======================================
| [ 34.890346][ C2] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) 
| [   34.890688][    C2]
| [   34.890783][    C2]
| [   34.890783][    C2] stack backtrace:
[   34.891298][    C2] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   34.891818][    C2] Call Trace:
[   34.891971][    C2]  <IRQ>
[ 34.892065][ C2] dump_stack_lvl (lib/dump_stack.c:117) 
[ 34.892258][ C2] print_irq_inversion_bug.part.0 (kernel/locking/lockdep.c:4024) 
[ 34.892497][ C2] ? __pfx_print_irq_inversion_bug.part.0 (kernel/locking/lockdep.c:4024) 
[ 34.892713][ C2] ? __pfx_usage_skip (kernel/locking/lockdep.c:2264) 
[ 34.892893][ C2] ? __pfx_usage_match (kernel/locking/lockdep.c:2256) 
[ 34.893171][ C2] ? arch_stack_walk (arch/x86/kernel/stacktrace.c:26) 
[ 34.893350][ C2] mark_lock_irq (kernel/locking/lockdep.c:4244) 
[ 34.893522][ C2] ? __pfx_mark_lock_irq (kernel/locking/lockdep.c:4207) 
[ 34.893700][ C2] ? stack_trace_save (kernel/stacktrace.c:123) 
[ 34.893876][ C2] ? add_chain_cache (kernel/locking/lockdep.c:3730) 
[ 34.894157][ C2] ? save_trace (kernel/locking/lockdep.c:586) 
[ 34.894336][ C2] mark_lock (kernel/locking/lockdep.c:4678) 
[ 34.894468][ C2] mark_usage (kernel/locking/lockdep.c:4567) 
[ 34.894600][ C2] __lock_acquire (kernel/locking/lockdep.c:5091) 
[ 34.894876][ C2] ? __lock_acquire (kernel/locking/lockdep.c:5137) 
[ 34.895053][ C2] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) 
[ 34.895266][ C2] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5756) 
[ 34.895444][ C2] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) 
[ 34.895764][ C2] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 34.895938][ C2] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 34.896112][ C2] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) 
[ 34.896335][ C2] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 34.896725][ C2] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) 
[ 34.896939][ C2] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 34.897123][ C2] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) 
[ 34.897337][ C2] br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) 
[ 34.897658][ C2] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) 
[ 34.897873][ C2] call_timer_fn (kernel/time/timer.c:1793) 
[ 34.898047][ C2] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1783) 
[ 34.898229][ C2] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1783) 
[ 34.898410][ C2] ? __pfx_call_timer_fn (kernel/time/timer.c:1770) 
[ 34.898582][ C2] ? mark_lock (kernel/locking/lockdep.c:4656 (discriminator 3)) 
[ 34.898716][ C2] __run_timers (kernel/time/timer.c:1845 kernel/time/timer.c:2418) 
[ 34.898884][ C2] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) 
[ 34.899204][ C2] ? __pfx___run_timers (kernel/time/timer.c:2389) 
[ 34.899388][ C2] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 34.899562][ C2] ? 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) 
[ 34.899736][ C2] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 34.900011][ C2] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 34.900188][ C2] ? timer_expire_remote (kernel/time/timer.c:2429 kernel/time/timer.c:2422 kernel/time/timer.c:2181) 
[ 34.900367][ C2] timer_expire_remote (kernel/time/timer.c:2430 kernel/time/timer.c:2422 kernel/time/timer.c:2181) 
[ 34.900539][ C2] tmigr_handle_remote_cpu (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:67 ./arch/x86/include/asm/irqflags.h:127 kernel/time/timer_migration.c:925) 
[ 34.900815][ C2] ? __pfx_tmigr_handle_remote_cpu (kernel/time/timer_migration.c:869) 
[ 34.901033][ C2] tmigr_handle_remote_up (kernel/time/timer_migration.c:1003) 
[ 34.901218][ C2] tmigr_handle_remote (kernel/time/timer_migration.c:488 kernel/time/timer_migration.c:1061) 
[ 34.901396][ C2] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1026) 
[ 34.901678][ C2] __do_softirq (kernel/softirq.c:554) 
[ 34.901854][ C2] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 34.901986][ C2] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[   34.902164][    C2]  </IRQ>
[   34.902255][    C2]  <TASK>
[ 34.902347][ C2] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 34.902663][ C2] RIP: 0010:_raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 34.902885][ C2] Code: 10 e8 41 10 94 fd 48 89 ef e8 79 80 94 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 e5 85 68 7b <74> 0e 5b 5d c3 cc cc cc cc e8 6f 7a b7 fd eb dc 0f 1f 44 00 00 5b
All code
========
   0:	10 e8                	adc    %ch,%al
   2:	41 10 94 fd 48 89 ef 	adc    %dl,-0x171076b8(%r13,%rdi,8)
   9:	e8 
   a:	79 80                	jns    0xffffffffffffff8c
   c:	94                   	xchg   %eax,%esp
   d:	fd                   	std
   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 e5 85 68 7b 	decl   %gs:0x7b6885e5(%rip)        # 0x7b68860f
  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 6f 7a b7 fd       	call   0xfffffffffdb77aa7
  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 6f 7a b7 fd       	call   0xfffffffffdb77a7d
   e:	eb dc                	jmp    0xffffffffffffffec
  10:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  15:	5b                   	pop    %rbx
[   34.903601][    C2] RSP: 0018:ffffc9000116f3e0 EFLAGS: 00000282
[   34.903820][    C2] RAX: 0000000000000006 RBX: 0000000000000200 RCX: 1ffffffff0ca6f61
[   34.904077][    C2] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff849b41f1
[   34.904445][    C2] RBP: ffff888001041080 R08: 0000000000000001 R09: fffffbfff0ca77e2
[   34.904703][    C2] R10: ffffffff8653bf17 R11: 0000000000001000 R12: ffff888001041080
[   34.905064][    C2] R13: ffffea0000187200 R14: ffff8880010433c0 R15: ffff8880061cc000
[ 34.905332][ C2] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 34.905547][ C2] get_partial_node.part.0 (mm/slub.c:2623) 
[ 34.905721][ C2] ___slab_alloc (mm/slub.c:2583 mm/slub.c:2701 mm/slub.c:3505) 
[ 34.905996][ C2] ? fs_reclaim_acquire (mm/page_alloc.c:3715 mm/page_alloc.c:3706) 
[ 34.906169][ C2] ? p9_fcall_init (net/9p/client.c:232) 
[ 34.906348][ C2] ? __pfx___lock_release (kernel/locking/lockdep.c:5406) 
[ 34.906527][ C2] ? p9_fcall_init (net/9p/client.c:232) 
[ 34.906803][ C2] ? __kmalloc (mm/slub.c:3610 mm/slub.c:3663 mm/slub.c:3835 mm/slub.c:3965 mm/slub.c:3979) 
[ 34.906978][ C2] __kmalloc (mm/slub.c:3610 mm/slub.c:3663 mm/slub.c:3835 mm/slub.c:3965 mm/slub.c:3979) 
[ 34.907120][ C2] p9_fcall_init (net/9p/client.c:232) 
[ 34.907293][ C2] p9_tag_alloc (net/9p/client.c:297) 
[ 34.907466][ C2] ? __pfx_p9_tag_alloc (net/9p/client.c:277) 
[ 34.907742][ C2] ? validate_chain (./include/linux/hash.h:78 kernel/locking/lockdep.c:3759 kernel/locking/lockdep.c:3782 kernel/locking/lockdep.c:3837) 
[ 34.907917][ C2] ? 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) 
[ 34.908093][ C2] p9_client_prepare_req (net/9p/client.c:641) 
[ 34.908268][ C2] ? 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) 
[ 34.908546][ C2] ? __pfx_p9_client_prepare_req (net/9p/client.c:625) 
[ 34.908764][ C2] ? __lock_acquire (kernel/locking/lockdep.c:5137) 
[ 34.908937][ C2] p9_client_rpc (net/9p/client.c:688 (discriminator 4)) 
[ 34.909110][ C2] ? __pfx_p9_client_rpc (net/9p/client.c:672) 
[ 34.909283][ C2] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 34.909460][ C2] ? list_lru_add (mm/list_lru.c:106) 
[ 34.909634][ C2] ? __pfx___lock_release (kernel/locking/lockdep.c:5406) 
[ 34.909808][ C2] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 34.910186][ C2] ? find_held_lock (kernel/locking/lockdep.c:5244) 
[ 34.910361][ C2] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 34.910531][ C2] ? __pfx___lock_release (kernel/locking/lockdep.c:5406) 
[ 34.910704][ C2] p9_client_clunk (net/9p/client.c:1438 (discriminator 3)) 
[ 34.910981][ C2] v9fs_dentry_release (fs/9p/vfs_dentry.c:54) 
[ 34.911154][ C2] __dentry_kill (fs/dcache.c:608) 
[ 34.911330][ C2] ? __pfx_kfree_link (fs/libfs.c:1573) 
[ 34.911506][ C2] dput.part.0 (fs/dcache.c:845) 
[ 34.911677][ C2] walk_component (fs/namei.c:562 fs/namei.c:1027 fs/namei.c:2009) 
[ 34.911952][ C2] link_path_walk.part.0.constprop.0 (fs/namei.c:2328) 
[ 34.912171][ C2] ? __pfx_link_path_walk.part.0.constprop.0 (fs/namei.c:2249) 
[ 34.912389][ C2] ? validate_chain (./include/linux/hash.h:78 kernel/locking/lockdep.c:3759 kernel/locking/lockdep.c:3782 kernel/locking/lockdep.c:3837) 
[ 34.912662][ C2] ? 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) 
[ 34.912838][ C2] path_lookupat (fs/namei.c:2254 (discriminator 2) fs/namei.c:2484 (discriminator 2)) 
[ 34.913012][ C2] filename_lookup (fs/namei.c:2514) 
[ 34.913186][ C2] ? __pfx_filename_lookup (fs/namei.c:2508) 
[ 34.913368][ C2] ? __pfx_kfree_link (fs/libfs.c:1573) 
[ 34.913646][ C2] ? find_held_lock (kernel/locking/lockdep.c:5244) 
[ 34.913820][ C2] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 34.913992][ C2] ? __might_fault (mm/memory.c:6216 mm/memory.c:6209) 
[ 34.914170][ C2] ? __pfx___lock_release (kernel/locking/lockdep.c:5406) 
[ 34.914350][ C2] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 34.914528][ C2] vfs_statx (fs/stat.c:244) 
[ 34.914660][ C2] ? __pfx_vfs_statx (fs/stat.c:234) 
[ 34.914834][ C2] ? getname_flags (./arch/x86/include/asm/atomic.h:28 ./include/linux/atomic/atomic-arch-fallback.h:503 ./include/linux/atomic/atomic-instrumented.h:68 fs/namei.c:190) 
[ 34.915113][ C2] vfs_fstatat (fs/stat.c:305) 
[ 34.915248][ C2] __do_sys_newfstatat (fs/stat.c:469) 
[ 34.915418][ C2] ? __pfx___do_sys_newfstatat (fs/stat.c:464) 
[ 34.915595][ C2] ? __x64_sys_openat (fs/open.c:1432) 
[ 34.915768][ C2] ? __pfx___x64_sys_openat (fs/open.c:1432) 
[ 34.916043][ C2] ? __pfx_do_faccessat (fs/open.c:465) 
[ 34.916223][ C2] ? lockdep_hardirqs_on_prepare.part.0 (kernel/locking/lockdep.c:4300 kernel/locking/lockdep.c:4359) 
[ 34.916439][ C2] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 34.916614][ C2] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) 
[   34.916934][    C2] RIP: 0033:0x7fc9a2f63eae
[ 34.917128][ C2] Code: 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 07 00 00 00 0f 1f 80 00 00 00 00 f3 0f 1e fa 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 0b 31 c0 c3 0f 1f 84 00 00 00 00 00 f7 d8 89 05
All code
========
   0:	48 89 f2             	mov    %rsi,%rdx
   3:	b9 00 01 00 00       	mov    $0x100,%ecx
   8:	48 89 fe             	mov    %rdi,%rsi
   b:	bf 9c ff ff ff       	mov    $0xffffff9c,%edi
  10:	e9 07 00 00 00       	jmp    0x1c
  15:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  1c:	f3 0f 1e fa          	endbr64
  20:	41 89 ca             	mov    %ecx,%r10d
  23:	b8 06 01 00 00       	mov    $0x106,%eax
  28:	0f 05                	syscall
  2a:*	3d 00 f0 ff ff       	cmp    $0xfffff000,%eax		<-- trapping instruction
  2f:	77 0b                	ja     0x3c
  31:	31 c0                	xor    %eax,%eax
  33:	c3                   	ret
  34:	0f 1f 84 00 00 00 00 	nopl   0x0(%rax,%rax,1)
  3b:	00 
  3c:	f7 d8                	neg    %eax
  3e:	89                   	.byte 0x89
  3f:	05                   	.byte 0x5

Code starting with the faulting instruction
===========================================
   0:	3d 00 f0 ff ff       	cmp    $0xfffff000,%eax
   5:	77 0b                	ja     0x12
   7:	31 c0                	xor    %eax,%eax
   9:	c3                   	ret
   a:	0f 1f 84 00 00 00 00 	nopl   0x0(%rax,%rax,1)
  11:	00 
  12:	f7 d8                	neg    %eax
  14:	89                   	.byte 0x89
  15:	05                   	.byte 0x5
[   34.917855][    C2] RSP: 002b:00007ffdb9fc9f88 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
[   34.918116][    C2] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fc9a2f63eae
[   34.918389][    C2] RDX: 00007ffdb9fca060 RSI: 00007ffdb9fc9f90 RDI: 00000000ffffff9c
[   34.918751][    C2] RBP: 00007ffdb9fca120 R08: 00000000ffffffff R09: 00007ffdb9fc9f90
[   34.919007][    C2] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdb9fc9f97


Finger prints:
dump_stack_lvl:mark_lock_irq:mark_lock:mark_usage