======================================
| [1138.900700][T17310] #0: ffffffff9afe7a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink (net/core/rtnetlink.c:3521)
| [1138.901026][T17310] #1: ffffffff9afd6630 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [ 1138.901393][T17310]
| [ 1138.901393][T17310] stack backtrace:
[ 1138.901889][T17310] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 1138.902122][T17310] Call Trace:
[ 1138.902271][T17310]  <TASK>
[1138.902383][T17310] dump_stack_lvl (lib/dump_stack.c:123)
[1138.902571][T17310] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[1138.902754][T17310] validate_chain (kernel/locking/lockdep.c:3894)
[1138.902938][T17310] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[1138.903122][T17310] ? 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)
[1138.903304][T17310] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[1138.903443][T17310] __lock_acquire (kernel/locking/lockdep.c:5226)
[1138.903631][T17310] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[1138.903818][T17310] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[1138.904038][T17310] ? netconsole_process_cleanups_core (drivers/net/netconsole.c:242 (discriminator 11))
[1138.904259][T17310] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[1138.904435][T17310] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[1138.904613][T17310] ? lock_acquire (kernel/locking/lockdep.c:5822)
[1138.904790][T17310] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[1138.905014][T17310] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[1138.905148][T17310] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[1138.905368][T17310] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[1138.905547][T17310] ? __lock_release (kernel/locking/lockdep.c:5525)
[1138.905724][T17310] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[1138.905901][T17310] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[1138.906078][T17310] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[1138.906260][T17310] __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))
[1138.906455][T17310] ? __pfx___netdev_upper_dev_unlink (net/core/dev.c:8151)
[1138.906680][T17310] ? __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)
[1138.906861][T17310] ? __pfx___mutex_unlock_slowpath (kernel/locking/mutex.c:890)
[1138.907089][T17310] ? rtnl_is_locked (net/core/rtnetlink.c:163)
[1138.907280][T17310] netdev_upper_dev_unlink (net/core/dev.c:8190)
[1138.907465][T17310] ? __pfx_netdev_upper_dev_unlink (net/core/dev.c:8190)
[1138.907690][T17310] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[1138.907880][T17310] ? 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)
[1138.908061][T17310] ? rtnl_is_locked (net/core/rtnetlink.c:163)
[1138.908239][T17310] ? netdev_master_upper_dev_get (net/core/dev.c:7230)
[1138.908472][T17310] vrf_device_event (drivers/net/vrf.c:1110 drivers/net/vrf.c:1119 drivers/net/vrf.c:1804) vrf
[1138.908652][T17310] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[1138.908835][T17310] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[1138.909011][T17310] unregister_netdevice_many_notify (net/core/dev.c:11575)
[1138.909230][T17310] ? 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)
[1138.909404][T17310] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[1138.909542][T17310] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11516)
[1138.909760][T17310] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406)
[1138.909982][T17310] ? kfree (mm/slub.c:4613 mm/slub.c:4761)
[1138.910161][T17310] ? vlan_vid_del (net/8021q/vlan_core.c:368 net/8021q/vlan_core.c:387)
[1138.910349][T17310] ? vlan_vid_del (net/8021q/vlan_core.c:368 net/8021q/vlan_core.c:387)
[1138.910533][T17310] rtnl_dellink (net/core/rtnetlink.c:3487 net/core/rtnetlink.c:3527)
[1138.910718][T17310] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3493)
[1138.910913][T17310] ? find_held_lock (kernel/locking/lockdep.c:5339)
[1138.911096][T17310] ? __lock_release (kernel/locking/lockdep.c:5525)
[1138.911277][T17310] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[1138.911457][T17310] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[1138.911641][T17310] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[1138.911840][T17310] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[1138.912016][T17310] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3493)
[1138.912193][T17310] rtnetlink_rcv_msg (net/core/rtnetlink.c:6911)
[1138.912371][T17310] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[1138.912545][T17310] ? 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)
[1138.912721][T17310] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[1138.912860][T17310] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[1138.913035][T17310] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[1138.913229][T17310] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[1138.913409][T17310] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[1138.913596][T17310] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[1138.913778][T17310] ? 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)
[1138.913959][T17310] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[1138.914143][T17310] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[1138.914325][T17310] ? find_held_lock (kernel/locking/lockdep.c:5339)
[1138.914506][T17310] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[1138.914688][T17310] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[1138.914877][T17310] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[1138.915060][T17310] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[1138.915239][T17310] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[1138.915471][T17310] ___sys_sendmsg (net/socket.c:2650)
[1138.915659][T17310] ? __pfx____sys_sendmsg (net/socket.c:2637)
[1138.915836][T17310] ? kasan_save_stack (mm/kasan/common.c:49)
[1138.916011][T17310] ? kasan_save_stack (mm/kasan/common.c:48)
[1138.916185][T17310] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[1138.916361][T17310] ? __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)
[1138.916582][T17310] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[1138.916765][T17310] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[1138.916965][T17310] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[1138.917195][T17310] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[1138.917377][T17310] ? find_held_lock (kernel/locking/lockdep.c:5339)
[1138.917557][T17310] ? __lock_release (kernel/locking/lockdep.c:5525)
[1138.917735][T17310] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[1138.917918][T17310] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[1138.918097][T17310] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[1138.918285][T17310] __sys_sendmsg (net/socket.c:2680)
[1138.918466][T17310] ? __pfx___sys_sendmsg (net/socket.c:2665)
[1138.918646][T17310] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[1138.918876][T17310] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[1138.919057][T17310] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 1138.919283][T17310] RIP: 0033:0x7f321d7cb9a7
[ 1138.919470][T17310] 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)
[ 1138.920125][T17310] RSP: 002b:00007fff6bfe4168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 1138.920396][T17310] RAX: ffffffffffffffda RBX: 00007fff6bfe4890 RCX: 00007f321d7cb9a7
[ 1138.920668][T17310] RDX: 0000000000000000 RSI: 00007fff6bfe41d0 RDI: 0000000000000005
[ 1138.920937][T17310] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078
[ 1138.921205][T17310] R10: 00007f321d689ef8 R11: 0000000000000246 R12: 0000000000000002


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