======================================
| [  786.816900][T12621] 1 lock held by arping/12621:
| [  786.817069][T12621]  #0: ffffffff8c791e60 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit (./include/linux/bottom_half.h:20 (discriminator 2) ./include/linux/rcupdate.h:893 (discriminator 2) net/core/dev.c:4796 (discriminator 2))
| [  786.817328][T12621]
| [  786.817328][T12621] stack backtrace:
[  786.817529][T12621] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  786.817531][T12621] Call Trace:
[  786.817533][T12621]  <TASK>
[  786.817535][T12621]  dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)
[  786.817542][T12621]  lockdep_rcu_suspicious.cold (kernel/locking/lockdep.c:6876)
[  786.817548][T12621] arp_reduce.isra.0 (drivers/net/vxlan/vxlan_core.c:1872 (discriminator 11)) vxlan
[  786.817556][T12621]  ? mark_usage (kernel/locking/lockdep.c:4674)
[  786.817560][T12621]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[  786.817564][T12621]  ? vxlan_nl2conf (drivers/net/vxlan/vxlan_core.c:4326 (discriminator 2)) vxlan
[  786.817569][T12621]  ? lock_acquire.part.0 (kernel/locking/lockdep.c:5868 (discriminator 1))
[  786.817571][T12621]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[  786.817574][T12621]  ? __lock_release.isra.0 (kernel/locking/lockdep.c:5535)
[  786.817578][T12621]  ? vxlan_xmit (drivers/net/vxlan/vxlan_core.c:2801) vxlan
[  786.817582][T12621] vxlan_xmit (drivers/net/vxlan/vxlan_core.c:2801) vxlan
[  786.817587][T12621]  ? rcu_lockdep_current_cpu_online (kernel/rcu/tree.c:4069 (discriminator 3) kernel/rcu/tree.c:4061 (discriminator 3))
[  786.817592][T12621]  dev_hard_start_xmit (./include/linux/netdevice.h:5403 ./include/linux/netdevice.h:5412 net/core/dev.c:3892 net/core/dev.c:3908)
[  786.817595][T12621]  ? validate_xmit_skb (net/core/dev.c:4032)
[  786.817598][T12621]  __dev_queue_xmit (net/core/dev.c:4875)
[  786.817600][T12621]  ? _copy_from_iter (./include/linux/instrumented.h:146 lib/iov_iter.c:66 ./include/linux/iov_iter.h:30 ./include/linux/iov_iter.h:302 ./include/linux/iov_iter.h:330 lib/iov_iter.c:261 lib/iov_iter.c:272)
[  786.817604][T12621]  ? __alloc_skb (./include/linux/instrumented.h:97 ./include/linux/atomic/atomic-instrumented.h:67 net/core/skbuff.c:410 net/core/skbuff.c:722)
[  786.817608][T12621]  ? _copy_from_iter_flushcache (./include/linux/iov_iter.h:112)
[  786.817610][T12621]  ? ref_tracker_alloc (./include/linux/instrumented.h:112 ./include/linux/atomic/atomic-instrumented.h:252 ./include/linux/refcount.h:283 ./include/linux/refcount.h:366 ./include/linux/refcount.h:383 lib/ref_tracker.c:265)
[  786.817613][T12621]  ? netdev_core_pick_tx (net/core/dev.c:4736)
[  786.817617][T12621]  ? packet_parse_headers (./include/linux/skbuff.h:1625 ./include/linux/skbuff.h:3196 net/packet/af_packet.c:1939)
[  786.817620][T12621]  ? __asan_memset (mm/kasan/shadow.c:84 (discriminator 1))
[  786.817623][T12621]  ? packet_parse_headers (./include/linux/skbuff.h:1625 ./include/linux/skbuff.h:3196 net/packet/af_packet.c:1939)
[  786.817626][T12621]  ? skb_copy_datagram_from_iter (./include/linux/uio.h:228 net/core/datagram.c:561)
[  786.817628][T12621]  ? packet_release (net/packet/af_packet.c:3171)
[  786.817632][T12621]  packet_snd (net/packet/af_packet.c:3082)
[  786.817638][T12621]  ? tpacket_snd (net/packet/af_packet.c:2685)
[  786.817639][T12621]  ? __might_fault (mm/memory.c:7292 (discriminator 5))
[  786.817645][T12621]  ? __might_fault (mm/memory.c:7292 (discriminator 5))
[  786.817647][T12621]  ? __might_fault (mm/memory.c:7292 (discriminator 5))
[  786.817651][T12621]  __sys_sendto (net/socket.c:775 (discriminator 4) net/socket.c:790 (discriminator 4) net/socket.c:2252 (discriminator 4))
[  786.817654][T12621]  ? __ia32_sys_getpeername (net/socket.c:2206)
[  786.817662][T12621]  ? do_user_addr_fault (./include/linux/mmap_lock.h:619 arch/x86/mm/fault.c:1422)
[  786.817668][T12621]  __x64_sys_sendto (net/socket.c:2259 net/socket.c:2255 net/socket.c:2255)
[  786.817669][T12621]  ? trace_irq_enable.constprop.0 (./include/trace/events/preemptirq.h:40 (discriminator 22))
[  786.817673][T12621]  ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4472)
[  786.817676][T12621]  ? do_syscall_64 (./include/linux/entry-common.h:177 arch/x86/entry/syscall_64.c:89)
[  786.817678][T12621]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[  786.817680][T12621]  ? trace_hardirqs_off (kernel/trace/trace_preemptirq.c:104 (discriminator 1))
[  786.817682][T12621]  ? exc_page_fault (arch/x86/mm/fault.c:1489 (discriminator 3) arch/x86/mm/fault.c:1536 (discriminator 3))
[  786.817685][T12621]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
[  786.817687][T12621] RIP: 0033:0x7f847ed9254e
[  786.817690][T12621] Code: 4d 89 d8 e8 b4 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 b4 bd 00 00       	call   0xbdbc
   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
[  786.817692][T12621] RSP: 002b:00007ffccb1d6050 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
[  786.817695][T12621] RAX: ffffffffffffffda RBX: 000000000000001c RCX: 00007f847ed9254e
[  786.817697][T12621] RDX: 000000000000001c RSI: 00007ffccb1d60d0 RDI: 0000000000000005
[  786.817698][T12621] RBP: 00007ffccb1d6060 R08: 00007ffccb1d6550 R09: 0000000000000014
[  786.817698][T12621] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000


Finger prints:
vxlan_xmit:dev_hard_start_xmit:__dev_queue_xmit:packet_snd:__sys_sendto