======================================
| [ 1886.137927][T12849] rcu_scheduler_active = 2, debug_locks = 1
| [ 1886.138152][T12849] no locks held by smcrouted/12849.
| [ 1886.138305][T12849]
| [ 1886.138305][T12849] stack backtrace:
[ 1886.138757][T12849] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 1886.139085][T12849] Call Trace:
[ 1886.139203][T12849]  <TASK>
[1886.139285][T12849] dump_stack_lvl (lib/dump_stack.c:123) 
[1886.139449][T12849] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[1886.139606][T12849] ip6mr_get_table (net/ipv6/ip6mr.c:132 (discriminator 11)) 
[1886.139762][T12849] ip6_mroute_setsockopt (net/ipv6/ip6mr.c:1670) 
[1886.139917][T12849] ? __pfx_ip6_mroute_setsockopt (net/ipv6/ip6mr.c:1658) 
[1886.140121][T12849] ? __lock_release (kernel/locking/lockdep.c:5501) 
[1886.140273][T12849] ? __might_fault (mm/memory.c:6716 mm/memory.c:6709) 
[1886.140435][T12849] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[1886.140590][T12849] ? __might_fault (mm/memory.c:6716 mm/memory.c:6709) 
[1886.140756][T12849] ? lock_acquire (kernel/locking/lockdep.c:5798) 
[1886.140904][T12849] ? __might_fault (mm/memory.c:6716 mm/memory.c:6709) 
[1886.141057][T12849] ? __might_fault (mm/memory.c:6716 mm/memory.c:6709) 
[1886.141214][T12849] do_ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:415) 
[1886.141374][T12849] ? __lock_release (kernel/locking/lockdep.c:5486) 
[1886.141538][T12849] ? __pfx_do_ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:395) 
[1886.141690][T12849] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5790) 
[1886.141847][T12849] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[1886.142001][T12849] ? validate_chain (kernel/locking/lockdep.c:3797 kernel/locking/lockdep.c:3817 kernel/locking/lockdep.c:3872) 
[1886.142157][T12849] ? is_bpf_text_address (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 kernel/bpf/core.c:769) 
[1886.142314][T12849] ? __pfx_validate_chain (kernel/locking/lockdep.c:3860) 
[1886.142469][T12849] ? 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) 
[1886.142623][T12849] ? mark_lock (kernel/locking/lockdep.c:4703 (discriminator 3)) 
[1886.142743][T12849] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[1886.142926][T12849] ? find_held_lock (kernel/locking/lockdep.c:5315) 
[1886.143085][T12849] ? ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:996) 
[1886.143233][T12849] ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:996) 
[1886.143385][T12849] rawv6_setsockopt (net/ipv6/raw.c:1054) 
[1886.143539][T12849] ? __pfx_rawv6_setsockopt (net/ipv6/raw.c:1039) 
[1886.143686][T12849] ? __lock_acquire (kernel/locking/lockdep.c:5202) 
[1886.143845][T12849] ? kfree (mm/slub.c:4716) 
[1886.143975][T12849] do_sock_setsockopt (net/socket.c:2336) 
[1886.144141][T12849] ? __pfx_do_sock_setsockopt (net/socket.c:2305) 
[1886.144311][T12849] ? __lock_release (kernel/locking/lockdep.c:5501) 
[1886.144478][T12849] ? fd_install (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:962 fs/file.c:612) 
[1886.144648][T12849] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[1886.144812][T12849] ? fdget (./include/linux/atomic/atomic-arch-fallback.h:479 ./include/linux/atomic/atomic-instrumented.h:50 fs/file.c:1114 fs/file.c:1128) 
[1886.144941][T12849] __sys_setsockopt (./include/linux/file.h:35 net/socket.c:2361) 
[1886.145105][T12849] ? __pfx___sys_setsockopt (net/socket.c:2349) 
[1886.145270][T12849] ? __sys_socket (net/socket.c:496 net/socket.c:1727) 
[1886.145443][T12849] ? __pfx___sys_socket (net/socket.c:1714) 
[1886.145612][T12849] __x64_sys_setsockopt (net/socket.c:2365) 
[1886.145774][T12849] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[1886.145973][T12849] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[1886.146143][T12849] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[ 1886.146342][T12849] RIP: 0033:0x7f4fe42d991e
[ 1886.146513][T12849] 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
[ 1886.147090][T12849] RSP: 002b:00007fff27130ae8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
[ 1886.147342][T12849] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4fe42d991e
[ 1886.147621][T12849] RDX: 00000000000000c8 RSI: 0000000000000029 RDI: 0000000000000008
[ 1886.147879][T12849] RBP: 0000000000000008 R08: 0000000000000004 R09: 0000000000000000
[ 1886.148120][T12849] R10: 00007fff27130b0c R11: 0000000000000246 R12: 0000000000000000


Finger prints:
lockdep_rcu_suspicious:ip6mr_get_table:ip6_mroute_setsockopt:do_ipv6_setsockopt:ipv6_setsockopt