======================================
| [ 148.006443][ T3418] #0: ffffffffa2207e88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink (net/core/rtnetlink.c:3521)
| [ 148.006709][ T3418] #1: ffffffffa21f6a70 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [  148.006998][ T3418]
| [  148.006998][ T3418] stack backtrace:
[  148.007394][ T3418] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  148.007573][ T3418] Call Trace:
[  148.007684][ T3418]  <TASK>
[ 148.007760][ T3418] dump_stack_lvl (lib/dump_stack.c:123)
[ 148.007910][ T3418] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[ 148.008057][ T3418] validate_chain (kernel/locking/lockdep.c:3894)
[ 148.008202][ T3418] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 148.008353][ T3418] ? 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)
[ 148.008498][ T3418] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 148.008610][ T3418] __lock_acquire (kernel/locking/lockdep.c:5226)
[ 148.008755][ T3418] ? arch_stack_walk (arch/x86/kernel/stacktrace.c:17)
[ 148.008902][ T3418] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 148.009048][ T3418] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 148.009228][ T3418] ? find_stack (lib/stackdepot.c:552 (discriminator 1))
[ 148.009379][ T3418] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 148.009523][ T3418] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 148.009670][ T3418] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 148.009814][ T3418] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 148.009993][ T3418] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[ 148.010105][ T3418] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 148.010284][ T3418] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[ 148.010432][ T3418] ? netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 148.010580][ T3418] ? ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 148.010726][ T3418] ? ___sys_sendmsg (net/socket.c:2650)
[ 148.010872][ T3418] ? __sys_sendmsg (net/socket.c:2680)
[ 148.011015][ T3418] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 148.011161][ T3418] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 148.011344][ T3418] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 148.011490][ T3418] __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))
[ 148.011638][ T3418] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 148.011783][ T3418] ? __pfx___netdev_upper_dev_unlink (net/core/dev.c:8151)
[ 148.011976][ T3418] ? 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)
[ 148.012119][ T3418] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 148.012229][ T3418] ? 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)
[ 148.012375][ T3418] netdev_upper_dev_unlink (net/core/dev.c:8190)
[ 148.012520][ T3418] ? __pfx_netdev_upper_dev_unlink (net/core/dev.c:8190)
[ 148.012704][ T3418] unregister_vlan_dev (net/8021q/vlan.c:118)
[ 148.012851][ T3418] vlan_device_event (net/8021q/vlan.c:489)
[ 148.012998][ T3418] ? __pfx_vlan_device_event (net/8021q/vlan.c:362)
[ 148.013144][ T3418] ? __pfx_br_device_event (net/bridge/br.c:29)
[ 148.013292][ T3418] ? packet_notifier (net/packet/af_packet.c:4282)
[ 148.013441][ T3418] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[ 148.013587][ T3418] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[ 148.013738][ T3418] unregister_netdevice_many_notify (net/core/dev.c:11575)
[ 148.013919][ T3418] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11516)
[ 148.014098][ T3418] ? vxlan_dellink (drivers/net/vxlan/vxlan_core.c:4494) vxlan
[ 148.014259][ T3418] ? __nla_validate_parse (./include/net/netlink.h:1270 (discriminator 1) lib/nlattr.c:622 (discriminator 1))
[ 148.014405][ T3418] rtnl_dellink (net/core/rtnetlink.c:3487 net/core/rtnetlink.c:3527)
[ 148.014551][ T3418] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3493)
[ 148.014715][ T3418] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 148.014859][ T3418] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 148.015002][ T3418] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[ 148.015145][ T3418] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 148.015288][ T3418] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 148.015437][ T3418] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[ 148.015581][ T3418] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3493)
[ 148.015728][ T3418] rtnetlink_rcv_msg (net/core/rtnetlink.c:6911)
[ 148.015871][ T3418] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 148.016016][ T3418] ? 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)
[ 148.016158][ T3418] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 148.016269][ T3418] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 148.016414][ T3418] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[ 148.016558][ T3418] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 148.016703][ T3418] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[ 148.016855][ T3418] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[ 148.017000][ T3418] ? 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)
[ 148.017146][ T3418] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[ 148.017293][ T3418] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[ 148.017438][ T3418] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 148.017582][ T3418] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 148.017728][ T3418] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[ 148.017879][ T3418] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 148.018025][ T3418] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[ 148.018168][ T3418] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[ 148.018353][ T3418] ___sys_sendmsg (net/socket.c:2650)
[ 148.018499][ T3418] ? __pfx____sys_sendmsg (net/socket.c:2637)
[ 148.018645][ T3418] ? kasan_save_stack (mm/kasan/common.c:49)
[ 148.018790][ T3418] ? kasan_save_stack (mm/kasan/common.c:48)
[ 148.018938][ T3418] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[ 148.019083][ T3418] ? __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)
[ 148.019266][ T3418] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[ 148.019414][ T3418] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 148.019559][ T3418] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 148.019736][ T3418] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 148.019881][ T3418] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 148.020028][ T3418] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 148.020173][ T3418] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[ 148.020320][ T3418] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 148.020464][ T3418] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 148.020608][ T3418] __sys_sendmsg (net/socket.c:2680)
[ 148.020754][ T3418] ? __pfx___sys_sendmsg (net/socket.c:2665)
[ 148.020898][ T3418] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[ 148.021089][ T3418] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 148.021233][ T3418] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[  148.021410][ T3418] RIP: 0033:0x7f616fc059a7
[ 148.021562][ T3418] 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)
[  148.022081][ T3418] RSP: 002b:00007ffd363af4d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  148.022299][ T3418] RAX: ffffffffffffffda RBX: 00007ffd363afc10 RCX: 00007f616fc059a7
[  148.022517][ T3418] RDX: 0000000000000000 RSI: 00007ffd363af540 RDI: 0000000000000005
[  148.022732][ T3418] RBP: 0000000000000001 R08: 0000000000000003 R09: 0000000000000078
[  148.022950][ T3418] R10: 00007f616fac34a8 R11: 0000000000000246 R12: 0000000000000001


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