======================================
| [ 44.232752][ T1017] #1: ffffffffb2607e88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink (net/core/rtnetlink.c:337 net/core/rtnetlink.c:4020)
| [ 44.233011][ T1017] #2: ffffffffb25f6a70 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [   44.233314][ T1017]
| [   44.233314][ T1017] stack backtrace:
[   44.233713][ T1017] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   44.233894][ T1017] Call Trace:
[   44.234008][ T1017]  <TASK>
[ 44.234085][ T1017] dump_stack_lvl (lib/dump_stack.c:123)
[ 44.234245][ T1017] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[ 44.234396][ T1017] validate_chain (kernel/locking/lockdep.c:3894)
[ 44.234543][ T1017] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 44.234692][ T1017] ? 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)
[ 44.234838][ T1017] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 44.234951][ T1017] __lock_acquire (kernel/locking/lockdep.c:5226)
[ 44.235099][ T1017] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 44.235244][ T1017] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 44.235429][ T1017] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 44.235576][ T1017] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 44.235723][ T1017] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 44.235868][ T1017] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 44.236051][ T1017] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[ 44.236164][ T1017] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 44.236348][ T1017] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[ 44.236497][ T1017] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 44.236645][ T1017] netdev_update_features (net/core/dev.c:10314)
[ 44.236792][ T1017] ? __pfx_netdev_update_features (net/core/dev.c:10311)
[ 44.236974][ T1017] vlan_device_event (net/8021q/vlan.c:430 (discriminator 2))
[ 44.237123][ T1017] ? __pfx_vlan_device_event (net/8021q/vlan.c:362)
[ 44.237272][ T1017] ? __pfx_br_device_event (net/bridge/br.c:29)
[ 44.237425][ T1017] ? packet_notifier (net/packet/af_packet.c:4282)
[ 44.237580][ T1017] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[ 44.237729][ T1017] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[ 44.237879][ T1017] netdev_update_features (net/core/dev.c:10314)
[ 44.238024][ T1017] ? __pfx_netdev_update_features (net/core/dev.c:10311)
[ 44.238206][ T1017] br_add_if (net/bridge/br_if.c:657)
[ 44.238321][ T1017] ? rtnl_is_locked (net/core/rtnetlink.c:163)
[ 44.238473][ T1017] ? netdev_master_upper_dev_get (net/core/dev.c:7230)
[ 44.238657][ T1017] rtnl_newlink_create (net/core/rtnetlink.c:3813)
[ 44.238805][ T1017] ? __pfx_rtnl_newlink_create (net/core/rtnetlink.c:3762)
[ 44.238952][ T1017] ? rtnl_newlink (net/core/rtnetlink.c:337 net/core/rtnetlink.c:4020)
[ 44.239102][ T1017] ? __pfx___mutex_lock (kernel/locking/mutex.c:734)
[ 44.239248][ T1017] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 44.239398][ T1017] __rtnl_newlink (net/core/rtnetlink.c:3906)
[ 44.239549][ T1017] rtnl_newlink (net/core/rtnetlink.c:345 net/core/rtnetlink.c:4022)
[ 44.239698][ T1017] ? __pfx_rtnl_newlink (net/core/rtnetlink.c:3912)
[ 44.239845][ T1017] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 44.239991][ T1017] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 44.240141][ T1017] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[ 44.240289][ T1017] ? __pfx_rtnl_newlink (net/core/rtnetlink.c:3912)
[ 44.240434][ T1017] rtnetlink_rcv_msg (net/core/rtnetlink.c:6911)
[ 44.240582][ T1017] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 44.240729][ T1017] ? 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)
[ 44.240874][ T1017] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 44.240986][ T1017] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 44.241133][ T1017] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[ 44.241281][ T1017] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 44.241429][ T1017] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[ 44.241580][ T1017] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[ 44.241730][ T1017] ? 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)
[ 44.241877][ T1017] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[ 44.242027][ T1017] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[ 44.242174][ T1017] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 44.242321][ T1017] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 44.242471][ T1017] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[ 44.242622][ T1017] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 44.242773][ T1017] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[ 44.242918][ T1017] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[ 44.243105][ T1017] ___sys_sendmsg (net/socket.c:2650)
[ 44.243252][ T1017] ? __pfx____sys_sendmsg (net/socket.c:2637)
[ 44.243398][ T1017] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 44.243544][ T1017] ? __pfx_handle_pte_fault (mm/memory.c:5758)
[ 44.243696][ T1017] ? __handle_mm_fault (mm/memory.c:5944)
[ 44.243845][ T1017] ? __pfx___handle_mm_fault (mm/memory.c:5853)
[ 44.243989][ T1017] ? mt_find (lib/maple_tree.c:6949)
[ 44.244102][ T1017] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 44.244247][ T1017] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 44.244393][ T1017] ? do_user_addr_fault (./include/linux/mmap_lock.h:172 arch/x86/mm/fault.c:1417)
[ 44.244542][ T1017] __sys_sendmsg (net/socket.c:2680)
[ 44.244688][ T1017] ? __pfx___sys_sendmsg (net/socket.c:2665)
[ 44.244838][ T1017] ? do_user_addr_fault (./include/linux/mmap_lock.h:172 arch/x86/mm/fault.c:1417)
[ 44.244985][ T1017] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 44.245132][ T1017] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   44.245312][ T1017] RIP: 0033:0x7fb4981e99a7
[ 44.245465][ T1017] 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)
[   44.245977][ T1017] RSP: 002b:00007fff08fda998 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[   44.246197][ T1017] RAX: ffffffffffffffda RBX: 00007fff08fdb0d0 RCX: 00007fb4981e99a7
[   44.246422][ T1017] RDX: 0000000000000000 RSI: 00007fff08fdaa00 RDI: 0000000000000005
[   44.246641][ T1017] RBP: 0000000000000006 R08: 000000000000006c R09: 0000000000000000
[   44.246865][ T1017] R10: 00007fb498238ac0 R11: 0000000000000246 R12: 00007fff08fdb108


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