======================================
| [ 99.590077][ T743] #0: ffffffff89fe7a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink (net/core/rtnetlink.c:3521)
| [ 99.590495][ T743] #1: ffffffff89fd6630 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [   99.590968][  T743]
| [   99.590968][  T743] stack backtrace:
[   99.591589][  T743] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   99.591867][  T743] Call Trace:
[   99.592039][  T743]  <TASK>
[ 99.592160][ T743] dump_stack_lvl (lib/dump_stack.c:123)
[ 99.592395][ T743] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[ 99.592634][ T743] validate_chain (kernel/locking/lockdep.c:3894)
[ 99.592869][ T743] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 99.593098][ T743] ? 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)
[ 99.593334][ T743] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 99.593509][ T743] __lock_acquire (kernel/locking/lockdep.c:5226)
[ 99.593743][ T743] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 99.593974][ T743] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 99.594260][ T743] ? netconsole_process_cleanups_core (drivers/net/netconsole.c:242 (discriminator 11))
[ 99.594555][ T743] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 99.594790][ T743] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 99.595003][ T743] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 99.595219][ T743] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 99.595493][ T743] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[ 99.595654][ T743] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 99.595839][ T743] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[ 99.596042][ T743] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 99.596236][ T743] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[ 99.596443][ T743] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 99.596682][ T743] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 99.596911][ T743] __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))
[ 99.597138][ T743] ? __pfx___netdev_upper_dev_unlink (net/core/dev.c:8151)
[ 99.597435][ T743] ? __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)
[ 99.597665][ T743] ? __pfx___mutex_unlock_slowpath (kernel/locking/mutex.c:890)
[ 99.597959][ T743] ? rtnl_is_locked (net/core/rtnetlink.c:163)
[ 99.598192][ T743] netdev_upper_dev_unlink (net/core/dev.c:8190)
[ 99.598419][ T743] ? __pfx_netdev_upper_dev_unlink (net/core/dev.c:8190)
[ 99.598701][ T743] ? netconsole_netdev_event (drivers/net/netconsole.c:1082)
[ 99.598931][ T743] ? 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)
[ 99.599167][ T743] ? rtnl_is_locked (net/core/rtnetlink.c:163)
[ 99.599393][ T743] ? netdev_master_upper_dev_get (net/core/dev.c:7230)
[ 99.599674][ T743] vrf_device_event (drivers/net/vrf.c:1110 drivers/net/vrf.c:1119 drivers/net/vrf.c:1804) vrf
[ 99.599910][ T743] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[ 99.600138][ T743] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[ 99.600371][ T743] unregister_netdevice_many_notify (net/core/dev.c:11575)
[ 99.600665][ T743] ? __pfx_unregister_netdevice_many_notify (net/core/dev.c:11516)
[ 99.600957][ T743] ? rtnl_dellink (net/core/rtnetlink.c:3521)
[ 99.601184][ T743] ? sock_def_readable (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/sock.c:3479)
[ 99.601414][ T743] ? __pfx___mutex_lock (kernel/locking/mutex.c:734)
[ 99.601644][ T743] ? rtnl_is_locked (net/core/rtnetlink.c:163)
[ 99.601869][ T743] ? unregister_netdevice_queue (net/core/dev.c:11501)
[ 99.602148][ T743] ? __pfx_unregister_netdevice_queue (net/core/dev.c:11500)
[ 99.602431][ T743] ? __nla_validate_parse (./include/net/netlink.h:1270 (discriminator 1) lib/nlattr.c:622 (discriminator 1))
[ 99.602667][ T743] rtnl_dellink (net/core/rtnetlink.c:3487 net/core/rtnetlink.c:3527)
[ 99.602895][ T743] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3493)
[ 99.603150][ T743] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 99.603379][ T743] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 99.603607][ T743] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[ 99.603831][ T743] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 99.604057][ T743] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 99.604295][ T743] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[ 99.604518][ T743] ? __pfx_rtnl_dellink (net/core/rtnetlink.c:3493)
[ 99.604745][ T743] rtnetlink_rcv_msg (net/core/rtnetlink.c:6911)
[ 99.604973][ T743] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 99.605199][ T743] ? 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)
[ 99.605421][ T743] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 99.605595][ T743] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 99.605827][ T743] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[ 99.606043][ T743] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 99.606236][ T743] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[ 99.606391][ T743] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[ 99.606537][ T743] ? 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)
[ 99.606684][ T743] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[ 99.606844][ T743] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[ 99.607050][ T743] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 99.607264][ T743] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 99.607486][ T743] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[ 99.607711][ T743] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 99.607938][ T743] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[ 99.608165][ T743] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[ 99.608454][ T743] ___sys_sendmsg (net/socket.c:2650)
[ 99.608686][ T743] ? __pfx____sys_sendmsg (net/socket.c:2637)
[ 99.608915][ T743] ? kasan_save_stack (mm/kasan/common.c:49)
[ 99.609142][ T743] ? kasan_save_stack (mm/kasan/common.c:48)
[ 99.609366][ T743] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[ 99.609592][ T743] ? __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)
[ 99.609861][ T743] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[ 99.610085][ T743] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 99.610310][ T743] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 99.610601][ T743] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 99.610833][ T743] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 99.611064][ T743] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 99.611288][ T743] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[ 99.611518][ T743] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 99.611739][ T743] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 99.611971][ T743] __sys_sendmsg (net/socket.c:2680)
[ 99.612204][ T743] ? __pfx___sys_sendmsg (net/socket.c:2665)
[ 99.612432][ T743] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[ 99.612723][ T743] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 99.612950][ T743] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   99.613232][  T743] RIP: 0033:0x7f2d58df29a7
[ 99.613472][ T743] 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)
[   99.614277][  T743] RSP: 002b:00007ffe770cec88 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[   99.614622][  T743] RAX: ffffffffffffffda RBX: 00007ffe770cf3b0 RCX: 00007f2d58df29a7
[   99.614961][  T743] RDX: 0000000000000000 RSI: 00007ffe770cecf0 RDI: 0000000000000005
[   99.615308][  T743] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078
[   99.615647][  T743] R10: 00007f2d58cb0ef8 R11: 0000000000000246 R12: 0000000000000002


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