======================================
| [701.372307][T11619] #0: ffffffff98be7a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink (net/core/rtnetlink.c:3512)
| [701.372585][T11619] #1: ffffffff98bd6630 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [  701.372884][T11619]
| [  701.372884][T11619] stack backtrace:
[  701.373287][T11619] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  701.373479][T11619] Call Trace:
[  701.373593][T11619]  <TASK>
[701.373672][T11619] dump_stack_lvl (lib/dump_stack.c:123)
[701.373831][T11619] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[701.373981][T11619] validate_chain (kernel/locking/lockdep.c:3894)
[701.374132][T11619] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[701.374283][T11619] ? 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)
[701.374430][T11619] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[701.374550][T11619] __lock_acquire (kernel/locking/lockdep.c:5226)
[701.374698][T11619] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[701.374846][T11619] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[701.375031][T11619] ? netconsole_process_cleanups_core (drivers/net/netconsole.c:242 (discriminator 11))
[701.375217][T11619] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[701.375389][T11619] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[701.375541][T11619] ? lock_acquire (kernel/locking/lockdep.c:5822)
[701.375697][T11619] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[701.375879][T11619] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[701.375993][T11619] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[701.376194][T11619] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[701.376343][T11619] ? __lock_release (kernel/locking/lockdep.c:5525)
[701.376490][T11619] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[701.376638][T11619] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[701.376795][T11619] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[701.376942][T11619] __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))
[701.377092][T11619] ? __pfx___netdev_upper_dev_unlink (net/core/dev.c:8151)
[701.377276][T11619] ? __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)
[701.377426][T11619] ? __pfx___mutex_unlock_slowpath (kernel/locking/mutex.c:890)
[701.377608][T11619] ? rtnl_is_locked (net/core/rtnetlink.c:164)
[701.377761][T11619] netdev_upper_dev_unlink (net/core/dev.c:8190)
[701.377915][T11619] ? __pfx_netdev_upper_dev_unlink (net/core/dev.c:8190)
[701.378099][T11619] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[701.378246][T11619] ? 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)
[701.378394][T11619] ? rtnl_is_locked (net/core/rtnetlink.c:164)
[701.378542][T11619] ? netdev_master_upper_dev_get (net/core/dev.c:7230)
[701.378732][T11619] vrf_device_event (drivers/net/vrf.c:1110 drivers/net/vrf.c:1119 drivers/net/vrf.c:1804) vrf
[701.378893][T11619] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[701.379044][T11619] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[701.379193][T11619] unregister_netdevice_many_notify (net/core/dev.c:11571)
[701.379379][T11619] ? 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)
[701.379526][T11619] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[701.379639][T11619] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11512)
[701.379823][T11619] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[701.380013][T11619] ? kfree (mm/slub.c:4613 mm/slub.c:4761)
[701.380127][T11619] ? vlan_vid_del (net/8021q/vlan_core.c:368 net/8021q/vlan_core.c:387)
[701.380282][T11619] ? vlan_vid_del (net/8021q/vlan_core.c:368 net/8021q/vlan_core.c:387)
[701.380436][T11619] rtnl_dellink (net/core/rtnetlink.c:3478 net/core/rtnetlink.c:3518)
[701.380595][T11619] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3484)
[701.380758][T11619] ? find_held_lock (kernel/locking/lockdep.c:5339)
[701.380908][T11619] ? __lock_release (kernel/locking/lockdep.c:5525)
[701.381056][T11619] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6900)
[701.381213][T11619] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[701.381360][T11619] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[701.381510][T11619] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6900)
[701.381658][T11619] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3484)
[701.381809][T11619] rtnetlink_rcv_msg (net/core/rtnetlink.c:6902)
[701.381959][T11619] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6805)
[701.382108][T11619] ? 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)
[701.382264][T11619] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[701.382378][T11619] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[701.382528][T11619] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[701.382680][T11619] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6805)
[701.382828][T11619] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[701.382978][T11619] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[701.383126][T11619] ? 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)
[701.383283][T11619] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[701.383431][T11619] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[701.383577][T11619] ? find_held_lock (kernel/locking/lockdep.c:5339)
[701.383727][T11619] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[701.383878][T11619] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[701.384030][T11619] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[701.384179][T11619] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[701.384333][T11619] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[701.384522][T11619] ___sys_sendmsg (net/socket.c:2650)
[701.384670][T11619] ? __pfx____sys_sendmsg (net/socket.c:2637)
[701.384817][T11619] ? kasan_save_stack (mm/kasan/common.c:49)
[701.384964][T11619] ? kasan_save_stack (mm/kasan/common.c:48)
[701.385111][T11619] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[701.385263][T11619] ? __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)
[701.385453][T11619] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[701.385602][T11619] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[701.385755][T11619] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[701.385940][T11619] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[701.386090][T11619] ? find_held_lock (kernel/locking/lockdep.c:5339)
[701.386252][T11619] ? __lock_release (kernel/locking/lockdep.c:5525)
[701.386400][T11619] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[701.386551][T11619] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[701.386704][T11619] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[701.386855][T11619] __sys_sendmsg (net/socket.c:2680)
[701.387003][T11619] ? __pfx___sys_sendmsg (net/socket.c:2665)
[701.387150][T11619] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[701.387338][T11619] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[701.387487][T11619] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[  701.387670][T11619] RIP: 0033:0x7fc163aa49a7
[ 701.387837][T11619] 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)
[  701.388356][T11619] RSP: 002b:00007fff63dd35a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  701.388580][T11619] RAX: ffffffffffffffda RBX: 00007fff63dd3cd0 RCX: 00007fc163aa49a7
[  701.388811][T11619] RDX: 0000000000000000 RSI: 00007fff63dd3610 RDI: 0000000000000005
[  701.389033][T11619] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078
[  701.389255][T11619] R10: 00007fc163962ef8 R11: 0000000000000246 R12: 0000000000000002


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