======================================
| [   25.843988][  T233] 1 lock held by icmps-discard_i/233:
| [ 25.844155][ T233] #0: ffff888005313798 (sk_lock-AF_INET){+.+.}-{0:0}, at: do_tcp_setsockopt (net/ipv4/tcp.c:3809) 
| [   25.844632][  T233]
| [   25.844632][  T233] stack backtrace:
[   25.845125][  T233] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   25.845494][  T233] Call Trace:
[   25.845621][  T233]  <TASK>
[ 25.845706][ T233] dump_stack_lvl (lib/dump_stack.c:123) 
[ 25.845877][ T233] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 25.846044][ T233] __tcp_ao_do_lookup.part.0 (net/ipv4/tcp_ao.c:208) 
[ 25.846208][ T233] tcp_ao_add_cmd (net/ipv4/tcp_ao.c:1698) 
[ 25.846375][ T233] ? __pfx_tcp_ao_add_cmd (net/ipv4/tcp_ao.c:1597) 
[ 25.846542][ T233] ? 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) 
[ 25.846707][ T233] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 25.846896][ T233] ? mark_held_locks (kernel/locking/lockdep.c:4321) 
[ 25.847064][ T233] ? do_tcp_setsockopt (net/ipv4/tcp.c:3943) 
[ 25.847227][ T233] do_tcp_setsockopt (net/ipv4/tcp.c:3943) 
[ 25.847396][ T233] ? __pfx_do_tcp_setsockopt (net/ipv4/tcp.c:3705) 
[ 25.847555][ T233] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 25.847727][ T233] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 25.847892][ T233] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 25.848054][ T233] ? __fget_files (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 fs/file.c:1006) 
[ 25.848218][ T233] ? __pfx___lock_release (kernel/locking/lockdep.c:5477) 
[ 25.848377][ T233] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5790) 
[ 25.848537][ T233] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 25.848707][ T233] do_sock_setsockopt (net/socket.c:2334) 
[ 25.848869][ T233] ? __pfx_do_sock_setsockopt (net/socket.c:2303) 
[ 25.849039][ T233] ? fdget (fs/file.c:1121 fs/file.c:1128) 
[ 25.849165][ T233] __sys_setsockopt (./include/linux/file.h:35 net/socket.c:2359) 
[ 25.849327][ T233] ? __pfx___sys_setsockopt (net/socket.c:2347) 
[ 25.849490][ T233] ? __rseq_handle_notify_resume (kernel/rseq.c:316) 
[ 25.849687][ T233] ? do_user_addr_fault (./include/linux/mmap_lock.h:172 arch/x86/mm/fault.c:1417) 
[ 25.849851][ T233] ? __pfx___rseq_handle_notify_resume (kernel/rseq.c:316) 
[ 25.850058][ T233] __x64_sys_setsockopt (net/socket.c:2363) 
[ 25.850223][ T233] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 25.850422][ T233] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 25.850585][ T233] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   25.850783][  T233] RIP: 0033:0x7fdd7491991e
[ 25.850948][ T233] Code: 0f 1f 40 00 48 8b 15 e1 94 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b1 0f 1f 00 f3 0f 1e fa 49 89 ca b8 36 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 a9
All code
========
   0:	0f 1f 40 00          	nopl   0x0(%rax)
   4:	48 8b 15 e1 94 0a 00 	mov    0xa94e1(%rip),%rdx        # 0xa94ec
   b:	f7 d8                	neg    %eax
   d:	64 89 02             	mov    %eax,%fs:(%rdx)
  10:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
  17:	eb b1                	jmp    0xffffffffffffffca
  19:	0f 1f 00             	nopl   (%rax)
  1c:	f3 0f 1e fa          	endbr64
  20:	49 89 ca             	mov    %rcx,%r10
  23:	b8 36 00 00 00       	mov    $0x36,%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:	a9                   	.byte 0xa9

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:	a9                   	.byte 0xa9
[   25.851505][  T233] RSP: 002b:00007ffccd027c48 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
[   25.851750][  T233] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fdd7491991e
[   25.851990][  T233] RDX: 0000000000000026 RSI: 0000000000000006 RDI: 0000000000000009
[   25.852231][  T233] RBP: 0000000000000009 R08: 0000000000000120 R09: 0029383231736561
[   25.852468][  T233] R10: 00007ffccd027c50 R11: 0000000000000246 R12: 00007ffccd027d70
[   25.852709][  T233] R13: 0000000000000020 R14: 0000000000400000 R15: 0000000401fe000a
| [   26.076721][  T241] 1 lock held by icmps-discard_i/241:
| [ 26.076869][ T241] #0: ffff888005312a58 (sk_lock-AF_INET){+.+.}-{0:0}, at: do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
| [   26.077146][  T241]
| [   26.077146][  T241] stack backtrace:
[   26.077599][  T241] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   26.077926][  T241] Call Trace:
[   26.078041][  T241]  <TASK>
[ 26.078121][ T241] dump_stack_lvl (lib/dump_stack.c:123) 
[ 26.078281][ T241] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 26.078438][ T241] tcp_ao_copy_mkts_to_user (net/ipv4/tcp_ao.c:2232 (discriminator 7)) 
[ 26.078590][ T241] ? mark_held_locks (kernel/locking/lockdep.c:4321) 
[ 26.078748][ T241] ? __pfx_tcp_ao_copy_mkts_to_user (net/ipv4/tcp_ao.c:2106) 
[ 26.078928][ T241] ? stack_depot_save_flags (lib/stackdepot.c:664) 
[ 26.079087][ T241] ? kasan_save_stack (mm/kasan/common.c:48) 
[ 26.079236][ T241] ? kasan_save_track (./arch/x86/include/asm/current.h:49 mm/kasan/common.c:60 mm/kasan/common.c:69) 
[ 26.079380][ T241] ? kasan_save_free_info (mm/kasan/generic.c:582) 
[ 26.079525][ T241] ? __kasan_slab_free (mm/kasan/common.c:271) 
[ 26.079672][ T241] ? kfree (mm/slub.c:4579 mm/slub.c:4727) 
[ 26.079789][ T241] ? tcp_ao_parse_crypto (./include/net/tcp_ao.h:67 net/ipv4/tcp_ao.c:1436) 
[ 26.079966][ T241] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 26.080125][ T241] ? lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5827) 
[ 26.080274][ T241] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 26.080427][ T241] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 26.080572][ T241] ? do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 26.080720][ 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) 
[ 26.080868][ T241] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.080993][ T241] ? do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 26.081139][ T241] do_tcp_getsockopt (net/ipv4/tcp.c:4631) 
[ 26.081457][ T241] ? __pfx_do_tcp_getsockopt (net/ipv4/tcp.c:4300) 
[ 26.081607][ T241] ? tcp_ao_add_cmd (net/ipv4/tcp_ao.c:1737) 
[ 26.081773][ T241] ? release_sock (net/core/sock.c:3630) 
[ 26.081921][ T241] ? reacquire_held_locks (kernel/locking/lockdep.c:5350) 
[ 26.082066][ T241] ? release_sock (net/core/sock.c:3630) 
[ 26.082217][ T241] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 26.082363][ T241] ? validate_chain (kernel/locking/lockdep.c:3797 kernel/locking/lockdep.c:3817 kernel/locking/lockdep.c:3872) 
[ 26.082511][ T241] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 26.082663][ T241] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 26.082809][ T241] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860) 
[ 26.082965][ 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) 
[ 26.083114][ T241] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.083233][ T241] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 26.083392][ T241] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 26.083541][ T241] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 26.083687][ T241] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 26.083835][ T241] ? __pfx___lock_release (kernel/locking/lockdep.c:5477) 
[ 26.083980][ T241] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 26.084129][ T241] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[ 26.084279][ T241] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 26.084426][ T241] ? __might_fault (mm/memory.c:6705 mm/memory.c:6698) 
[ 26.084574][ T241] tcp_getsockopt (net/ipv4/tcp.c:4673 net/ipv4/tcp.c:4664) 
[ 26.084724][ T241] do_sock_getsockopt (net/socket.c:2396) 
[ 26.084873][ T241] ? __fget_files (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 fs/file.c:1006) 
[ 26.085023][ T241] ? __pfx_do_sock_getsockopt (net/socket.c:2374) 
[ 26.085179][ T241] ? fdget (fs/file.c:1121 fs/file.c:1128) 
[ 26.085301][ T241] __sys_getsockopt (./include/linux/file.h:35 net/socket.c:2428) 
[ 26.085454][ T241] ? __sys_setsockopt (net/socket.c:2360) 
[ 26.085605][ T241] ? __pfx___sys_getsockopt (net/socket.c:2415) 
[ 26.085757][ T241] ? do_user_addr_fault (./include/linux/rcupdate.h:882 ./include/linux/mm.h:729 arch/x86/mm/fault.c:1340) 
[ 26.085910][ T241] __x64_sys_getsockopt (net/socket.c:2432) 
[ 26.086055][ T241] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 26.086242][ T241] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 26.086393][ T241] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   26.086579][  T241] RIP: 0033:0x7fdd7491946e
[ 26.086738][ T241] 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
[   26.087256][  T241] RSP: 002b:00007fdd73fc49c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
[   26.087482][  T241] RAX: ffffffffffffffda RBX: 00007fdd73fc4c80 RCX: 00007fdd7491946e
[   26.087709][  T241] RDX: 0000000000000029 RSI: 0000000000000006 RDI: 000000000000000a
[   26.087928][  T241] RBP: 00007fdd73fc49e0 R08: 00007fdd73fc49dc R09: 0000000000000064
[   26.088153][  T241] R10: 00007fdd73fc49e0 R11: 0000000000000246 R12: 000000000000000a
[   26.088374][  T241] R13: 0000000000000064 R14: 0000000000000020 R15: 0000000000000064
| [   26.095745][  T241] 1 lock held by icmps-discard_i/241:
| [ 26.095901][ T241] #0: ffff888005312a58 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_stream_connect (net/ipv4/af_inet.c:748) 
| [   26.096186][  T241]
| [   26.096186][  T241] stack backtrace:
[   26.096680][  T241] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   26.097016][  T241] Call Trace:
[   26.097134][  T241]  <TASK>
[ 26.097218][ T241] dump_stack_lvl (lib/dump_stack.c:123) 
[ 26.097380][ T241] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 26.097541][ T241] tcp_ao_finish_connect (net/ipv4/tcp_ao.c:1183 (discriminator 7)) 
[ 26.097700][ T241] tcp_finish_connect (net/ipv4/tcp_input.c:6340) 
[ 26.097858][ T241] tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6576) 
[ 26.098050][ 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) 
[ 26.098209][ T241] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.098329][ T241] ? __pfx_tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6455) 
[ 26.098519][ T241] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 26.098708][ T241] ? kvm_clock_get_cycles (./arch/x86/include/asm/preempt.h:94 arch/x86/kernel/kvmclock.c:80 arch/x86/kernel/kvmclock.c:86) 
[ 26.098867][ 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)) 
[ 26.098987][ T241] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[ 26.099142][ T241] tcp_rcv_state_process (net/ipv4/tcp_input.c:6796) 
[ 26.099295][ T241] ? __lock_release (kernel/locking/lockdep.c:5501) 
[ 26.099445][ T241] ? __release_sock (./include/net/sock.h:1121 net/core/sock.c:3077) 
[ 26.099603][ T241] ? __pfx_tcp_rcv_state_process (net/ipv4/tcp_input.c:6751) 
[ 26.099790][ T241] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[ 26.099913][ T241] tcp_v4_do_rcv (net/ipv4/tcp_ipv4.c:1945) 
[ 26.100074][ T241] __release_sock (./include/net/sock.h:1121 net/core/sock.c:3077) 
[ 26.100237][ T241] release_sock (net/core/sock.c:3633) 
[ 26.100389][ T241] inet_stream_connect (net/ipv4/af_inet.c:751) 
[ 26.100557][ T241] __sys_connect (net/socket.c:2071 net/socket.c:2088) 
[ 26.100711][ T241] ? __pfx___sys_connect (net/socket.c:2078) 
[ 26.100863][ T241] ? do_fcntl (fs/fcntl.c:473) 
[ 26.100980][ T241] ? __pfx_do_fcntl (fs/fcntl.c:443) 
[ 26.101138][ T241] ? __fget_files (fs/file.c:1009) 
[ 26.101301][ T241] __x64_sys_connect (net/socket.c:2095) 
[ 26.101454][ T241] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 26.101613][ T241] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   26.101799][  T241] RIP: 0033:0x7fdd7491940b
[ 26.101958][ 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
[   26.102491][  T241] RSP: 002b:00007fdd73fc4d80 EFLAGS: 00000293 ORIG_RAX: 000000000000002a
[   26.102723][  T241] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00007fdd7491940b
[   26.102952][  T241] RDX: 0000000000000010 RSI: 00007fdd73fc4e00 RDI: 000000000000000a
[   26.103180][  T241] RBP: 000000000000000a R08: 0000000000000000 R09: 0000000000414400
[   26.103406][  T241] R10: 00007fdd747d1598 R11: 0000000000000293 R12: 000000000040e198


Finger prints:
lockdep_rcu_suspicious:tcp_ao_add_cmd:do_tcp_setsockopt:do_sock_setsockopt:__sys_setsockopt
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