======================================
| [ 17.077112][ T404] #0: ffffffff9d1e7a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink (net/core/rtnetlink.c:337 net/core/rtnetlink.c:4020)
| [ 17.077390][ T404] #1: ffffffff9d1d6630 ((netdev_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
| [   17.077763][  T404]
| [   17.077763][  T404] stack backtrace:
[   17.078314][  T404] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   17.078583][  T404] Call Trace:
[   17.078704][  T404]  <TASK>
[ 17.078784][ T404] dump_stack_lvl (lib/dump_stack.c:123)
[ 17.078954][ T404] print_deadlock_bug (kernel/locking/lockdep.c:3040)
[ 17.079107][ T404] validate_chain (kernel/locking/lockdep.c:3894)
[ 17.079262][ T404] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 17.079416][ T404] ? 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)
[ 17.079570][ T404] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 17.079687][ T404] __lock_acquire (kernel/locking/lockdep.c:5226)
[ 17.079841][ T404] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380)
[ 17.080011][ T404] lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 17.080170][ T404] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 17.080360][ T404] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 17.080513][ T404] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 17.080680][ T404] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 37))
[ 17.080848][ T404] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 17.081020][ T404] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 17.081227][ T404] down_read (./arch/x86/include/asm/preempt.h:79 kernel/locking/rwsem.c:1246 kernel/locking/rwsem.c:1261 kernel/locking/rwsem.c:1526)
[ 17.081357][ T404] ? blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 17.081562][ T404] ? __pfx_down_read (kernel/locking/rwsem.c:1522)
[ 17.081726][ T404] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 17.081909][ T404] blocking_notifier_call_chain (kernel/notifier.c:380 kernel/notifier.c:368)
[ 17.082074][ T404] dev_set_mtu_ext (./include/linux/notifier.h:207 net/core/dev.c:9101)
[ 17.082241][ T404] ? __pfx_dev_set_mtu_ext (net/core/dev.c:9087)
[ 17.082408][ T404] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4339 kernel/locking/lockdep.c:4406)
[ 17.082619][ T404] ? fib6_walk (net/ipv6/ip6_fib.c:2175)
[ 17.082787][ T404] ? __local_bh_enable_ip (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 kernel/softirq.c:394)
[ 17.082962][ T404] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 17.083131][ T404] dev_set_mtu (net/core/dev.c:9130)
[ 17.083258][ T404] ? __pfx_dev_set_mtu (net/core/dev.c:9125)
[ 17.083424][ T404] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 17.083595][ T404] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 17.083756][ T404] ? packet_notifier (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/packet/af_packet.c:4280)
[ 17.083924][ T404] br_mtu_auto_adjust (net/bridge/br_if.c:525) bridge
[ 17.084152][ T404] br_device_event (net/bridge/br.c:142) bridge
[ 17.084423][ T404] ? __pfx_br_device_event (net/bridge/br.c:29) bridge
[ 17.084636][ T404] ? packet_notifier (net/packet/af_packet.c:4282)
[ 17.084790][ T404] notifier_call_chain (kernel/notifier.c:85 (discriminator 2))
[ 17.084958][ T404] blocking_notifier_call_chain (kernel/notifier.c:381 kernel/notifier.c:368)
[ 17.085118][ T404] dev_set_mtu_ext (./include/linux/notifier.h:207 net/core/dev.c:9111)
[ 17.085276][ T404] ? __pfx_dev_set_mtu_ext (net/core/dev.c:9087)
[ 17.085428][ T404] ? __pfx_stack_trace_consume_entry (kernel/stacktrace.c:83)
[ 17.085620][ T404] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860)
[ 17.085776][ T404] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 17.085904][ T404] do_setlink.constprop.0 (net/core/rtnetlink.c:3081)
[ 17.086062][ T404] ? __pfx_do_setlink.constprop.0 (net/core/rtnetlink.c:2999)
[ 17.086256][ T404] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
[ 17.086421][ T404] ? rtnl_newlink (net/core/rtnetlink.c:337 net/core/rtnetlink.c:4020)
[ 17.086605][ T404] ? rtnl_newlink (./include/linux/slab.h:901 net/core/rtnetlink.c:3921)
[ 17.086786][ T404] ? rtnetlink_rcv_msg (net/core/rtnetlink.c:6911)
[ 17.086984][ T404] ? __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)
[ 17.087202][ T404] ? __pfx___mutex_trylock_common (kernel/locking/mutex.c:79)
[ 17.087498][ T404] ? lock_acquire (kernel/locking/lockdep.c:5822)
[ 17.087749][ T404] ? trace_contention_end (./include/trace/events/lock.h:122 (discriminator 37))
[ 17.087979][ T404] ? __mutex_lock (./arch/x86/include/asm/preempt.h:94 kernel/locking/mutex.c:595 kernel/locking/mutex.c:735)
[ 17.088224][ T404] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114)
[ 17.088461][ T404] ? rtnl_newlink (net/core/rtnetlink.c:337 net/core/rtnetlink.c:4020)
[ 17.088700][ T404] ? __pfx___mutex_lock (kernel/locking/mutex.c:734)
[ 17.088945][ T404] ? __rtnl_newlink (net/core/rtnetlink.c:3871)
[ 17.089188][ T404] rtnl_newlink (net/core/rtnetlink.c:345 net/core/rtnetlink.c:4022)
[ 17.089432][ T404] ? __pfx_rtnl_newlink (net/core/rtnetlink.c:3912)
[ 17.089680][ T404] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 17.089923][ T404] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 17.090164][ T404] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 17.090410][ T404] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6909)
[ 17.090657][ T404] ? __pfx_rtnl_newlink (net/core/rtnetlink.c:3912)
[ 17.090894][ T404] rtnetlink_rcv_msg (net/core/rtnetlink.c:6911)
[ 17.091093][ T404] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 17.091249][ T404] ? 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)
[ 17.091402][ T404] ? mark_lock (kernel/locking/lockdep.c:4727 (discriminator 3))
[ 17.091519][ T404] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 17.091703][ T404] netlink_rcv_skb (net/netlink/af_netlink.c:2543)
[ 17.091889][ T404] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6814)
[ 17.092042][ T404] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2520)
[ 17.092198][ T404] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340)
[ 17.092357][ T404] ? 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)
[ 17.092508][ T404] netlink_unicast (net/netlink/af_netlink.c:1322 net/netlink/af_netlink.c:1348)
[ 17.092657][ T404] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1333)
[ 17.092809][ T404] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 17.093031][ T404] netlink_sendmsg (net/netlink/af_netlink.c:1892)
[ 17.093264][ T404] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1811)
[ 17.093509][ T404] ____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2594)
[ 17.093764][ T404] ? __pfx_____sys_sendmsg (net/socket.c:2540)
[ 17.094015][ T404] ? __pfx_copy_msghdr_from_user (net/socket.c:2520)
[ 17.094322][ T404] ___sys_sendmsg (net/socket.c:2650)
[ 17.094566][ T404] ? __pfx____sys_sendmsg (net/socket.c:2637)
[ 17.094805][ T404] ? kasan_save_stack (mm/kasan/common.c:49)
[ 17.095028][ T404] ? kasan_save_stack (mm/kasan/common.c:48)
[ 17.095254][ T404] ? __kasan_record_aux_stack (mm/kasan/generic.c:544)
[ 17.095485][ T404] ? __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)
[ 17.095764][ T404] ? __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539)
[ 17.095990][ T404] ? do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 17.096215][ T404] ? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[ 17.096493][ T404] ? __lock_acquire (kernel/locking/lockdep.c:5226)
[ 17.096744][ T404] ? find_held_lock (kernel/locking/lockdep.c:5339)
[ 17.096993][ T404] ? __lock_release (kernel/locking/lockdep.c:5525)
[ 17.097234][ T404] ? __virt_addr_valid (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 ./include/linux/mmzone.h:2058 arch/x86/mm/physaddr.c:65)
[ 17.097479][ T404] ? __pfx___lock_release (kernel/locking/lockdep.c:5501)
[ 17.097715][ T404] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5814)
[ 17.097944][ T404] __sys_sendmsg (net/socket.c:2680)
[ 17.098163][ T404] ? __pfx___sys_sendmsg (net/socket.c:2665)
[ 17.098382][ T404] ? __pfx_slab_free_after_rcu_debug (mm/slub.c:4643)
[ 17.098683][ T404] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 17.098915][ T404] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   17.099192][  T404] RIP: 0033:0x7f77920859a7
[ 17.099442][ T404] 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)
[   17.100250][  T404] RSP: 002b:00007fffe47a2f18 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[   17.100609][  T404] RAX: ffffffffffffffda RBX: 00007fffe47a3640 RCX: 00007f77920859a7
[   17.100971][  T404] RDX: 0000000000000000 RSI: 00007fffe47a2f80 RDI: 0000000000000005
[   17.101331][  T404] RBP: 0000000000000004 R08: 0000000000000003 R09: 0000000000000078
[   17.101670][  T404] R10: 00007f7791f43ef8 R11: 0000000000000246 R12: 0000000000000004


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