======================================
| [ 142.037506][ T3419] #0: ffffffffb9c07e88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink (net/core/rtnetlink.c:3521)
| [ 142.037772][ T3419] #1: ffffffffb9bf6a70 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [  142.038061][ T3419]
| [  142.038061][ T3419] stack backtrace:
[  142.038457][ T3419] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  142.038639][ T3419] Call Trace:
[  142.038750][ T3419]  <TASK>
[ 142.038827][ T3419] dump_stack_lvl (lib/dump_stack.c:123)
[ 142.038976][ T3419] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[ 142.039124][ T3419] validate_chain (kernel/locking/lockdep.c:3894)
[ 142.039270][ T3419] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 142.039417][ T3419] ? 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)
[ 142.039564][ T3419] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 142.039676][ T3419] __lock_acquire (kernel/locking/lockdep.c:5226)
[ 142.039825][ T3419] ? arch_stack_walk (arch/x86/kernel/stacktrace.c:17)
[ 142.039974][ T3419] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 142.040119][ T3419] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 142.040298][ T3419] ? find_stack (lib/stackdepot.c:552 (discriminator 1))
[ 142.040444][ T3419] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 142.040590][ T3419] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 142.040736][ T3419] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 142.040884][ T3419] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 142.041065][ T3419] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[ 142.041178][ T3419] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 142.041358][ T3419] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[ 142.041502][ T3419] ? netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 142.041648][ T3419] ? ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 142.041794][ T3419] ? ___sys_sendmsg (net/socket.c:2650)
[ 142.041940][ T3419] ? __sys_sendmsg (net/socket.c:2680)
[ 142.042086][ T3419] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 142.042232][ T3419] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 142.042415][ T3419] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 142.042560][ T3419] __netdev_upper_dev_unlink (net/core/dev.c:8000 (discriminator 11) net/core/dev.c:8017 (discriminator 11) net/core/dev.c:8167 (discriminator 11))
[ 142.042705][ T3419] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 142.042850][ T3419] ? __pfx___netdev_upper_dev_unlink (net/core/dev.c:8151)
[ 142.043051][ T3419] ? 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)
[ 142.043198][ T3419] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 142.043306][ T3419] ? 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)
[ 142.043451][ T3419] netdev_upper_dev_unlink (net/core/dev.c:8190)
[ 142.043597][ T3419] ? __pfx_netdev_upper_dev_unlink (net/core/dev.c:8190)
[ 142.043776][ T3419] unregister_vlan_dev (net/8021q/vlan.c:118)
[ 142.043925][ T3419] vlan_device_event (net/8021q/vlan.c:489)
[ 142.044072][ T3419] ? __pfx_vlan_device_event (net/8021q/vlan.c:362)
[ 142.044222][ T3419] ? __pfx_br_device_event (net/bridge/br.c:29)
[ 142.044368][ T3419] ? packet_notifier (net/packet/af_packet.c:4282)
[ 142.044515][ T3419] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[ 142.044662][ T3419] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[ 142.044809][ T3419] unregister_netdevice_many_notify (net/core/dev.c:11575)
[ 142.044993][ T3419] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11516)
[ 142.045176][ T3419] ? vxlan_dellink (drivers/net/vxlan/vxlan_core.c:4494) vxlan
[ 142.045336][ T3419] ? __nla_validate_parse (./include/net/netlink.h:1270 (discriminator 1) lib/nlattr.c:622 (discriminator 1))
[ 142.045482][ T3419] rtnl_dellink (net/core/rtnetlink.c:3487 net/core/rtnetlink.c:3527)
[ 142.045627][ T3419] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3493)
[ 142.045784][ T3419] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 142.045934][ T3419] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 142.046077][ T3419] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[ 142.046223][ T3419] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 142.046366][ T3419] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 142.046513][ T3419] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[ 142.046658][ T3419] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3493)
[ 142.046802][ T3419] rtnetlink_rcv_msg (net/core/rtnetlink.c:6911)
[ 142.046948][ T3419] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 142.047094][ T3419] ? 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)
[ 142.047239][ T3419] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 142.047350][ T3419] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 142.047494][ T3419] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[ 142.047638][ T3419] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 142.047783][ T3419] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[ 142.047931][ T3419] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[ 142.048076][ T3419] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/net/netns/generic.h:48 net/netlink/af_netlink.c:333)
[ 142.048226][ T3419] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[ 142.048371][ T3419] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[ 142.048515][ T3419] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 142.048660][ T3419] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 142.048807][ T3419] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[ 142.048956][ T3419] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 142.049100][ T3419] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[ 142.049244][ T3419] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[ 142.049429][ T3419] ___sys_sendmsg (net/socket.c:2650)
[ 142.049576][ T3419] ? __pfx____sys_sendmsg (net/socket.c:2637)
[ 142.049721][ T3419] ? kasan_save_stack (mm/kasan/common.c:49)
[ 142.049866][ T3419] ? kasan_save_stack (mm/kasan/common.c:48)
[ 142.050011][ T3419] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[ 142.050161][ T3419] ? __call_rcu_common.constprop.0 (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:87 ./arch/x86/include/asm/irqflags.h:123 kernel/rcu/tree.c:3087)
[ 142.050342][ T3419] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[ 142.050491][ T3419] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 142.050636][ T3419] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 142.050814][ T3419] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 142.050962][ T3419] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 142.051107][ T3419] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 142.051251][ T3419] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[ 142.051398][ T3419] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 142.051545][ T3419] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 142.051692][ T3419] __sys_sendmsg (net/socket.c:2680)
[ 142.051838][ T3419] ? __pfx___sys_sendmsg (net/socket.c:2665)
[ 142.051983][ T3419] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[ 142.052168][ T3419] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 142.052312][ T3419] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[  142.052490][ T3419] RIP: 0033:0x7fe0caf579a7
[ 142.052643][ T3419] Code: 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
All code
========
   0:	0a 00                	or     (%rax),%al
   2:	f7 d8                	neg    %eax
   4:	64 89 02             	mov    %eax,%fs:(%rdx)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b9                	jmp    0xffffffffffffffc9
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 2e 00 00 00       	mov    $0x2e,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  3b:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  11:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)
[  142.053190][ T3419] RSP: 002b:00007ffd684eaab8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  142.053410][ T3419] RAX: ffffffffffffffda RBX: 00007ffd684eb1f0 RCX: 00007fe0caf579a7
[  142.053630][ T3419] RDX: 0000000000000000 RSI: 00007ffd684eab20 RDI: 0000000000000005
[  142.053846][ T3419] RBP: 0000000000000001 R08: 0000000000000003 R09: 0000000000000078
[  142.054063][ T3419] R10: 00007fe0cae154a8 R11: 0000000000000246 R12: 0000000000000001


Finger prints:
print_deadlock_bug:validate_chain:__lock_acquire:down_read:blocking_notifier_call_chain