ff       	call   0xffffffffffffff3c
  39:	0f 1f 00             	nopl   (%rax)
  3c:	f3 0f 1e fa          	endbr64

Code starting with the faulting instruction
===========================================
   0:	c9                   	leave
   1:	c3                   	ret
   2:	83 e2 39             	and    $0x39,%edx
   5:	83 fa 08             	cmp    $0x8,%edx
   8:	75 e7                	jne    0xfffffffffffffff1
   a:	e8 03 ff ff ff       	call   0xffffffffffffff12
   f:	0f 1f 00             	nopl   (%rax)
  12:	f3 0f 1e fa          	endbr64
[  355.901525][    C3] RSP: 002b:00007ffecbc85030 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[  355.901527][    C3] RAX: ffffffffffffffda RBX: 000055fd26eab2c0 RCX: 00007ff15d73008e
[  355.901528][    C3] RDX: 0000000000000001 RSI: 000055fd26eab2c0 RDI: 0000000000000001
[  355.901529][    C3] RBP: 00007ffecbc85040 R08: 0000000000000000 R09: 0000000000000000
[  355.901529][    C3] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000001


Finger prints:
__mutex_lock:__tcf_chain_put:tcf_action_rcu_free:rcu_do_batch:rcu_core