======================================
| [   26.023517][  T242] 1 lock held by unsigned-md5_ip/242:
| [ 26.023680][ T242] #0: ffff888005a8aa58 (sk_lock-AF_INET){+.+.}-{0:0}, at: do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
| [   26.023990][  T242]
| [   26.023990][  T242] stack backtrace:
[   26.024464][  T242] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   26.024804][  T242] Call Trace:
[   26.024932][  T242]  <TASK>
[ 26.025016][ T242] dump_stack_lvl (lib/dump_stack.c:123) 
[ 26.025182][ T242] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 26.025356][ T242] tcp_ao_copy_mkts_to_user (net/ipv4/tcp_ao.c:2232 (discriminator 7)) 
[ 26.025516][ T242] ? mark_held_locks (kernel/locking/lockdep.c:4321) 
[ 26.025686][ T242] ? __pfx_tcp_ao_copy_mkts_to_user (net/ipv4/tcp_ao.c:2106) 
[ 26.025883][ T242] ? stack_depot_save_flags (lib/stackdepot.c:664) 
[ 26.026051][ T242] ? kasan_save_stack (mm/kasan/common.c:48) 
[ 26.026207][ T242] ? kasan_save_track (./arch/x86/include/asm/current.h:49 mm/kasan/common.c:60 mm/kasan/common.c:69) 
[ 26.026423][ T242] ? kasan_save_free_info (mm/kasan/generic.c:582) 
[ 26.026582][ T242] ? __kasan_slab_free (mm/kasan/common.c:271) 
[ 26.026744][ T242] ? kfree (mm/slub.c:4579 mm/slub.c:4727) 
[ 26.026868][ T242] ? tcp_ao_parse_crypto (./include/net/tcp_ao.h:67 net/ipv4/tcp_ao.c:1436) 
[ 26.027055][ T242] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 26.027229][ T242] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5827) 
[ 26.027389][ T242] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 26.027555][ T242] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 26.027710][ T242] ? do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 26.027875][ T242] ? 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) 
[ 26.028037][ T242] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.028171][ T242] ? do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 26.028335][ T242] do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 26.028504][ T242] ? __pfx_do_tcp_getsockopt (net/ipv4/tcp.c:4300) 
[ 26.028665][ T242] ? tcp_ao_add_cmd (net/ipv4/tcp_ao.c:1737) 
[ 26.028849][ T242] ? release_sock (net/core/sock.c:3630) 
[ 26.029005][ T242] ? reacquire_held_locks (kernel/locking/lockdep.c:5350) 
[ 26.029164][ T242] ? release_sock (net/core/sock.c:3630) 
[ 26.029323][ T242] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 26.029494][ T242] ? validate_chain (kernel/locking/lockdep.c:3797 kernel/locking/lockdep.c:3817 kernel/locking/lockdep.c:3872) 
[ 26.029649][ T242] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 26.029812][ T242] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860) 
[ 26.029970][ T242] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860) 
[ 26.030132][ T242] ? 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) 
[ 26.030289][ T242] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.030421][ T242] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 26.030592][ T242] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 26.030761][ T242] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 26.030918][ T242] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 26.031074][ T242] ? __pfx___lock_release (kernel/locking/lockdep.c:5477) 
[ 26.031231][ T242] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 26.031386][ T242] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 26.031545][ T242] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 26.031703][ T242] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 26.031866][ T242] tcp_getsockopt (net/ipv4/tcp.c:4673 net/ipv4/tcp.c:4664) 
[ 26.032026][ T242] do_sock_getsockopt (net/socket.c:2396) 
[ 26.032192][ T242] ? __fget_files (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 fs/file.c:1006) 
[ 26.032349][ T242] ? __pfx_do_sock_getsockopt (net/socket.c:2374) 
[ 26.032518][ T242] ? fdget (fs/file.c:1121 fs/file.c:1128) 
[ 26.032640][ T242] __sys_getsockopt (./include/linux/file.h:35 net/socket.c:2428) 
[ 26.032805][ T242] ? __pfx___sys_getsockopt (net/socket.c:2415) 
[ 26.032966][ T242] ? __pfx_task_work_run (kernel/task_work.c:207) 
[ 26.033128][ T242] ? do_user_addr_fault (./include/linux/rcupdate.h:882 ./include/linux/mm.h:729 arch/x86/mm/fault.c:1340) 
[ 26.033287][ T242] __x64_sys_getsockopt (net/socket.c:2432) 
[ 26.033445][ T242] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 26.033650][ T242] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 26.033839][ T242] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   26.034043][  T242] RIP: 0033:0x7f28d9a7a46e
[ 26.034206][ T242] 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
[   26.034759][  T242] RSP: 002b:00007f28d9125938 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
[   26.035000][  T242] RAX: ffffffffffffffda RBX: 00007f28d9125c00 RCX: 00007f28d9a7a46e
[   26.035238][  T242] RDX: 0000000000000029 RSI: 0000000000000006 RDI: 0000000000000009
[   26.035470][  T242] RBP: 00007f28d9125950 R08: 00007f28d912594c R09: 0000000000000064
[   26.035708][  T242] R10: 00007f28d9125950 R11: 0000000000000246 R12: 0000000000000009
[   26.035949][  T242] R13: 0000000000000064 R14: 0000000000000000 R15: 0000000000000064
| [   26.038291][  T242] 1 lock held by unsigned-md5_ip/242:
| [ 26.038451][ T242] #0: ffff888005a8aa58 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_stream_connect (net/ipv4/af_inet.c:748) 
| [   26.038743][  T242]
| [   26.038743][  T242] stack backtrace:
[   26.039210][  T242] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   26.039555][  T242] Call Trace:
[   26.039676][  T242]  <TASK>
[ 26.039760][ T242] dump_stack_lvl (lib/dump_stack.c:123) 
[ 26.039926][ T242] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 26.040088][ T242] __tcp_ao_do_lookup.part.0 (net/ipv4/tcp_ao.c:208) 
[ 26.040254][ T242] tcp_v4_ao_lookup (net/ipv4/tcp_ao.c:200 net/ipv4/tcp_ao.c:222 net/ipv4/tcp_ao.c:720) 
[ 26.040414][ T242] tcp_connect (net/ipv4/tcp_output.c:4114) 
[ 26.040581][ T242] tcp_v4_connect (net/ipv4/tcp_ipv4.c:342) 
[ 26.040753][ T242] ? __pfx_tcp_v4_connect (net/ipv4/tcp_ipv4.c:220) 
[ 26.040915][ T242] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.041040][ T242] __inet_stream_connect (net/ipv4/af_inet.c:677) 
[ 26.041199][ T242] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 26.041403][ T242] inet_stream_connect (net/ipv4/af_inet.c:749) 
[ 26.041565][ T242] __sys_connect (net/socket.c:2071 net/socket.c:2088) 
[ 26.041731][ T242] ? __pfx___sys_connect (net/socket.c:2078) 
[ 26.041889][ T242] ? do_fcntl (fs/fcntl.c:473) 
[ 26.042019][ T242] ? __pfx_do_fcntl (fs/fcntl.c:443) 
[ 26.042181][ T242] ? __fget_files (fs/file.c:1009) 
[ 26.042354][ T242] __x64_sys_connect (net/socket.c:2095) 
[ 26.042515][ T242] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 26.042681][ T242] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   26.042882][  T242] RIP: 0033:0x7f28d9a7a40b
[ 26.043046][ T242] 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
[   26.043610][  T242] RSP: 002b:00007f28d9125d30 EFLAGS: 00000293 ORIG_RAX: 000000000000002a
[   26.043850][  T242] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00007f28d9a7a40b
[   26.044085][  T242] RDX: 0000000000000010 RSI: 00007f28d9125d90 RDI: 0000000000000009
[   26.044325][  T242] RBP: 0000000000000009 R08: 0000000000000000 R09: 0000000000419480
[   26.044573][  T242] R10: 00007f28d9932598 R11: 0000000000000293 R12: 0000000000412df0
[   26.044809][  T242] R13: 0000000000000005 R14: 00007f28d9125d90 R15: 0000000000000000
| [   26.050079][  T242] 1 lock held by unsigned-md5_ip/242:
| [ 26.050242][ T242] #0: ffff888005a8aa58 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_stream_connect (net/ipv4/af_inet.c:748) 
| [   26.050552][  T242]
| [   26.050552][  T242] stack backtrace:
[   26.051023][  T242] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   26.051382][  T242] Call Trace:
[   26.051507][  T242]  <TASK>
[ 26.051597][ T242] dump_stack_lvl (lib/dump_stack.c:123) 
[ 26.051763][ T242] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 26.051930][ T242] tcp_ao_finish_connect (net/ipv4/tcp_ao.c:1183 (discriminator 7)) 
[ 26.052092][ T242] tcp_finish_connect (net/ipv4/tcp_input.c:6340) 
[ 26.052256][ T242] tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6576) 
[ 26.052452][ T242] ? 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) 
[ 26.052621][ T242] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.052747][ T242] ? __pfx_tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6455) 
[ 26.052946][ T242] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 26.053147][ T242] ? kvm_clock_get_cycles (./arch/x86/include/asm/preempt.h:94 arch/x86/kernel/kvmclock.c:80 arch/x86/kernel/kvmclock.c:86) 
[ 26.053309][ T242] ? 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)) 
[ 26.053429][ T242] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 26.053592][ T242] tcp_rcv_state_process (net/ipv4/tcp_input.c:6796) 
[ 26.053755][ T242] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 26.053912][ T242] ? __release_sock (./include/net/sock.h:1121 net/core/sock.c:3077) 
[ 26.054075][ T242] ? __pfx_tcp_rcv_state_process (net/ipv4/tcp_input.c:6751) 
[ 26.054272][ T242] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.054404][ T242] tcp_v4_do_rcv (net/ipv4/tcp_ipv4.c:1945) 
[ 26.054568][ T242] __release_sock (./include/net/sock.h:1121 net/core/sock.c:3077) 
[ 26.054739][ T242] release_sock (net/core/sock.c:3633) 
[ 26.054900][ T242] inet_stream_connect (net/ipv4/af_inet.c:751) 
[ 26.055063][ T242] __sys_connect (net/socket.c:2071 net/socket.c:2088) 
[ 26.055225][ T242] ? __pfx___sys_connect (net/socket.c:2078) 
[ 26.055387][ T242] ? do_fcntl (fs/fcntl.c:473) 
[ 26.055512][ T242] ? __pfx_do_fcntl (fs/fcntl.c:443) 
[ 26.055674][ T242] ? __fget_files (fs/file.c:1009) 
[ 26.055850][ T242] __x64_sys_connect (net/socket.c:2095) 
[ 26.056011][ T242] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 26.056174][ T242] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   26.056370][  T242] RIP: 0033:0x7f28d9a7a40b
[ 26.056538][ T242] 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
[   26.057104][  T242] RSP: 002b:00007f28d9125d30 EFLAGS: 00000293 ORIG_RAX: 000000000000002a
[   26.057348][  T242] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00007f28d9a7a40b
[   26.057589][  T242] RDX: 0000000000000010 RSI: 00007f28d9125d90 RDI: 0000000000000009
[   26.057826][  T242] RBP: 0000000000000009 R08: 0000000000000000 R09: 0000000000419480
[   26.058068][  T242] R10: 00007f28d9932598 R11: 0000000000000293 R12: 0000000000412df0


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