======================================
| [771.141653][T11104] #0: ffffffff967e7a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink (net/core/rtnetlink.c:3512)
| [771.141960][T11104] #1: ffffffff967d6630 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [  771.142291][T11104]
| [  771.142291][T11104] stack backtrace:
[  771.142741][T11104] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  771.142947][T11104] Call Trace:
[  771.143075][T11104]  <TASK>
[771.143162][T11104] dump_stack_lvl (lib/dump_stack.c:123)
[771.143332][T11104] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[771.143499][T11104] validate_chain (kernel/locking/lockdep.c:3894)
[771.143666][T11104] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[771.143832][T11104] ? 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)
[771.143990][T11104] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[771.144118][T11104] __lock_acquire (kernel/locking/lockdep.c:5226)
[771.144281][T11104] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[771.144443][T11104] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[771.144641][T11104] ? netconsole_process_cleanups_core (drivers/net/netconsole.c:242 (discriminator 11))
[771.144846][T11104] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[771.145008][T11104] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[771.145171][T11104] ? lock_acquire (kernel/locking/lockdep.c:5822)
[771.145337][T11104] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[771.145539][T11104] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[771.145668][T11104] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[771.145869][T11104] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[771.146032][T11104] ? __lock_release (kernel/locking/lockdep.c:5525)
[771.146194][T11104] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[771.146361][T11104] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[771.146524][T11104] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[771.146697][T11104] __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))
[771.146861][T11104] ? __pfx___netdev_upper_dev_unlink (net/core/dev.c:8151)
[771.147062][T11104] ? __mutex_unlock_slowpath (./arch/x86/include/asm/atomic64_64.h:101 ./include/linux/atomic/atomic-arch-fallback.h:4329 ./include/linux/atomic/atomic-long.h:1506 ./include/linux/atomic/atomic-instrumented.h:4481 kernel/locking/mutex.c:913)
[771.147228][T11104] ? __pfx___mutex_unlock_slowpath (kernel/locking/mutex.c:890)
[771.147431][T11104] ? rtnl_is_locked (net/core/rtnetlink.c:164)
[771.147596][T11104] netdev_upper_dev_unlink (net/core/dev.c:8190)
[771.147765][T11104] ? __pfx_netdev_upper_dev_unlink (net/core/dev.c:8190)
[771.147964][T11104] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[771.148126][T11104] ? mutex_is_locked (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-long.h:38 ./include/linux/atomic/atomic-instrumented.h:3189 kernel/locking/mutex.h:47 kernel/locking/mutex.c:66)
[771.148286][T11104] ? rtnl_is_locked (net/core/rtnetlink.c:164)
[771.148445][T11104] ? netdev_master_upper_dev_get (net/core/dev.c:7230)
[771.148644][T11104] vrf_device_event (drivers/net/vrf.c:1110 drivers/net/vrf.c:1119 drivers/net/vrf.c:1804) vrf
[771.148808][T11104] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[771.148975][T11104] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[771.149139][T11104] unregister_netdevice_many_notify (net/core/dev.c:11571)
[771.149338][T11104] ? 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)
[771.149497][T11104] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[771.149623][T11104] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11512)
[771.149820][T11104] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[771.150023][T11104] ? kfree (mm/slub.c:4613 mm/slub.c:4761)
[771.150150][T11104] ? vlan_vid_del (net/8021q/vlan_core.c:368 net/8021q/vlan_core.c:387)
[771.150312][T11104] ? vlan_vid_del (net/8021q/vlan_core.c:368 net/8021q/vlan_core.c:387)
[771.150474][T11104] rtnl_dellink (net/core/rtnetlink.c:3478 net/core/rtnetlink.c:3518)
[771.150635][T11104] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3484)
[771.150809][T11104] ? find_held_lock (kernel/locking/lockdep.c:5339)
[771.150971][T11104] ? __lock_release (kernel/locking/lockdep.c:5525)
[771.151130][T11104] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6900)
[771.151288][T11104] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[771.151454][T11104] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[771.151616][T11104] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6900)
[771.151777][T11104] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3484)
[771.151940][T11104] rtnetlink_rcv_msg (net/core/rtnetlink.c:6902)
[771.152101][T11104] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6805)
[771.152272][T11104] ? 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)
[771.152431][T11104] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[771.152558][T11104] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[771.152719][T11104] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[771.152881][T11104] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6805)
[771.153040][T11104] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[771.153204][T11104] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[771.153366][T11104] ? 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)
[771.153527][T11104] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[771.153691][T11104] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[771.153851][T11104] ? find_held_lock (kernel/locking/lockdep.c:5339)
[771.154013][T11104] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[771.154172][T11104] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[771.154337][T11104] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[771.154498][T11104] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[771.154658][T11104] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[771.154872][T11104] ___sys_sendmsg (net/socket.c:2650)
[771.155029][T11104] ? __pfx____sys_sendmsg (net/socket.c:2637)
[771.155188][T11104] ? kasan_save_stack (mm/kasan/common.c:49)
[771.155348][T11104] ? kasan_save_stack (mm/kasan/common.c:48)
[771.155506][T11104] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[771.155664][T11104] ? __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)
[771.155865][T11104] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[771.156030][T11104] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[771.156190][T11104] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[771.156390][T11104] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[771.156553][T11104] ? find_held_lock (kernel/locking/lockdep.c:5339)
[771.156714][T11104] ? __lock_release (kernel/locking/lockdep.c:5525)
[771.156872][T11104] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[771.157035][T11104] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[771.157197][T11104] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[771.157364][T11104] __sys_sendmsg (net/socket.c:2680)
[771.157525][T11104] ? __pfx___sys_sendmsg (net/socket.c:2665)
[771.157687][T11104] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[771.157890][T11104] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[771.158050][T11104] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[  771.158245][T11104] RIP: 0033:0x7f32570159a7
[ 771.158412][T11104] 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)
[  771.158984][T11104] RSP: 002b:00007ffc540b3d78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  771.159224][T11104] RAX: ffffffffffffffda RBX: 00007ffc540b44a0 RCX: 00007f32570159a7
[  771.159471][T11104] RDX: 0000000000000000 RSI: 00007ffc540b3de0 RDI: 0000000000000005
[  771.159708][T11104] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078
[  771.159948][T11104] R10: 00007f3256ed3ef8 R11: 0000000000000246 R12: 0000000000000002


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