======================================
| [   31.709150][  T244] 1 lock held by connect-deny_ip/244:
| [ 31.709368][ T244] #0: ffff888004f32a58 (sk_lock-AF_INET){+.+.}-{0:0}, at: do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
| [   31.709689][  T244]
| [   31.709689][  T244] stack backtrace:
[   31.710252][  T244] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   31.710650][  T244] Call Trace:
[   31.710799][  T244]  <TASK>
[ 31.710897][ T244] dump_stack_lvl (lib/dump_stack.c:123) 
[ 31.711068][ T244] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 31.711251][ T244] tcp_ao_copy_mkts_to_user (net/ipv4/tcp_ao.c:2232 (discriminator 7)) 
[ 31.711424][ T244] ? mark_held_locks (kernel/locking/lockdep.c:4321) 
[ 31.711593][ T244] ? __pfx_tcp_ao_copy_mkts_to_user (net/ipv4/tcp_ao.c:2106) 
[ 31.711800][ T244] ? stack_depot_save_flags (lib/stackdepot.c:664) 
[ 31.712005][ T244] ? kasan_save_stack (mm/kasan/common.c:48) 
[ 31.712187][ T244] ? kasan_save_track (./arch/x86/include/asm/current.h:49 mm/kasan/common.c:60 mm/kasan/common.c:69) 
[ 31.712498][ T244] ? kasan_save_free_info (mm/kasan/generic.c:582) 
[ 31.712780][ T244] ? __kasan_slab_free (mm/kasan/common.c:271) 
[ 31.713057][ T244] ? kfree (mm/slub.c:4579 mm/slub.c:4727) 
[ 31.713274][ T244] ? tcp_ao_parse_crypto (./include/net/tcp_ao.h:67 net/ipv4/tcp_ao.c:1436) 
[ 31.713616][ T244] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 31.713926][ T244] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5827) 
[ 31.714144][ T244] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 31.714359][ T244] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 31.714558][ T244] ? do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 31.714741][ T244] ? 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) 
[ 31.714908][ T244] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 31.715043][ T244] ? do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 31.715206][ T244] do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 31.715408][ T244] ? __pfx_do_tcp_getsockopt (net/ipv4/tcp.c:4300) 
[ 31.715567][ T244] ? tcp_ao_add_cmd (net/ipv4/tcp_ao.c:1737) 
[ 31.715750][ T244] ? release_sock (net/core/sock.c:3630) 
[ 31.715913][ T244] ? reacquire_held_locks (kernel/locking/lockdep.c:5350) 
[ 31.716070][ T244] ? release_sock (net/core/sock.c:3630) 
[ 31.716244][ T244] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 31.716411][ T244] ? validate_chain (kernel/locking/lockdep.c:3797 kernel/locking/lockdep.c:3817 kernel/locking/lockdep.c:3872) 
[ 31.716577][ T244] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 31.716744][ T244] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860) 
[ 31.716905][ T244] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860) 
[ 31.717065][ T244] ? 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) 
[ 31.717226][ T244] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 31.717438][ T244] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 31.717730][ T244] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 31.718002][ T244] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 31.718280][ T244] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 31.718489][ T244] ? __pfx___lock_release (kernel/locking/lockdep.c:5477) 
[ 31.718646][ T244] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 31.718813][ T244] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 31.718982][ T244] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 31.719143][ T244] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 31.719332][ T244] tcp_getsockopt (net/ipv4/tcp.c:4673 net/ipv4/tcp.c:4664) 
[ 31.719503][ T244] do_sock_getsockopt (net/socket.c:2396) 
[ 31.719663][ T244] ? __fget_files (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 fs/file.c:1006) 
[ 31.719828][ T244] ? __pfx_do_sock_getsockopt (net/socket.c:2374) 
[ 31.719997][ T244] ? fdget (fs/file.c:1121 fs/file.c:1128) 
[ 31.720122][ T244] __sys_getsockopt (./include/linux/file.h:35 net/socket.c:2428) 
[ 31.720286][ T244] ? __pfx___sys_getsockopt (net/socket.c:2415) 
[ 31.720453][ T244] ? __pfx_task_work_run (kernel/task_work.c:207) 
[ 31.720626][ T244] __x64_sys_getsockopt (net/socket.c:2432) 
[ 31.720819][ T244] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 31.721037][ T244] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 31.721215][ T244] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   31.721432][  T244] RIP: 0033:0x7fd424f3a46e
[ 31.721601][ T244] 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
[   31.722170][  T244] RSP: 002b:00007fd41fffe998 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
[   31.722440][  T244] RAX: ffffffffffffffda RBX: 00007fd41fffec60 RCX: 00007fd424f3a46e
[   31.722696][  T244] RDX: 0000000000000029 RSI: 0000000000000006 RDI: 000000000000000a
[   31.722956][  T244] RBP: 00007fd41fffe9b0 R08: 00007fd41fffe9ac R09: 0000000000000064
[   31.723194][  T244] R10: 00007fd41fffe9b0 R11: 0000000000000246 R12: 000000000000000a
[   31.723442][  T244] R13: 0000000000000064 R14: 0000000000000020 R15: 0000000000000064
| [   31.730046][  T244] 1 lock held by connect-deny_ip/244:
| [ 31.730210][ T244] #0: ffff888004f32a58 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_stream_connect (net/ipv4/af_inet.c:748) 
| [   31.730524][  T244]
| [   31.730524][  T244] stack backtrace:
[   31.731010][  T244] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   31.731396][  T244] Call Trace:
[   31.731522][  T244]  <TASK>
[ 31.731611][ T244] dump_stack_lvl (lib/dump_stack.c:123) 
[ 31.731815][ T244] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 31.731984][ T244] __tcp_ao_do_lookup.part.0 (net/ipv4/tcp_ao.c:208) 
[ 31.732158][ T244] tcp_v4_ao_lookup (net/ipv4/tcp_ao.c:200 net/ipv4/tcp_ao.c:222 net/ipv4/tcp_ao.c:720) 
[ 31.732328][ T244] tcp_connect (net/ipv4/tcp_output.c:4114) 
[ 31.732500][ T244] tcp_v4_connect (net/ipv4/tcp_ipv4.c:342) 
[ 31.732680][ T244] ? __pfx_tcp_v4_connect (net/ipv4/tcp_ipv4.c:220) 
[ 31.732862][ T244] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 31.733006][ T244] __inet_stream_connect (net/ipv4/af_inet.c:677) 
[ 31.733190][ T244] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 31.733398][ T244] inet_stream_connect (net/ipv4/af_inet.c:749) 
[ 31.733564][ T244] __sys_connect (net/socket.c:2071 net/socket.c:2088) 
[ 31.733730][ T244] ? __pfx___sys_connect (net/socket.c:2078) 
[ 31.733920][ T244] ? do_fcntl (fs/fcntl.c:473) 
[ 31.734085][ T244] ? __pfx_do_fcntl (fs/fcntl.c:443) 
[ 31.734259][ T244] ? __fget_files (fs/file.c:1009) 
[ 31.734458][ T244] __x64_sys_connect (net/socket.c:2095) 
[ 31.734703][ T244] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 31.734872][ T244] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   31.735072][  T244] RIP: 0033:0x7fd424f3a40b
[ 31.735244][ T244] 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
[   31.735810][  T244] RSP: 002b:00007fd41fffeae0 EFLAGS: 00000293 ORIG_RAX: 000000000000002a
[   31.736063][  T244] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00007fd424f3a40b
[   31.736309][  T244] RDX: 0000000000000010 RSI: 00007fd41fffec60 RDI: 000000000000000a
[   31.736557][  T244] RBP: 000000000000000a R08: 0000000000000000 R09: 0000000000414460
[   31.736806][  T244] R10: 00007fd424df2598 R11: 0000000000000293 R12: 000000000040eb20
[   31.737049][  T244] R13: 0000000000000001 R14: 00007fd41fffec60 R15: 00007fd41fffec60
| [   39.857730][  T244] 1 lock held by connect-deny_ip/244:
| [ 39.858061][ T244] #0: ffff888005239d18 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_stream_connect (net/ipv4/af_inet.c:748) 
| [   39.858517][  T244]
| [   39.858517][  T244] stack backtrace:
[   39.859283][  T244] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   39.859839][  T244] Call Trace:
[   39.860032][  T244]  <TASK>
[ 39.860178][ T244] dump_stack_lvl (lib/dump_stack.c:123) 
[ 39.860443][ T244] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 39.860727][ T244] tcp_ao_finish_connect (net/ipv4/tcp_ao.c:1183 (discriminator 7)) 
[ 39.861027][ T244] tcp_finish_connect (net/ipv4/tcp_input.c:6340) 
[ 39.861287][ T244] tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6576) 
[ 39.861626][ T244] ? 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) 
[ 39.861890][ T244] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 39.862095][ T244] ? __pfx_tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6455) 
[ 39.862432][ T244] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 39.862753][ T244] ? kvm_clock_get_cycles (./arch/x86/include/asm/preempt.h:94 arch/x86/kernel/kvmclock.c:80 arch/x86/kernel/kvmclock.c:86) 
[ 39.863024][ T244] ? 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)) 
[ 39.863222][ T244] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 39.863480][ T244] tcp_rcv_state_process (net/ipv4/tcp_input.c:6796) 
[ 39.863738][ T244] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 39.863976][ T244] ? __release_sock (./include/net/sock.h:1121 net/core/sock.c:3077) 
[ 39.864238][ T244] ? __pfx_tcp_rcv_state_process (net/ipv4/tcp_input.c:6751) 
[ 39.864583][ T244] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 39.864796][ T244] tcp_v4_do_rcv (net/ipv4/tcp_ipv4.c:1945) 
[ 39.865060][ T244] __release_sock (./include/net/sock.h:1121 net/core/sock.c:3077) 
[ 39.865342][ T244] release_sock (net/core/sock.c:3633) 
[ 39.865600][ T244] inet_stream_connect (net/ipv4/af_inet.c:751) 
[ 39.865860][ T244] __sys_connect (net/socket.c:2071 net/socket.c:2088) 
[ 39.866135][ T244] ? __pfx___sys_connect (net/socket.c:2078) 
[ 39.866390][ T244] ? do_fcntl (fs/fcntl.c:473) 
[ 39.866584][ T244] ? __pfx_do_fcntl (fs/fcntl.c:443) 
[ 39.866840][ T244] ? __fget_files (fs/file.c:1009) 
[ 39.867122][ T244] __x64_sys_connect (net/socket.c:2095) 
[ 39.867378][ T244] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 39.867653][ T244] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   39.867968][  T244] RIP: 0033:0x7fd424f3a40b
[ 39.868261][ T244] 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
[   39.869152][  T244] RSP: 002b:00007fd41fffeae0 EFLAGS: 00000293 ORIG_RAX: 000000000000002a
[   39.869547][  T244] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00007fd424f3a40b
[   39.869932][  T244] RDX: 0000000000000010 RSI: 00007fd41fffec60 RDI: 0000000000000009
[   39.870314][  T244] RBP: 0000000000000009 R08: 0000000000000000 R09: 00000000ffffffff
[   39.870707][  T244] R10: 000000000040eb20 R11: 0000000000000293 R12: 000000000040eb20


Finger prints:
lockdep_rcu_suspicious:tcp_v4_ao_lookup:tcp_connect:tcp_v4_connect:__inet_stream_connect
lockdep_rcu_suspicious:tcp_ao_copy_mkts_to_user:do_tcp_getsockopt:tcp_getsockopt:do_sock_getsockopt
lockdep_rcu_suspicious:tcp_ao_finish_connect:tcp_finish_connect:tcp_rcv_synsent_state_process:tcp_rcv_state_process