======================================
| [ 17.292782][ T401] #0: ffffffff871e7a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink (net/core/rtnetlink.c:328 net/core/rtnetlink.c:4011)
| [ 17.293061][ T401] #1: ffffffff871d6630 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [   17.293374][  T401]
| [   17.293374][  T401] stack backtrace:
[   17.293816][  T401] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   17.294027][  T401] Call Trace:
[   17.294144][  T401]  <TASK>
[ 17.294229][ T401] dump_stack_lvl (lib/dump_stack.c:123)
[ 17.294397][ T401] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[ 17.294556][ T401] validate_chain (kernel/locking/lockdep.c:3894)
[ 17.294709][ T401] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 17.294887][ T401] ? 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)
[ 17.295041][ T401] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 17.295159][ T401] __lock_acquire (kernel/locking/lockdep.c:5226)
[ 17.295314][ T401] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380)
[ 17.295471][ T401] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 17.295632][ T401] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 17.295834][ T401] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 17.295986][ T401] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 17.296139][ T401] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 17.296292][ T401] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 17.296444][ T401] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 17.296639][ T401] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[ 17.296768][ T401] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 17.296960][ T401] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[ 17.297114][ T401] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 17.297272][ T401] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 17.297429][ T401] dev_set_mtu_ext (./include/linux/notifier.h:207 net/core/dev.c:9101)
[ 17.297585][ T401] ? __pfx_dev_set_mtu_ext (net/core/dev.c:9087)
[ 17.297739][ T401] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4339 kernel/locking/lockdep.c:4406)
[ 17.297945][ T401] ? fib6_walk (net/ipv6/ip6_fib.c:2175)
[ 17.298107][ T401] ? __local_bh_enable_ip (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 kernel/softirq.c:394)
[ 17.298265][ T401] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 17.298419][ T401] dev_set_mtu (net/core/dev.c:9130)
[ 17.298537][ T401] ? __pfx_dev_set_mtu (net/core/dev.c:9125)
[ 17.298690][ T401] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 17.298852][ T401] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 17.299013][ T401] ? packet_notifier (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/packet/af_packet.c:4280)
[ 17.299196][ T401] br_mtu_auto_adjust (net/bridge/br_if.c:525) bridge
[ 17.299423][ T401] br_device_event (net/bridge/br.c:142) bridge
[ 17.299604][ T401] ? __pfx_br_device_event (net/bridge/br.c:29) bridge
[ 17.299834][ T401] ? packet_notifier (net/packet/af_packet.c:4282)
[ 17.299994][ T401] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[ 17.300152][ T401] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[ 17.300317][ T401] dev_set_mtu_ext (./include/linux/notifier.h:207 net/core/dev.c:9111)
[ 17.300473][ T401] ? __pfx_dev_set_mtu_ext (net/core/dev.c:9087)
[ 17.300629][ T401] ? __pfx_stack_trace_consume_entry (kernel/stacktrace.c:83)
[ 17.300830][ T401] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 17.300984][ T401] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 17.301103][ T401] do_setlink.constprop.0 (net/core/rtnetlink.c:3072)
[ 17.301260][ T401] ? __pfx_do_setlink.constprop.0 (net/core/rtnetlink.c:2990)
[ 17.301458][ T401] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 17.301612][ T401] ? rtnl_newlink (net/core/rtnetlink.c:328 net/core/rtnetlink.c:4011)
[ 17.301768][ T401] ? rtnl_newlink (./include/linux/slab.h:901 net/core/rtnetlink.c:3912)
[ 17.301931][ T401] ? rtnetlink_rcv_msg (net/core/rtnetlink.c:6902)
[ 17.302087][ T401] ? __mutex_trylock_common (./arch/x86/include/asm/atomic64_64.h:101 ./include/linux/atomic/atomic-arch-fallback.h:4296 ./include/linux/atomic/atomic-long.h:1482 ./include/linux/atomic/atomic-instrumented.h:4458 kernel/locking/mutex.c:104)
[ 17.302241][ T401] ? __pfx___mutex_trylock_common (kernel/locking/mutex.c:79)
[ 17.302443][ T401] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 17.302689][ T401] ? trace_contention_end (./include/trace/events/lock.h:122 (discriminator 37))
[ 17.302893][ T401] ? __mutex_lock (./arch/x86/include/asm/preempt.h:94 kernel/locking/mutex.c:595 kernel/locking/mutex.c:735)
[ 17.303051][ T401] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114)
[ 17.303214][ T401] ? rtnl_newlink (net/core/rtnetlink.c:328 net/core/rtnetlink.c:4011)
[ 17.303368][ T401] ? __pfx___mutex_lock (kernel/locking/mutex.c:734)
[ 17.303523][ T401] ? __rtnl_newlink (net/core/rtnetlink.c:3862)
[ 17.303680][ T401] rtnl_newlink (net/core/rtnetlink.c:336 net/core/rtnetlink.c:4013)
[ 17.303851][ T401] ? __pfx_rtnl_newlink (net/core/rtnetlink.c:3903)
[ 17.304014][ T401] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 17.304172][ T401] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 17.304323][ T401] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 17.304476][ T401] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6900)
[ 17.304626][ T401] ? __pfx_rtnl_newlink (net/core/rtnetlink.c:3903)
[ 17.304783][ T401] rtnetlink_rcv_msg (net/core/rtnetlink.c:6902)
[ 17.304933][ T401] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6805)
[ 17.305095][ T401] ? 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)
[ 17.305243][ T401] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 17.305359][ T401] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 17.305510][ T401] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[ 17.305662][ T401] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6805)
[ 17.305820][ T401] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[ 17.305973][ T401] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[ 17.306132][ T401] ? 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)
[ 17.306284][ T401] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[ 17.306435][ T401] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[ 17.306584][ T401] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 17.306736][ T401] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 17.306895][ T401] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[ 17.307051][ T401] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 17.307208][ T401] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[ 17.307357][ T401] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[ 17.307548][ T401] ___sys_sendmsg (net/socket.c:2650)
[ 17.307701][ T401] ? __pfx____sys_sendmsg (net/socket.c:2637)
[ 17.307862][ T401] ? kasan_save_stack (mm/kasan/common.c:49)
[ 17.308014][ T401] ? kasan_save_stack (mm/kasan/common.c:48)
[ 17.308167][ T401] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[ 17.308323][ T401] ? __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)
[ 17.308512][ T401] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[ 17.308661][ T401] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 17.308819][ T401] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 17.309007][ T401] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 17.309161][ T401] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 17.309311][ T401] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 17.309460][ T401] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[ 17.309619][ T401] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 17.309773][ T401] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 17.309924][ T401] __sys_sendmsg (net/socket.c:2680)
[ 17.310078][ T401] ? __pfx___sys_sendmsg (net/socket.c:2665)
[ 17.310226][ T401] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[ 17.310417][ T401] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 17.310571][ T401] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   17.310769][  T401] RIP: 0033:0x7f5c5a5c79a7
[ 17.310944][ T401] 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)
[   17.311619][  T401] RSP: 002b:00007ffffc46c1f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[   17.311993][  T401] RAX: ffffffffffffffda RBX: 00007ffffc46c920 RCX: 00007f5c5a5c79a7
[   17.312344][  T401] RDX: 0000000000000000 RSI: 00007ffffc46c260 RDI: 0000000000000005
[   17.312718][  T401] RBP: 0000000000000004 R08: 0000000000000003 R09: 0000000000000078
[   17.313078][  T401] R10: 00007f5c5a485ef8 R11: 0000000000000246 R12: 0000000000000004


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