======================================
| [   29.321469][  T234] 1 lock held by connect_ipv6/234:
| [ 29.321630][ T234] #0: ffff888005741e98 (sk_lock-AF_INET6){+.+.}-{0:0}, at: do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
| [   29.321965][  T234]
| [   29.321965][  T234] stack backtrace:
[   29.322446][  T234] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   29.322966][  T234] Call Trace:
[   29.323096][  T234]  <TASK>
[ 29.323186][ T234] dump_stack_lvl (lib/dump_stack.c:123) 
[ 29.323351][ T234] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 29.323521][ T234] tcp_ao_copy_mkts_to_user (net/ipv4/tcp_ao.c:2232 (discriminator 7)) 
[ 29.323682][ T234] ? mark_held_locks (kernel/locking/lockdep.c:4321) 
[ 29.323848][ T234] ? __pfx_tcp_ao_copy_mkts_to_user (net/ipv4/tcp_ao.c:2106) 
[ 29.324046][ T234] ? stack_depot_save_flags (lib/stackdepot.c:664) 
[ 29.324213][ T234] ? kasan_save_stack (mm/kasan/common.c:48) 
[ 29.324374][ T234] ? kasan_save_track (./arch/x86/include/asm/current.h:49 mm/kasan/common.c:60 mm/kasan/common.c:69) 
[ 29.324538][ T234] ? kfree (mm/slub.c:4579 mm/slub.c:4727) 
[ 29.324663][ T234] ? tcp_ao_parse_crypto (./include/net/tcp_ao.h:67 net/ipv4/tcp_ao.c:1436) 
[ 29.324854][ T234] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 29.325024][ T234] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5827) 
[ 29.325185][ T234] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 29.325348][ T234] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 29.325505][ T234] ? do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 29.325667][ T234] ? 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) 
[ 29.325828][ T234] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 29.325965][ T234] ? do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 29.326126][ T234] do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 29.326293][ T234] ? __pfx_do_tcp_getsockopt (net/ipv4/tcp.c:4300) 
[ 29.326459][ T234] ? tcp_ao_add_cmd (net/ipv4/tcp_ao.c:1737) 
[ 29.326635][ T234] ? release_sock (net/core/sock.c:3630) 
[ 29.326793][ T234] ? reacquire_held_locks (kernel/locking/lockdep.c:5350) 
[ 29.326951][ T234] ? release_sock (net/core/sock.c:3630) 
[ 29.327114][ T234] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 29.327273][ T234] ? validate_chain (kernel/locking/lockdep.c:3797 kernel/locking/lockdep.c:3817 kernel/locking/lockdep.c:3872) 
[ 29.327434][ T234] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 29.327596][ T234] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 29.327765][ T234] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860) 
[ 29.327927][ T234] ? 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) 
[ 29.328090][ T234] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 29.328216][ T234] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 29.328389][ T234] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 29.328552][ T234] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 29.328708][ T234] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 29.328869][ T234] ? __pfx___lock_release (kernel/locking/lockdep.c:5477) 
[ 29.329025][ T234] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 29.329186][ T234] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 29.329344][ T234] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 29.329501][ T234] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 29.329662][ T234] tcp_getsockopt (net/ipv4/tcp.c:4673 net/ipv4/tcp.c:4664) 
[ 29.329827][ T234] do_sock_getsockopt (net/socket.c:2396) 
[ 29.329985][ T234] ? __fget_files (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 fs/file.c:1006) 
[ 29.330147][ T234] ? __pfx_do_sock_getsockopt (net/socket.c:2374) 
[ 29.330316][ T234] ? fdget (fs/file.c:1121 fs/file.c:1128) 
[ 29.330444][ T234] __sys_getsockopt (./include/linux/file.h:35 net/socket.c:2428) 
[ 29.330606][ T234] ? __sys_setsockopt (net/socket.c:2360) 
[ 29.330766][ T234] ? __pfx___sys_getsockopt (net/socket.c:2415) 
[ 29.330927][ T234] ? __pfx___sys_socket (net/socket.c:1712) 
[ 29.331095][ T234] __x64_sys_getsockopt (net/socket.c:2432) 
[ 29.331252][ T234] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 29.331448][ T234] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 29.331610][ T234] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   29.331808][  T234] RIP: 0033:0x7fe70261046e
[ 29.331981][ T234] Code: 1f 44 00 00 48 8b 15 91 99 0a 00 f7 d8 64 89 02 b8 ff ff ff ff eb b8 0f 1f 44 00 00 f3 0f 1e fa 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 0a c3 66 0f 1f 84 00 00 00 00 00 48 8b 15 59
All code
========
   0:	1f                   	(bad)
   1:	44 00 00             	add    %r8b,(%rax)
   4:	48 8b 15 91 99 0a 00 	mov    0xa9991(%rip),%rdx        # 0xa999c
   b:	f7 d8                	neg    %eax
   d:	64 89 02             	mov    %eax,%fs:(%rdx)
  10:	b8 ff ff ff ff       	mov    $0xffffffff,%eax
  15:	eb b8                	jmp    0xffffffffffffffcf
  17:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  1c:	f3 0f 1e fa          	endbr64
  20:	49 89 ca             	mov    %rcx,%r10
  23:	b8 37 00 00 00       	mov    $0x37,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 0a                	ja     0x3c
  32:	c3                   	ret
  33:	66 0f 1f 84 00 00 00 	nopw   0x0(%rax,%rax,1)
  3a:	00 00 
  3c:	48                   	rex.W
  3d:	8b                   	.byte 0x8b
  3e:	15                   	.byte 0x15
  3f:	59                   	pop    %rcx

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 0a                	ja     0x12
   8:	c3                   	ret
   9:	66 0f 1f 84 00 00 00 	nopw   0x0(%rax,%rax,1)
  10:	00 00 
  12:	48                   	rex.W
  13:	8b                   	.byte 0x8b
  14:	15                   	.byte 0x15
  15:	59                   	pop    %rcx
[   29.332534][  T234] RSP: 002b:00007ffe3a100e78 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
[   29.332775][  T234] RAX: ffffffffffffffda RBX: 00007ffe3a101130 RCX: 00007fe70261046e
[   29.333012][  T234] RDX: 0000000000000029 RSI: 0000000000000006 RDI: 0000000000000009
[   29.333255][  T234] RBP: 00007ffe3a100e90 R08: 00007ffe3a100e8c R09: 0000000000000064
[   29.333491][  T234] R10: 00007ffe3a100e90 R11: 0000000000000246 R12: 0000000000000009
[   29.333726][  T234] R13: 0000000000000064 R14: 0000000000000080 R15: 0000000000000064
| [   29.337561][  T241] 1 lock held by connect_ipv6/241:
| [ 29.337726][ T241] #0: ffff888005741098 (sk_lock-AF_INET6){+.+.}-{0:0}, at: inet_stream_connect (net/ipv4/af_inet.c:748) 
| [   29.338029][  T241]
| [   29.338029][  T241] stack backtrace:
[   29.338520][  T241] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   29.338883][  T241] Call Trace:
[   29.339011][  T241]  <TASK>
[ 29.339097][ T241] dump_stack_lvl (lib/dump_stack.c:123) 
[ 29.339262][ T241] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 29.339429][ T241] __tcp_ao_do_lookup.part.0 (net/ipv4/tcp_ao.c:208) 
[ 29.339600][ T241] tcp_ao_do_lookup (net/ipv4/tcp_ao.c:200 net/ipv4/tcp_ao.c:222) 
[ 29.339761][ T241] tcp_connect (net/ipv4/tcp_output.c:4114) 
[ 29.339924][ T241] ? rt6_get_cookie (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/net/ip6_fib.h:312) 
[ 29.340103][ T241] tcp_v6_connect (net/ipv6/tcp_ipv6.c:333) 
[ 29.340272][ T241] ? __pfx_tcp_v6_connect (net/ipv6/tcp_ipv6.c:137) 
[ 29.340437][ T241] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5827) 
[ 29.340599][ T241] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 29.340770][ T241] ? 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) 
[ 29.340933][ T241] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 29.341063][ T241] __inet_stream_connect (net/ipv4/af_inet.c:677) 
[ 29.341224][ T241] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 29.341428][ T241] inet_stream_connect (net/ipv4/af_inet.c:749) 
[ 29.341598][ T241] __sys_connect (net/socket.c:2071 net/socket.c:2088) 
[ 29.341762][ T241] ? __pfx___sys_connect (net/socket.c:2078) 
[ 29.341922][ T241] ? do_fcntl (fs/fcntl.c:473) 
[ 29.342052][ T241] ? __fget_files (fs/file.c:1009) 
[ 29.342228][ T241] __x64_sys_connect (net/socket.c:2095) 
[ 29.342392][ T241] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 29.342559][ T241] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   29.342760][  T241] RIP: 0033:0x7fe70261040b
[ 29.342934][ T241] Code: 83 ec 18 89 54 24 0c 48 89 34 24 89 7c 24 08 e8 eb c7 f4 ff 8b 54 24 0c 48 8b 34 24 41 89 c0 8b 7c 24 08 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 08 e8 41 c8 f4 ff 8b 44
All code
========
   0:	83 ec 18             	sub    $0x18,%esp
   3:	89 54 24 0c          	mov    %edx,0xc(%rsp)
   7:	48 89 34 24          	mov    %rsi,(%rsp)
   b:	89 7c 24 08          	mov    %edi,0x8(%rsp)
   f:	e8 eb c7 f4 ff       	call   0xfffffffffff4c7ff
  14:	8b 54 24 0c          	mov    0xc(%rsp),%edx
  18:	48 8b 34 24          	mov    (%rsp),%rsi
  1c:	41 89 c0             	mov    %eax,%r8d
  1f:	8b 7c 24 08          	mov    0x8(%rsp),%edi
  23:	b8 2a 00 00 00       	mov    $0x2a,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 35                	ja     0x67
  32:	44 89 c7             	mov    %r8d,%edi
  35:	89 44 24 08          	mov    %eax,0x8(%rsp)
  39:	e8 41 c8 f4 ff       	call   0xfffffffffff4c87f
  3e:	8b                   	.byte 0x8b
  3f:	44                   	rex.R

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 35                	ja     0x3d
   8:	44 89 c7             	mov    %r8d,%edi
   b:	89 44 24 08          	mov    %eax,0x8(%rsp)
   f:	e8 41 c8 f4 ff       	call   0xfffffffffff4c855
  14:	8b                   	.byte 0x8b
  15:	44                   	rex.R
[   29.343496][  T241] RSP: 002b:00007fe701cbbb70 EFLAGS: 00000293 ORIG_RAX: 000000000000002a
[   29.343741][  T241] RAX: ffffffffffffffda RBX: 000000000000001c RCX: 00007fe70261040b
[   29.343990][  T241] RDX: 000000000000001c RSI: 00007fe701cbbce0 RDI: 000000000000000b
[   29.344238][  T241] RBP: 000000000000000b R08: 0000000000000000 R09: 00000000ffffffff
[   29.344478][  T241] R10: 00007fe7024c8598 R11: 0000000000000293 R12: 000000000040cd28
[   29.344723][  T241] R13: 0000000000000005 R14: 00007fe701cbbce0 R15: 0000000000000000
| [   29.355884][  T241] 1 lock held by connect_ipv6/241:
| [ 29.356057][ T241] #0: ffff888005741098 (sk_lock-AF_INET6){+.+.}-{0:0}, at: inet_stream_connect (net/ipv4/af_inet.c:748) 
| [   29.356362][  T241]
| [   29.356362][  T241] stack backtrace:
[   29.356920][  T241] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   29.357282][  T241] Call Trace:
[   29.357409][  T241]  <TASK>
[ 29.357496][ T241] dump_stack_lvl (lib/dump_stack.c:123) 
[ 29.357665][ T241] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 29.357878][ T241] tcp_ao_finish_connect (net/ipv4/tcp_ao.c:1183 (discriminator 7)) 
[ 29.358064][ T241] tcp_finish_connect (net/ipv4/tcp_input.c:6340) 
[ 29.358234][ T241] tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6576) 
[ 29.358436][ T241] ? 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) 
[ 29.358605][ T241] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 29.358734][ T241] ? __pfx_tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6455) 
[ 29.358940][ T241] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 29.359142][ T241] ? kvm_clock_get_cycles (./arch/x86/include/asm/preempt.h:94 arch/x86/kernel/kvmclock.c:80 arch/x86/kernel/kvmclock.c:86) 
[ 29.359309][ T241] ? ktime_get (kernel/time/timekeeping.c:195 (discriminator 4) kernel/time/timekeeping.c:395 (discriminator 4) kernel/time/timekeeping.c:403 (discriminator 4) kernel/time/timekeeping.c:850 (discriminator 4)) 
[ 29.359444][ T241] tcp_rcv_state_process (net/ipv4/tcp_input.c:6796) 
[ 29.359607][ T241] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 29.359769][ T241] ? __release_sock (./include/net/sock.h:1121 net/core/sock.c:3077) 
[ 29.359934][ T241] ? __pfx_tcp_rcv_state_process (net/ipv4/tcp_input.c:6751) 
[ 29.360134][ T241] ? 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) 
[ 29.360297][ T241] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 29.360427][ T241] tcp_v6_do_rcv (net/ipv6/tcp_ipv6.c:1676) 
[ 29.360589][ T241] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 29.360795][ T241] __release_sock (net/core/sock.c:3079) 
[ 29.360964][ T241] release_sock (net/core/sock.c:3633) 
[ 29.361129][ T241] inet_stream_connect (net/ipv4/af_inet.c:751) 
[ 29.361295][ T241] __sys_connect (net/socket.c:2071 net/socket.c:2088) 
[ 29.361458][ T241] ? __pfx___sys_connect (net/socket.c:2078) 
[ 29.361619][ T241] ? do_fcntl (fs/fcntl.c:473) 
[ 29.361749][ T241] ? __fget_files (fs/file.c:1009) 
[ 29.361924][ T241] __x64_sys_connect (net/socket.c:2095) 
[ 29.362088][ T241] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 29.362256][ T241] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   29.362461][  T241] RIP: 0033:0x7fe70261040b
[ 29.362632][ T241] Code: 83 ec 18 89 54 24 0c 48 89 34 24 89 7c 24 08 e8 eb c7 f4 ff 8b 54 24 0c 48 8b 34 24 41 89 c0 8b 7c 24 08 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 08 e8 41 c8 f4 ff 8b 44
All code
========
   0:	83 ec 18             	sub    $0x18,%esp
   3:	89 54 24 0c          	mov    %edx,0xc(%rsp)
   7:	48 89 34 24          	mov    %rsi,(%rsp)
   b:	89 7c 24 08          	mov    %edi,0x8(%rsp)
   f:	e8 eb c7 f4 ff       	call   0xfffffffffff4c7ff
  14:	8b 54 24 0c          	mov    0xc(%rsp),%edx
  18:	48 8b 34 24          	mov    (%rsp),%rsi
  1c:	41 89 c0             	mov    %eax,%r8d
  1f:	8b 7c 24 08          	mov    0x8(%rsp),%edi
  23:	b8 2a 00 00 00       	mov    $0x2a,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 35                	ja     0x67
  32:	44 89 c7             	mov    %r8d,%edi
  35:	89 44 24 08          	mov    %eax,0x8(%rsp)
  39:	e8 41 c8 f4 ff       	call   0xfffffffffff4c87f
  3e:	8b                   	.byte 0x8b
  3f:	44                   	rex.R

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 35                	ja     0x3d
   8:	44 89 c7             	mov    %r8d,%edi
   b:	89 44 24 08          	mov    %eax,0x8(%rsp)
   f:	e8 41 c8 f4 ff       	call   0xfffffffffff4c855
  14:	8b                   	.byte 0x8b
  15:	44                   	rex.R
[   29.363203][  T241] RSP: 002b:00007fe701cbbb70 EFLAGS: 00000293 ORIG_RAX: 000000000000002a
[   29.363446][  T241] RAX: ffffffffffffffda RBX: 000000000000001c RCX: 00007fe70261040b
[   29.363691][  T241] RDX: 000000000000001c RSI: 00007fe701cbbce0 RDI: 000000000000000b
[   29.363937][  T241] RBP: 000000000000000b R08: 0000000000000000 R09: 00000000ffffffff
[   29.364180][  T241] R10: 00007fe7024c8598 R11: 0000000000000293 R12: 000000000040cd28


Finger prints:
lockdep_rcu_suspicious:tcp_ao_do_lookup:tcp_connect:tcp_v6_connect:__inet_stream_connect
lockdep_rcu_suspicious:tcp_ao_finish_connect:tcp_finish_connect:tcp_rcv_synsent_state_process:tcp_rcv_state_process
lockdep_rcu_suspicious:tcp_ao_copy_mkts_to_user:do_tcp_getsockopt:tcp_getsockopt:do_sock_getsockopt