======================================
| [ 1170.346811][    C1] page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0)
| [ 1170.347116][    C1] ------------[ cut here ]------------
| [ 1170.347275][    C1] kernel BUG at include/linux/mm.h:1140!
| [ 1170.347486][    C1] Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
[ 1170.347913][    C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 1170.348246][ C1] RIP: 0010:__free_pages (./include/linux/mm.h:1140 ./include/linux/mm.h:1138 mm/page_alloc.c:4819) 
[ 1170.348397][ C1] Code: 0f 94 c3 e9 ba fe ff ff 48 c7 c6 a0 18 38 ba 4c 89 e7 e8 df bf f4 ff 90 0f 0b 48 c7 c6 40 29 38 ba 4c 89 e7 e8 cd bf f4 ff 90 <0f> 0b 48 89 ef e8 72 03 09 00 e9 c5 fe ff ff e8 98 03 09 00 e9 35
All code
========
   0:	0f 94 c3             	sete   %bl
   3:	e9 ba fe ff ff       	jmp    0xfffffffffffffec2
   8:	48 c7 c6 a0 18 38 ba 	mov    $0xffffffffba3818a0,%rsi
   f:	4c 89 e7             	mov    %r12,%rdi
  12:	e8 df bf f4 ff       	call   0xfffffffffff4bff6
  17:	90                   	nop
  18:	0f 0b                	ud2
  1a:	48 c7 c6 40 29 38 ba 	mov    $0xffffffffba382940,%rsi
  21:	4c 89 e7             	mov    %r12,%rdi
  24:	e8 cd bf f4 ff       	call   0xfffffffffff4bff6
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	48 89 ef             	mov    %rbp,%rdi
  2f:	e8 72 03 09 00       	call   0x903a6
  34:	e9 c5 fe ff ff       	jmp    0xfffffffffffffefe
  39:	e8 98 03 09 00       	call   0x903d6
  3e:	e9                   	.byte 0xe9
  3f:	35                   	.byte 0x35

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	48 89 ef             	mov    %rbp,%rdi
   5:	e8 72 03 09 00       	call   0x9037c
   a:	e9 c5 fe ff ff       	jmp    0xfffffffffffffed4
   f:	e8 98 03 09 00       	call   0x903ac
  14:	e9                   	.byte 0xe9
  15:	35                   	.byte 0x35
[ 1170.348874][    C1] RSP: 0018:ffffc900001e8df8 EFLAGS: 00010246
[ 1170.349049][    C1] RAX: 000000000000003e RBX: 0000000000000000 RCX: 1ffffffff75fb43c
[ 1170.349277][    C1] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001
[ 1170.349494][    C1] RBP: ffffea0000234534 R08: 0000000000000000 R09: fffffbfff75fb43c
[ 1170.349745][    C1] R10: 0000000000000003 R11: 205d314320202020 R12: ffffea0000234500
[ 1170.349944][    C1] R13: ffffc900001e8ec0 R14: 0000000000000000 R15: 0000000000000008
[ 1170.350164][    C1] FS:  00007fc03a56f740(0000) GS:ffff888036080000(0000) knlGS:0000000000000000
[ 1170.350460][    C1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1170.350630][    C1] CR2: 00007fc03a9c9270 CR3: 0000000012d32002 CR4: 0000000000772ef0
[ 1170.350830][    C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1170.351029][    C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1170.351250][    C1] PKRU: 55555554
[ 1170.351352][    C1] Call Trace:
[ 1170.351455][    C1]  <IRQ>
[ 1170.351538][ C1] ? die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434 arch/x86/kernel/dumpstack.c:447) 
[ 1170.351679][ C1] ? do_trap (arch/x86/kernel/traps.c:156 arch/x86/kernel/traps.c:197) 
[ 1170.351782][ C1] ? __free_pages (./include/linux/mm.h:1140 ./include/linux/mm.h:1138 mm/page_alloc.c:4819) 
[ 1170.351922][ C1] ? do_error_trap (./arch/x86/include/asm/traps.h:58 arch/x86/kernel/traps.c:218) 
[ 1170.352074][ C1] ? __free_pages (./include/linux/mm.h:1140 ./include/linux/mm.h:1138 mm/page_alloc.c:4819) 
[ 1170.352207][ C1] ? __free_pages (./include/linux/mm.h:1140 ./include/linux/mm.h:1138 mm/page_alloc.c:4819) 
[ 1170.352340][ C1] ? handle_invalid_op (arch/x86/kernel/traps.c:256) 
[ 1170.352472][ C1] ? __free_pages (./include/linux/mm.h:1140 ./include/linux/mm.h:1138 mm/page_alloc.c:4819) 
[ 1170.352606][ C1] ? exc_invalid_op (arch/x86/kernel/traps.c:315) 
[ 1170.352739][ C1] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621) 
[ 1170.352875][ C1] ? __free_pages (./include/linux/mm.h:1140 ./include/linux/mm.h:1138 mm/page_alloc.c:4819) 
[ 1170.353026][ C1] ? __free_pages (./include/linux/mm.h:1140 ./include/linux/mm.h:1138 mm/page_alloc.c:4819) 
[ 1170.353159][ C1] ? rcu_do_batch (kernel/rcu/tree.c:2567) 
[ 1170.353291][ C1] neigh_hash_free_rcu (net/core/neighbour.c:554) 
[ 1170.353441][ C1] rcu_do_batch (kernel/rcu/tree.c:2567) 
[ 1170.353578][ C1] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2491) 
[ 1170.353712][ C1] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4339 kernel/locking/lockdep.c:4406) 
[ 1170.353877][ C1] rcu_core (kernel/rcu/tree.c:2825) 
[ 1170.353978][ C1] handle_softirqs (kernel/softirq.c:554) 
[ 1170.354111][ C1] irq_exit_rcu (kernel/softirq.c:589 kernel/softirq.c:428 kernel/softirq.c:637 kernel/softirq.c:649) 
[ 1170.354216][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1037 arch/x86/kernel/apic/apic.c:1037) 
[ 1170.354348][    C1]  </IRQ>
[ 1170.354421][    C1]  <TASK>
[ 1170.354487][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 1170.354650][ C1] RIP: 0010:lock_is_held_type (kernel/locking/lockdep.c:122 kernel/locking/lockdep.c:5890) 
[ 1170.354787][ C1] Code: 69 d0 01 85 c9 0f 84 c0 00 00 00 65 8b 05 a3 c0 1b 46 85 c0 0f 85 b1 00 00 00 65 4c 8b 25 e3 fe 1c 46 41 8b 94 24 34 0a 00 00 <85> d2 0f 85 99 00 00 00 48 89 fd 41 89 f6 9c 8f 04 24 fa 65 ff 05
All code
========
   0:	69 d0 01 85 c9 0f    	imul   $0xfc98501,%eax,%edx
   6:	84 c0                	test   %al,%al
   8:	00 00                	add    %al,(%rax)
   a:	00 65 8b             	add    %ah,-0x75(%rbp)
   d:	05 a3 c0 1b 46       	add    $0x461bc0a3,%eax
  12:	85 c0                	test   %eax,%eax
  14:	0f 85 b1 00 00 00    	jne    0xcb
  1a:	65 4c 8b 25 e3 fe 1c 	mov    %gs:0x461cfee3(%rip),%r12        # 0x461cff05
  21:	46 
  22:	41 8b 94 24 34 0a 00 	mov    0xa34(%r12),%edx
  29:	00 
  2a:*	85 d2                	test   %edx,%edx		<-- trapping instruction
  2c:	0f 85 99 00 00 00    	jne    0xcb
  32:	48 89 fd             	mov    %rdi,%rbp
  35:	41 89 f6             	mov    %esi,%r14d
  38:	9c                   	pushf
  39:	8f 04 24             	pop    (%rsp)
  3c:	fa                   	cli
  3d:	65                   	gs
  3e:	ff                   	.byte 0xff
  3f:	05                   	.byte 0x5

Code starting with the faulting instruction
===========================================
   0:	85 d2                	test   %edx,%edx
   2:	0f 85 99 00 00 00    	jne    0xa1
   8:	48 89 fd             	mov    %rdi,%rbp
   b:	41 89 f6             	mov    %esi,%r14d
   e:	9c                   	pushf
   f:	8f 04 24             	pop    (%rsp)
  12:	fa                   	cli
  13:	65                   	gs
  14:	ff                   	.byte 0xff
  15:	05                   	.byte 0x5
[ 1170.355257][    C1] RSP: 0018:ffffc9000157fc60 EFLAGS: 00000246
[ 1170.355426][    C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
[ 1170.355625][    C1] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffffbb156ec0
[ 1170.355826][    C1] RBP: ffffffffba43a300 R08: 0000000000000000 R09: ffffed1000343558
[ 1170.356027][    C1] R10: ffff888001a1aac3 R11: 0000000000000000 R12: ffff888006728040
[ 1170.356233][    C1] R13: 00000000ffffffff R14: ffff888006c18680 R15: 0000000000000000
[ 1170.356435][ C1] __might_resched (kernel/sched/core.c:8600) 
[ 1170.356571][ C1] __might_fault (mm/memory.c:6699) 
[ 1170.356703][ C1] _copy_from_user (./arch/x86/include/asm/uaccess_64.h:98 ./include/linux/uaccess.h:162 lib/usercopy.c:18) 
[ 1170.356838][ C1] __sys_sendto (net/socket.c:252 net/socket.c:246 net/socket.c:2204) 
[ 1170.356976][ C1] ? __pfx___sys_sendto (net/socket.c:2184) 
[ 1170.357112][ C1] ? __might_fault (mm/memory.c:6700 mm/memory.c:6693) 
[ 1170.357249][ C1] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 1170.357382][ C1] ? lock_acquire (kernel/locking/lockdep.c:5798) 
[ 1170.357514][ C1] ? __might_fault (mm/memory.c:6700 mm/memory.c:6693) 
[ 1170.357645][ C1] ? trace_rseq_update (./include/trace/events/rseq.h:11 (discriminator 52)) 
[ 1170.357780][ C1] ? __pfx___rseq_handle_notify_resume (kernel/rseq.c:316) 
[ 1170.357946][ C1] ? __pfx_task_work_run (kernel/task_work.c:196) 
[ 1170.358080][ C1] __x64_sys_sendto (net/socket.c:2222) 
[ 1170.358241][ C1] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 1170.358409][ C1] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 1170.358568][ C1] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[ 1170.358737][    C1] RIP: 0033:0x7fc03a7c985a
[ 1170.358889][ C1] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89
All code
========
   0:	d8 64 89 02          	fsubs  0x2(%rcx,%rcx,4)
   4:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   b:	eb b8                	jmp    0xffffffffffffffc5
   d:	0f 1f 00             	nopl   (%rax)
  10:	f3 0f 1e fa          	endbr64
  14:	41 89 ca             	mov    %ecx,%r10d
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 15                	jne    0x38
  23:	b8 2c 00 00 00       	mov    $0x2c,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 7e                	ja     0xb0
  32:	c3                   	ret
  33:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  38:	41 54                	push   %r12
  3a:	48 83 ec 30          	sub    $0x30,%rsp
  3e:	44                   	rex.R
  3f:	89                   	.byte 0x89

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 7e                	ja     0x86
   8:	c3                   	ret
   9:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
   e:	41 54                	push   %r12
  10:	48 83 ec 30          	sub    $0x30,%rsp
  14:	44                   	rex.R
  15:	89                   	.byte 0x89
[ 1170.359423][    C1] RSP: 002b:00007ffca10e7e98 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[ 1170.359632][    C1] RAX: ffffffffffffffda RBX: 000000001fd1bec0 RCX: 00007fc03a7c985a
[ 1170.359854][    C1] RDX: 0000000000000070 RSI: 000000001fd1c160 RDI: 0000000000000005
[ 1170.360075][    C1] RBP: 000000001fd1bec0 R08: 00007ffca10e7ea0 R09: 000000000000001c
[ 1170.360310][    C1] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000070


Finger prints:
__free_pages:neigh_hash_free_rcu:rcu_do_batch:rcu_core:handle_softirqs