======================================
| [ 38.167792][ T936] #0: ffffffffb8459670 (cb_lock){++++}-{3:3}, at: genl_rcv (net/netlink/genetlink.c:1219) 
| [ 38.168098][ T936] #1: ffffffffb8402408 (rtnl_mutex){+.+.}-{3:3}, at: netdev_nl_napi_set_doit (net/core/netdev-genl.c:350) 
| [   38.168429][  T936]
| [   38.168429][  T936] stack backtrace:
[   38.168949][  T936] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   38.169165][  T936] Call Trace:
[   38.169304][  T936]  <TASK>
[ 38.169400][ T936] dump_stack_lvl (lib/dump_stack.c:123) 
[ 38.169590][ T936] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) 
[ 38.169775][ T936] napi_by_id (net/core/dev.c:6300 (discriminator 7)) 
[ 38.169915][ T936] netdev_nl_napi_set_doit (net/core/netdev-genl.c:350) 
[ 38.170089][ T936] ? __pfx_netdev_nl_napi_set_doit (net/core/netdev-genl.c:338) 
[ 38.170312][ T936] ? __nla_parse (lib/nlattr.c:732) 
[ 38.170489][ T936] ? genl_family_rcv_msg_attrs_parse.constprop.0 (net/netlink/genetlink.c:947) 
[ 38.170761][ T936] genl_family_rcv_msg_doit (net/netlink/genetlink.c:1115) 
[ 38.170938][ T936] ? __pfx_genl_family_rcv_msg_doit (net/netlink/genetlink.c:1088) 
[ 38.171150][ T936] ? __pfx___lock_release (kernel/locking/lockdep.c:5477) 
[ 38.171326][ T936] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5790) 
[ 38.171513][ T936] ? validate_chain (kernel/locking/lockdep.c:3797 kernel/locking/lockdep.c:3817 kernel/locking/lockdep.c:3872) 
[ 38.171694][ T936] genl_family_rcv_msg (net/netlink/genetlink.c:1195) 
[ 38.171875][ T936] ? __pfx_genl_family_rcv_msg (net/netlink/genetlink.c:1160) 
[ 38.172055][ T936] ? __pfx_netdev_nl_napi_set_doit (net/core/netdev-genl.c:338) 
[ 38.172285][ T936] genl_rcv_msg (net/netlink/genetlink.c:65 net/netlink/genetlink.c:1211) 
[ 38.172463][ T936] netlink_rcv_skb (net/netlink/af_netlink.c:2536) 
[ 38.172641][ T936] ? __pfx_genl_rcv_msg (net/netlink/genetlink.c:1201) 
[ 38.172819][ T936] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2513) 
[ 38.173008][ T936] ? genl_rcv (net/netlink/genetlink.c:1219) 
[ 38.173141][ T936] ? __pfx_down_read (kernel/locking/rwsem.c:1522) 
[ 38.173317][ T936] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340) 
[ 38.173495][ T936] genl_rcv (net/netlink/genetlink.c:1220) 
[ 38.173628][ T936] netlink_unicast (net/netlink/af_netlink.c:1316 net/netlink/af_netlink.c:1342) 
[ 38.173811][ T936] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1327) 
[ 38.173987][ T936] ? __wake_up (kernel/sched/wait.c:110 kernel/sched/wait.c:127) 
[ 38.174128][ T936] netlink_sendmsg (net/netlink/af_netlink.c:1886) 
[ 38.174310][ T936] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1805) 
[ 38.174491][ T936] ? fdget (./include/linux/atomic/atomic-arch-fallback.h:479 ./include/linux/atomic/atomic-instrumented.h:50 fs/file.c:1114 fs/file.c:1128) 
[ 38.174636][ T936] __sys_sendto (net/socket.c:729 net/socket.c:744 net/socket.c:2216) 
[ 38.174816][ T936] ? __pfx___sys_sendto (net/socket.c:2186) 
[ 38.175003][ T936] ? do_user_addr_fault (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/linux/mm.h:729 arch/x86/mm/fault.c:1340) 
[ 38.175182][ T936] ? __pfx___lock_release (kernel/locking/lockdep.c:5477) 
[ 38.175352][ T936] ? __up_read (./arch/x86/include/asm/atomic64_64.h:79 ./include/linux/atomic/atomic-arch-fallback.h:2749 ./include/linux/atomic/atomic-long.h:184 ./include/linux/atomic/atomic-instrumented.h:3317 kernel/locking/rwsem.c:1345) 
[ 38.175530][ T936] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 52)) 
[ 38.175706][ T936] ? __pfx___up_read (kernel/locking/rwsem.c:1337) 
[ 38.175888][ T936] ? do_user_addr_fault (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/linux/mm.h:729 arch/x86/mm/fault.c:1340) 
[ 38.176068][ T936] ? do_user_addr_fault (./include/linux/rcupdate.h:882 ./include/linux/mm.h:729 arch/x86/mm/fault.c:1340) 
[ 38.176247][ T936] __x64_sys_sendto (net/socket.c:2224) 
[ 38.176420][ T936] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4347 kernel/locking/lockdep.c:4406) 
[ 38.176638][ T936] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 38.176813][ T936] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   38.177031][  T936] RIP: 0033:0x7fdc4fc7e700
[ 38.177213][ T936] Code: ff ff 64 89 02 eb bd 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 1d 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 68 c3 0f 1f 80 00 00 00 00 41 54 48 83 ec 20
All code
========
   0:	ff                   	(bad)
   1:	ff 64 89 02          	jmp    *0x2(%rcx,%rcx,4)
   5:	eb bd                	jmp    0xffffffffffffffc4
   7:	0f 1f 00             	nopl   (%rax)
   a:	f3 0f 1e fa          	endbr64
   e:	41 89 ca             	mov    %ecx,%r10d
  11:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  18:	00 
  19:	85 c0                	test   %eax,%eax
  1b:	75 1d                	jne    0x3a
  1d:	45 31 c9             	xor    %r9d,%r9d
  20:	45 31 c0             	xor    %r8d,%r8d
  23:	b8 2c 00 00 00       	mov    $0x2c,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 68                	ja     0x9a
  32:	c3                   	ret
  33:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  3a:	41 54                	push   %r12
  3c:	48 83 ec 20          	sub    $0x20,%rsp

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 68                	ja     0x70
   8:	c3                   	ret
   9:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  10:	41 54                	push   %r12
  12:	48 83 ec 20          	sub    $0x20,%rsp
[   38.177834][  T936] RSP: 002b:00007ffe782cf238 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   38.178102][  T936] RAX: ffffffffffffffda RBX: 00007ffe782cf250 RCX: 00007fdc4fc7e700
[   38.178374][  T936] RDX: 0000000000000034 RSI: 00007fdc4faeb270 RDI: 0000000000000005
[   38.178634][  T936] RBP: 00007fdc4faeb010 R08: 0000000000000000 R09: 0000000000000000
[   38.178893][  T936] R10: 0000000000000000 R11: 0000000000000246 R12: 000000001a5e82f0


Finger prints:
lockdep_rcu_suspicious:napi_by_id:netdev_nl_napi_set_doit:genl_family_rcv_msg_doit:genl_family_rcv_msg