======================================
| [ 194.768410][ T789] #0: ffffffffa89e7a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink (net/core/rtnetlink.c:3512)
| [ 194.768676][ T789] #1: ffffffffa89d6630 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [  194.768982][  T789]
| [  194.768982][  T789] stack backtrace:
[  194.769381][  T789] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  194.769561][  T789] Call Trace:
[  194.769674][  T789]  <TASK>
[ 194.769750][ T789] dump_stack_lvl (lib/dump_stack.c:123)
[ 194.769902][ T789] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[ 194.770058][ T789] validate_chain (kernel/locking/lockdep.c:3894)
[ 194.770203][ T789] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 194.770351][ T789] ? 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)
[ 194.770496][ T789] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 194.770610][ T789] __lock_acquire (kernel/locking/lockdep.c:5226)
[ 194.770758][ T789] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 194.770905][ T789] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 194.771084][ T789] ? netconsole_process_cleanups_core (drivers/net/netconsole.c:242 (discriminator 11))
[ 194.771275][ T789] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 194.771430][ T789] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 194.771583][ T789] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 194.771729][ T789] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 194.771909][ T789] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[ 194.772019][ T789] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 194.772198][ T789] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[ 194.772349][ T789] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 194.772494][ T789] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[ 194.772638][ T789] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 194.772784][ T789] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 194.772931][ T789] __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))
[ 194.773077][ T789] ? __pfx___netdev_upper_dev_unlink (net/core/dev.c:8151)
[ 194.773261][ T789] ? __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)
[ 194.773407][ T789] ? __pfx___mutex_unlock_slowpath (kernel/locking/mutex.c:890)
[ 194.773589][ T789] ? rtnl_is_locked (net/core/rtnetlink.c:164)
[ 194.773741][ T789] netdev_upper_dev_unlink (net/core/dev.c:8190)
[ 194.773886][ T789] ? __pfx_netdev_upper_dev_unlink (net/core/dev.c:8190)
[ 194.774067][ T789] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[ 194.774213][ T789] ? 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)
[ 194.774363][ T789] ? rtnl_is_locked (net/core/rtnetlink.c:164)
[ 194.774509][ T789] ? netdev_master_upper_dev_get (net/core/dev.c:7230)
[ 194.774691][ T789] vrf_device_event (drivers/net/vrf.c:1110 drivers/net/vrf.c:1119 drivers/net/vrf.c:1804) vrf
[ 194.774840][ T789] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[ 194.774987][ T789] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[ 194.775133][ T789] unregister_netdevice_many_notify (net/core/dev.c:11571)
[ 194.775315][ T789] ? 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)
[ 194.775463][ T789] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 194.775573][ T789] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11512)
[ 194.775754][ T789] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[ 194.775939][ T789] ? kfree (mm/slub.c:4613 mm/slub.c:4761)
[ 194.776050][ T789] ? vlan_vid_del (net/8021q/vlan_core.c:368 net/8021q/vlan_core.c:387)
[ 194.776201][ T789] ? vlan_vid_del (net/8021q/vlan_core.c:368 net/8021q/vlan_core.c:387)
[ 194.776348][ T789] rtnl_dellink (net/core/rtnetlink.c:3478 net/core/rtnetlink.c:3518)
[ 194.776504][ T789] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3484)
[ 194.776666][ T789] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 194.776815][ T789] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 194.776963][ T789] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6900)
[ 194.777112][ T789] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 194.777257][ T789] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 194.777404][ T789] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6900)
[ 194.777557][ T789] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3484)
[ 194.777704][ T789] rtnetlink_rcv_msg (net/core/rtnetlink.c:6902)
[ 194.777850][ T789] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6805)
[ 194.777996][ T789] ? 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)
[ 194.778140][ T789] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 194.778253][ T789] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 194.778399][ T789] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[ 194.778547][ T789] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6805)
[ 194.778700][ T789] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[ 194.778852][ T789] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[ 194.779004][ T789] ? 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)
[ 194.779151][ T789] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[ 194.779296][ T789] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[ 194.779441][ T789] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 194.779587][ T789] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 194.779740][ T789] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[ 194.779888][ T789] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 194.780037][ T789] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[ 194.780181][ T789] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[ 194.780365][ T789] ___sys_sendmsg (net/socket.c:2650)
[ 194.780509][ T789] ? __pfx____sys_sendmsg (net/socket.c:2637)
[ 194.780658][ T789] ? kasan_save_stack (mm/kasan/common.c:49)
[ 194.780810][ T789] ? kasan_save_stack (mm/kasan/common.c:48)
[ 194.780954][ T789] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[ 194.781099][ T789] ? __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)
[ 194.781279][ T789] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[ 194.781433][ T789] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 194.781579][ T789] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 194.781765][ T789] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 194.781920][ T789] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 194.782068][ T789] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 194.782212][ T789] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[ 194.782361][ T789] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 194.782504][ T789] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 194.782650][ T789] __sys_sendmsg (net/socket.c:2680)
[ 194.782797][ T789] ? __pfx___sys_sendmsg (net/socket.c:2665)
[ 194.782950][ T789] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[ 194.783137][ T789] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 194.783282][ T789] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[  194.783461][  T789] RIP: 0033:0x7fc2861bf9a7
[ 194.783618][ T789] 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)
[  194.784146][  T789] RSP: 002b:00007ffda36075f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  194.784366][  T789] RAX: ffffffffffffffda RBX: 00007ffda3607d20 RCX: 00007fc2861bf9a7
[  194.784585][  T789] RDX: 0000000000000000 RSI: 00007ffda3607660 RDI: 0000000000000005
[  194.784802][  T789] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078
[  194.785026][  T789] R10: 00007fc28607def8 R11: 0000000000000246 R12: 0000000000000002


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