======================================
| [ 43.866706][ C2] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) 
| [   43.866926][    C2]
| [   43.867021][    C2]
| [   43.867021][    C2] stack backtrace:
[   43.867615][    C2] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   43.868229][    C2] Call Trace:
[   43.868363][    C2]  <IRQ>
[ 43.868457][ C2] dump_stack_lvl (lib/dump_stack.c:117) 
[ 43.868636][ C2] print_irq_inversion_bug.part.0 (kernel/locking/lockdep.c:4024) 
[ 43.868863][ C2] ? __pfx_print_irq_inversion_bug.part.0 (kernel/locking/lockdep.c:4024) 
[ 43.869197][ C2] ? __pfx_usage_skip (kernel/locking/lockdep.c:2264) 
[ 43.869373][ C2] ? __pfx_usage_match (kernel/locking/lockdep.c:2256) 
[ 43.869548][ C2] ? arch_stack_walk (arch/x86/kernel/stacktrace.c:26) 
[ 43.869724][ C2] mark_lock_irq (kernel/locking/lockdep.c:4244) 
[ 43.870005][ C2] ? __pfx_mark_lock_irq (kernel/locking/lockdep.c:4207) 
[ 43.870183][ C2] ? stack_trace_save (kernel/stacktrace.c:123) 
[ 43.870358][ C2] ? add_chain_cache (kernel/locking/lockdep.c:3730) 
[ 43.870552][ C2] ? save_trace (kernel/locking/lockdep.c:586) 
[ 43.870727][ C2] mark_lock (kernel/locking/lockdep.c:4678) 
[ 43.870854][ C2] mark_usage (kernel/locking/lockdep.c:4567) 
[ 43.870988][ C2] __lock_acquire (kernel/locking/lockdep.c:5091) 
[ 43.871165][ C2] ? __lock_acquire (kernel/locking/lockdep.c:5137) 
[ 43.871343][ C2] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) bridge
[ 43.871756][ C2] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5756) 
[ 43.871933][ C2] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 43.872200][ C2] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5719) 
[ 43.872487][ C2] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 43.872666][ C2] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 43.872924][ C2] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 43.873097][ C2] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 43.873479][ C2] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 43.873657][ C2] ? br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 43.873916][ C2] br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:87) bridge
[ 43.874174][ C2] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) bridge
[ 43.874582][ C2] call_timer_fn (kernel/time/timer.c:1793) 
[ 43.874758][ C2] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1783) 
[ 43.874931][ C2] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1783) 
[ 43.875105][ C2] ? __pfx_call_timer_fn (kernel/time/timer.c:1770) 
[ 43.875388][ C2] ? mark_lock (kernel/locking/lockdep.c:4656 (discriminator 3)) 
[ 43.875529][ C2] __run_timers (kernel/time/timer.c:1845 kernel/time/timer.c:2418) 
[ 43.875703][ C2] ? __pfx_br_forward_delay_timer_expired (net/bridge/br_stp_timer.c:80) bridge
[ 43.875988][ C2] ? __pfx___run_timers (kernel/time/timer.c:2389) 
[ 43.876270][ C2] ? __lock_release (kernel/locking/lockdep.c:5430) 
[ 43.876444][ 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) 
[ 43.876621][ C2] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 43.876796][ C2] ? lock_acquire (kernel/locking/lockdep.c:5727) 
[ 43.877080][ C2] ? timer_expire_remote (kernel/time/timer.c:2429 kernel/time/timer.c:2422 kernel/time/timer.c:2181) 
[ 43.877261][ C2] timer_expire_remote (kernel/time/timer.c:2430 kernel/time/timer.c:2422 kernel/time/timer.c:2181) 
[ 43.877439][ 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) 
[ 43.877630][ C2] ? __pfx_tmigr_handle_remote_cpu (kernel/time/timer_migration.c:869) 
[ 43.877970][ C2] tmigr_handle_remote_up (kernel/time/timer_migration.c:1003) 
[ 43.878148][ C2] tmigr_handle_remote (kernel/time/timer_migration.c:488 kernel/time/timer_migration.c:1061) 
[ 43.878324][ C2] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1026) 
[ 43.878500][ C2] __do_softirq (kernel/softirq.c:554) 
[ 43.878679][ C2] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) 
[ 43.878816][ C2] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) 
[   43.878988][    C2]  </IRQ>
[   43.879073][    C2]  <TASK>
[ 43.879163][ C2] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 43.879487][ C2] RIP: 0010:kasan_report (mm/kasan/report.c:93 mm/kasan/report.c:585) 
[ 43.879666][ C2] Code: 90 90 66 0f 1f 00 41 57 41 56 41 55 41 54 55 53 48 83 ec 70 9c 8f 04 24 0f 01 ca 65 4c 8b 3d 2f 7c cb 7b 41 8b 87 a8 14 00 00 <85> c0 0f 85 b7 00 00 00 48 89 fd 49 89 f6 89 d3 49 89 cd e8 f0 f6
All code
========
   0:	90                   	nop
   1:	90                   	nop
   2:	66 0f 1f 00          	nopw   (%rax)
   6:	41 57                	push   %r15
   8:	41 56                	push   %r14
   a:	41 55                	push   %r13
   c:	41 54                	push   %r12
   e:	55                   	push   %rbp
   f:	53                   	push   %rbx
  10:	48 83 ec 70          	sub    $0x70,%rsp
  14:	9c                   	pushf
  15:	8f 04 24             	pop    (%rsp)
  18:	0f 01 ca             	clac
  1b:	65 4c 8b 3d 2f 7c cb 	mov    %gs:0x7bcb7c2f(%rip),%r15        # 0x7bcb7c52
  22:	7b 
  23:	41 8b 87 a8 14 00 00 	mov    0x14a8(%r15),%eax
  2a:*	85 c0                	test   %eax,%eax		<-- trapping instruction
  2c:	0f 85 b7 00 00 00    	jne    0xe9
  32:	48 89 fd             	mov    %rdi,%rbp
  35:	49 89 f6             	mov    %rsi,%r14
  38:	89 d3                	mov    %edx,%ebx
  3a:	49 89 cd             	mov    %rcx,%r13
  3d:	e8                   	.byte 0xe8
  3e:	f0                   	lock
  3f:	f6                   	.byte 0xf6

Code starting with the faulting instruction
===========================================
   0:	85 c0                	test   %eax,%eax
   2:	0f 85 b7 00 00 00    	jne    0xbf
   8:	48 89 fd             	mov    %rdi,%rbp
   b:	49 89 f6             	mov    %rsi,%r14
   e:	89 d3                	mov    %edx,%ebx
  10:	49 89 cd             	mov    %rcx,%r13
  13:	e8                   	.byte 0xe8
  14:	f0                   	lock
  15:	f6                   	.byte 0xf6
[   43.880405][    C2] RSP: 0018:ffffc9000090f208 EFLAGS: 00000282
[   43.880631][    C2] RAX: 00000000ffffffff RBX: ffff888009995950 RCX: ffffffff8623b764
[   43.880892][    C2] RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888009995950
[   43.881262][    C2] RBP: 0000000000001f98 R08: ffff888009994064 R09: 000000000000005a
[   43.881530][    C2] R10: 0000000000000008 R11: 0000000000002000 R12: 5a5a5a5a5a5a5a5a
[   43.881812][    C2] R13: 000000000000005a R14: dffffc0000000000 R15: ffff8880057d45c0
[ 43.882298][ C2] ? memchr_inv (lib/string.c:856) 
[ 43.882481][ C2] ? __alloc_pages (mm/page_alloc.c:4541) 
[ 43.882662][ C2] memchr_inv (lib/string.c:856) 
[ 43.882794][ C2] check_bytes_and_report (mm/slub.c:1175) 
[ 43.883068][ C2] check_object (mm/slub.c:853 mm/slub.c:1353) 
[ 43.883248][ C2] alloc_debug_processing (mm/slub.c:1544 mm/slub.c:1554) 
[ 43.883438][ C2] ___slab_alloc (mm/slub.c:2537 mm/slub.c:3536) 
[ 43.883617][ C2] ? fs_reclaim_acquire (mm/page_alloc.c:3715 mm/page_alloc.c:3706) 
[ 43.883797][ C2] ? p9_fcall_init (net/9p/client.c:232) 
[ 43.884089][ C2] ? p9_fcall_init (net/9p/client.c:232) 
[ 43.884263][ C2] ? __kmalloc (mm/slub.c:3610 mm/slub.c:3663 mm/slub.c:3835 mm/slub.c:3965 mm/slub.c:3979) 
[ 43.884436][ C2] __kmalloc (mm/slub.c:3610 mm/slub.c:3663 mm/slub.c:3835 mm/slub.c:3965 mm/slub.c:3979) 
[ 43.884572][ C2] p9_fcall_init (net/9p/client.c:232) 
[ 43.884859][ C2] p9_tag_alloc (net/9p/client.c:297) 
[ 43.885044][ C2] ? __pfx_p9_tag_alloc (net/9p/client.c:277) 
[ 43.885227][ C2] ? mark_lock (kernel/locking/lockdep.c:4656 (discriminator 3)) 
[ 43.885361][ C2] ? __lock_acquire (kernel/locking/lockdep.c:5137) 
[ 43.885542][ C2] p9_client_prepare_req (net/9p/client.c:641) 
[ 43.885720][ C2] ? __pfx_p9_client_prepare_req (net/9p/client.c:625) 
[ 43.885931][ C2] ? find_held_lock (kernel/locking/lockdep.c:5244) 
[ 43.886112][ C2] p9_client_rpc (net/9p/client.c:688 (discriminator 4)) 
[ 43.886290][ 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) 
[ 43.886577][ C2] ? __pfx_p9_client_rpc (net/9p/client.c:672) 
[ 43.886762][ C2] ? v9fs_fid_find (fs/9p/fid.c:114) 
[ 43.886942][ C2] ? 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) 
[ 43.887119][ C2] ? _raw_spin_unlock (./arch/x86/include/asm/preempt.h:94 ./include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:186) 
[ 43.887406][ C2] ? __pfx_v9fs_fid_find (fs/9p/fid.c:114) 
[ 43.887586][ C2] ? __pfx_make_vfsgid (fs/mnt_idmapping.c:110) 
[ 43.887765][ C2] ? v9fs_fid_add (fs/9p/fid.c:41) 
[ 43.887946][ C2] p9_client_readlink (net/9p/client.c:2238) 
[ 43.888232][ C2] v9fs_vfs_get_link_dotl (fs/9p/vfs_inode_dotl.c:822 fs/9p/vfs_inode_dotl.c:806) 
[ 43.888412][ C2] ? __pfx_v9fs_vfs_get_link_dotl (fs/9p/vfs_inode_dotl.c:809) 
[ 43.888641][ C2] ? __lookup_slow (fs/namei.c:1692) 
[ 43.888822][ C2] pick_link (fs/namei.c:1808) 
[ 43.889064][ C2] ? find_held_lock (kernel/locking/lockdep.c:5244) 
[ 43.889242][ C2] step_into (fs/namei.c:1874) 
[ 43.889377][ C2] ? __up_read (./arch/x86/include/asm/atomic64_64.h:79 ./include/linux/atomic/atomic-arch-fallback.h:2749 ./include/linux/atomic/atomic-long.h:184 ./include/linux/atomic/atomic-instrumented.h:3317 kernel/locking/rwsem.c:1347) 
[ 43.889554][ C2] ? __pfx_step_into (fs/namei.c:1839) 
[ 43.889731][ C2] ? walk_component (fs/namei.c:2005) 
[ 43.890019][ C2] link_path_walk.part.0.constprop.0 (fs/namei.c:2331) 
[ 43.890245][ C2] ? __pfx_link_path_walk.part.0.constprop.0 (fs/namei.c:2249) 
[ 43.890468][ C2] path_openat (fs/namei.c:3795) 
[ 43.890646][ C2] ? __pfx_path_openat (fs/namei.c:3781) 
[ 43.890823][ C2] ? __lock_acquire (kernel/locking/lockdep.c:5137) 
[ 43.891003][ C2] do_filp_open (fs/namei.c:3826) 
[ 43.891178][ C2] ? __pfx_do_filp_open (fs/namei.c:3820) 
[ 43.891355][ C2] ? find_held_lock (kernel/locking/lockdep.c:5244) 
[ 43.891645][ C2] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 43.891821][ C2] ? alloc_fd (fs/file.c:555 (discriminator 10)) 
[ 43.891961][ C2] ? 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) 
[ 43.892140][ C2] ? _raw_spin_unlock (./arch/x86/include/asm/preempt.h:94 ./include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:186) 
[ 43.892423][ C2] ? alloc_fd (fs/file.c:555 (discriminator 10)) 
[ 43.892560][ C2] do_sys_openat2 (fs/open.c:1406) 
[ 43.892737][ C2] ? vfs_fstatat (fs/stat.c:308) 
[ 43.892915][ C2] ? __pfx_do_sys_openat2 (fs/open.c:1392) 
[ 43.893091][ C2] ? __pfx___do_sys_newfstatat (fs/stat.c:464) 
[ 43.893379][ C2] __x64_sys_openat (fs/open.c:1432) 
[ 43.893613][ C2] ? __pfx___x64_sys_openat (fs/open.c:1432) 
[ 43.893791][ C2] ? __pfx_do_faccessat (fs/open.c:465) 
[ 43.893971][ C2] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 43.894256][ C2] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) 
[   43.894475][    C2] RIP: 0033:0x7f83f73090e8
[ 43.894657][ C2] Code: f9 41 89 f0 41 83 e2 40 75 30 89 f0 25 00 00 41 00 3d 00 00 41 00 74 22 44 89 c2 4c 89 ce bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 30 c3 0f 1f 80 00 00 00 00 48 8d 44 24 08 c7
All code
========
   0:	f9                   	stc
   1:	41 89 f0             	mov    %esi,%r8d
   4:	41 83 e2 40          	and    $0x40,%r10d
   8:	75 30                	jne    0x3a
   a:	89 f0                	mov    %esi,%eax
   c:	25 00 00 41 00       	and    $0x410000,%eax
  11:	3d 00 00 41 00       	cmp    $0x410000,%eax
  16:	74 22                	je     0x3a
  18:	44 89 c2             	mov    %r8d,%edx
  1b:	4c 89 ce             	mov    %r9,%rsi
  1e:	bf 9c ff ff ff       	mov    $0xffffff9c,%edi
  23:	b8 01 01 00 00       	mov    $0x101,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 30                	ja     0x62
  32:	c3                   	ret
  33:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  3a:	48 8d 44 24 08       	lea    0x8(%rsp),%rax
  3f:	c7                   	.byte 0xc7

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 30                	ja     0x38
   8:	c3                   	ret
   9:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  10:	48 8d 44 24 08       	lea    0x8(%rsp),%rax
  15:	c7                   	.byte 0xc7
[   43.895396][    C2] RSP: 002b:00007fff2cb09b38 EFLAGS: 00000287 ORIG_RAX: 0000000000000101
[   43.895663][    C2] RAX: ffffffffffffffda RBX: 00007fff2cb09dcf RCX: 00007f83f73090e8
[   43.896142][    C2] RDX: 0000000000080000 RSI: 00007fff2cb09bb0 RDI: 00000000ffffff9c
[   43.896412][    C2] RBP: 00007fff2cb09ba0 R08: 0000000000080000 R09: 00007fff2cb09bb0
[   43.896689][    C2] R10: 0000000000000000 R11: 0000000000000287 R12: 00007fff2cb09bb7


Finger prints:
dump_stack_lvl:mark_lock_irq:mark_lock:mark_usage