======================================
| [ 46.442661][ C1] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) 
| [   46.442882][    C1]
| [   46.442970][    C1]
| [   46.442970][    C1] stack backtrace:
[   46.443455][    C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   46.443953][    C1] Call Trace:
[   46.444093][    C1]  <IRQ>
[ 46.444183][ C1] dump_stack_lvl (lib/dump_stack.c:117) 
[ 46.444370][ C1] print_irq_inversion_bug.part.0 (kernel/locking/lockdep.c:4024) 
[ 46.444686][ C1] ? __pfx_print_irq_inversion_bug.part.0 (kernel/locking/lockdep.c:4024) 
[ 46.444902][ C1] ? __pfx_usage_skip (kernel/locking/lockdep.c:2264) 
[ 46.445074][ C1] ? __pfx_usage_match (kernel/locking/lockdep.c:2256) 
[ 46.445247][ C1] ? arch_stack_walk (arch/x86/kernel/stacktrace.c:26) 
[ 46.445516][ C1] mark_lock_irq (kernel/locking/lockdep.c:4244) 
[ 46.445691][ C1] ? __pfx_mark_lock_irq (kernel/locking/lockdep.c:4207) 
[ 46.445870][ C1] ? stack_trace_save (kernel/stacktrace.c:123) 
[ 46.446044][ C1] ? add_chain_cache (kernel/locking/lockdep.c:3730) 
[ 46.446314][ C1] ? save_trace (kernel/locking/lockdep.c:586) 
[ 46.446488][ C1] mark_lock (kernel/locking/lockdep.c:4678) 
[ 46.446620][ C1] mark_usage (kernel/locking/lockdep.c:4567) 
[ 46.446752][ C1] __lock_acquire (kernel/locking/lockdep.c:5091) 
[ 46.446927][ C1] ? __lock_acquire (kernel/locking/lockdep.c:5137) 
[ 46.447200][ C1] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) bridge
[ 46.447501][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5756) 
[ 46.447673][ C1] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 46.447928][ C1] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 46.448103][ C1] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 46.448278][ C1] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 46.448531][ C1] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 46.448802][ C1] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 46.449071][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 46.449246][ C1] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 46.449502][ C1] br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 46.449857][ C1] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) bridge
[ 46.450158][ C1] call_timer_fn (kernel/time/timer.c:1793) 
[ 46.450340][ C1] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1783) 
[ 46.450612][ C1] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1783) 
[ 46.450799][ C1] ? __pfx_call_timer_fn (kernel/time/timer.c:1770) 
[ 46.450977][ C1] ? mark_lock (kernel/locking/lockdep.c:4656 (discriminator 3)) 
[ 46.451115][ C1] __run_timers (kernel/time/timer.c:1845 kernel/time/timer.c:2418) 
[ 46.451293][ C1] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) bridge
[ 46.451692][ C1] ? __pfx___run_timers (kernel/time/timer.c:2389) 
[ 46.451868][ C1] ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:115 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116) 
[ 46.452044][ C1] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 46.452223][ C1] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 46.452505][ C1] ? run_timer_softirq (kernel/time/timer.c:2429 kernel/time/timer.c:2422 kernel/time/timer.c:2438 kernel/time/timer.c:2448) 
[ 46.452682][ C1] run_timer_softirq (kernel/time/timer.c:2430 kernel/time/timer.c:2422 kernel/time/timer.c:2438 kernel/time/timer.c:2448) 
[ 46.452858][ C1] __do_softirq (kernel/softirq.c:554) 
[ 46.453037][ C1] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 46.453265][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[   46.453444][    C1]  </IRQ>
[   46.453535][    C1]  <TASK>
[ 46.453625][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 46.453840][ C1] RIP: 0010:_raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 46.454179][ C1] Code: 10 e8 21 49 9b fd 48 89 ef e8 59 b9 9b fd 81 e3 00 02 00 00 75 1d 9c 58 f6 c4 02 75 29 48 85 db 74 01 fb 65 ff 0d 05 bf 8f 56 <74> 0e 5b 5d c3 cc cc cc cc e8 4f b3 be fd eb dc 0f 1f 44 00 00 5b
All code
========
   0:	10 e8                	adc    %ch,%al
   2:	21 49 9b             	and    %ecx,-0x65(%rcx)
   5:	fd                   	std
   6:	48 89 ef             	mov    %rbp,%rdi
   9:	e8 59 b9 9b fd       	call   0xfffffffffd9bb967
   e:	81 e3 00 02 00 00    	and    $0x200,%ebx
  14:	75 1d                	jne    0x33
  16:	9c                   	pushf
  17:	58                   	pop    %rax
  18:	f6 c4 02             	test   $0x2,%ah
  1b:	75 29                	jne    0x46
  1d:	48 85 db             	test   %rbx,%rbx
  20:	74 01                	je     0x23
  22:	fb                   	sti
  23:	65 ff 0d 05 bf 8f 56 	decl   %gs:0x568fbf05(%rip)        # 0x568fbf2f
  2a:*	74 0e                	je     0x3a		<-- trapping instruction
  2c:	5b                   	pop    %rbx
  2d:	5d                   	pop    %rbp
  2e:	c3                   	ret
  2f:	cc                   	int3
  30:	cc                   	int3
  31:	cc                   	int3
  32:	cc                   	int3
  33:	e8 4f b3 be fd       	call   0xfffffffffdbeb387
  38:	eb dc                	jmp    0x16
  3a:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  3f:	5b                   	pop    %rbx

Code starting with the faulting instruction
===========================================
   0:	74 0e                	je     0x10
   2:	5b                   	pop    %rbx
   3:	5d                   	pop    %rbp
   4:	c3                   	ret
   5:	cc                   	int3
   6:	cc                   	int3
   7:	cc                   	int3
   8:	cc                   	int3
   9:	e8 4f b3 be fd       	call   0xfffffffffdbeb35d
   e:	eb dc                	jmp    0xffffffffffffffec
  10:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  15:	5b                   	pop    %rbx
[   46.454804][    C1] RSP: 0018:ffffc90000bcf7a0 EFLAGS: 00000282
[   46.455132][    C1] RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff5664179
[   46.455399][    C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffa9740911
[   46.455675][    C1] RBP: ffff888001041080 R08: 0000000000000001 R09: fffffbfff56649fa
[   46.456039][    C1] R10: ffffffffab324fd7 R11: 0000000000001000 R12: ffff888001041080
[   46.456307][    C1] R13: ffffea0000199600 R14: ffff8880010433c0 R15: ffff88800665c000
[ 46.456676][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 46.456897][ C1] get_partial_node.part.0 (mm/slub.c:2623) 
[ 46.457083][ C1] ___slab_alloc (mm/slub.c:2583 mm/slub.c:2701 mm/slub.c:3505) 
[ 46.457260][ C1] ? fs_reclaim_acquire (mm/page_alloc.c:3715 mm/page_alloc.c:3706) 
[ 46.457531][ C1] ? p9_fcall_init (net/9p/client.c:232) 
[ 46.457709][ C1] ? __pfx___lock_release (kernel/locking/lockdep.c:5406) 
[ 46.457888][ C1] ? p9_fcall_init (net/9p/client.c:232) 
[ 46.458065][ C1] ? __kmalloc (mm/slub.c:3610 mm/slub.c:3663 mm/slub.c:3835 mm/slub.c:3965 mm/slub.c:3979) 
[ 46.458243][ C1] __kmalloc (mm/slub.c:3610 mm/slub.c:3663 mm/slub.c:3835 mm/slub.c:3965 mm/slub.c:3979) 
[ 46.458471][ C1] p9_fcall_init (net/9p/client.c:232) 
[ 46.458649][ C1] p9_tag_alloc (net/9p/client.c:295) 
[ 46.458834][ C1] ? __pfx_p9_tag_alloc (net/9p/client.c:277) 
[ 46.459011][ C1] p9_client_prepare_req (net/9p/client.c:641) 
[ 46.459281][ C1] ? __pfx_p9_client_prepare_req (net/9p/client.c:625) 
[ 46.459497][ C1] ? stack_depot_save_flags (lib/stackdepot.c:609) 
[ 46.459675][ C1] ? __pfx_validate_chain (kernel/locking/lockdep.c:3825) 
[ 46.459851][ C1] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:228) 
[ 46.460122][ C1] ? mark_lock (kernel/locking/lockdep.c:4656 (discriminator 3)) 
[ 46.460257][ C1] p9_client_rpc (net/9p/client.c:688 (discriminator 4)) 
[ 46.460438][ C1] ? __pfx_p9_client_rpc (net/9p/client.c:672) 
[ 46.460615][ C1] ? mark_lock (kernel/locking/lockdep.c:4656 (discriminator 3)) 
[ 46.460749][ C1] ? find_held_lock (kernel/locking/lockdep.c:5244) 
[ 46.461021][ C1] ? v9fs_dir_release (./include/net/9p/client.h:269 fs/9p/vfs_dir.c:224) 
[ 46.461198][ C1] ? __pfx___lock_release (kernel/locking/lockdep.c:5406) 
[ 46.461375][ C1] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 46.461551][ C1] ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:115 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116) 
[ 46.461730][ C1] p9_client_clunk (net/9p/client.c:1438 (discriminator 3)) 
[ 46.461916][ C1] v9fs_dir_release (./include/net/9p/client.h:278 fs/9p/vfs_dir.c:224) 
[ 46.462093][ C1] __fput (fs/file_table.c:422) 
[ 46.462230][ C1] task_work_run (kernel/task_work.c:180 (discriminator 1)) 
[ 46.462409][ C1] ? __pfx_task_work_run (kernel/task_work.c:148) 
[ 46.462684][ C1] ? switch_task_namespaces (kernel/nsproxy.c:250) 
[ 46.462861][ 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) 
[ 46.463038][ C1] do_exit (kernel/exit.c:879) 
[ 46.463173][ C1] ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:115 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116) 
[ 46.463447][ C1] ? __pfx_do_exit (kernel/exit.c:819) 
[ 46.463628][ C1] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 46.463805][ C1] do_group_exit (kernel/exit.c:1008) 
[ 46.463996][ C1] __x64_sys_exit_group (kernel/exit.c:1036) 
[ 46.464265][ C1] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 46.464446][ C1] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) 
[   46.464666][    C1] RIP: 0033:0x7f6d926f8a8d
[ 46.464849][ C1] Code: Unable to access opcode bytes at 0x7f6d926f8a63.

Code starting with the faulting instruction
===========================================
[   46.465178][    C1] RSP: 002b:00007fffe1e3c048 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
[   46.465451][    C1] RAX: ffffffffffffffda RBX: 00007f6d927d59c0 RCX: 00007f6d926f8a8d
[   46.465715][    C1] RDX: 00000000000000e7 RSI: fffffffffffffe90 RDI: 0000000000000000
[   46.466092][    C1] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000058
[   46.466362][    C1] R10: 00007fffe1e3be70 R11: 0000000000000246 R12: 00007f6d927d59c0


Finger prints:
dump_stack_lvl:mark_lock_irq:mark_lock:mark_usage