======================================
| [   68.930775][  T648] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).
| [   69.536728][    C0] ------------[ cut here ]------------
| [   69.537287][    C0] WARNING: CPU: 0 PID: 687 at ./include/net/sch_generic.h:843 __dev_xmit_skb (./include/net/sch_generic.h:843 ./include/net/sch_generic.h:889 ./include/net/sch_generic.h:895 net/core/dev.c:4168)
| [   69.537960][    C0] Modules linked in: netdevsim [last unloaded: netdevsim]
[   69.539154][    C0] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   69.539633][    C0] RIP: 0010:__dev_xmit_skb (./include/net/sch_generic.h:843 ./include/net/sch_generic.h:889 ./include/net/sch_generic.h:895 net/core/dev.c:4168)
[   69.540014][    C0] Code: ea 03 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 09 84 c0 74 05 e8 bb 04 ef fe 41 c6 87 b0 01 00 00 00 45 31 ed e9 f5 f5 ff ff 90 <0f> 0b 90 e9 00 ff ff ff be 08 00 00 00 48 89 ef e8 f5 0a ef fe f0
All code
========
   0:	ea                   	(bad)
   1:	03 0f                	add    (%rdi),%ecx
   3:	b6 04                	mov    $0x4,%dh
   5:	02 48 89             	add    -0x77(%rax),%cl
   8:	fa                   	cli
   9:	83 e2 07             	and    $0x7,%edx
   c:	38 d0                	cmp    %dl,%al
   e:	7f 09                	jg     0x19
  10:	84 c0                	test   %al,%al
  12:	74 05                	je     0x19
  14:	e8 bb 04 ef fe       	call   0xfffffffffeef04d4
  19:	41 c6 87 b0 01 00 00 	movb   $0x0,0x1b0(%r15)
  20:	00 
  21:	45 31 ed             	xor    %r13d,%r13d
  24:	e9 f5 f5 ff ff       	jmp    0xfffffffffffff61e
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	e9 00 ff ff ff       	jmp    0xffffffffffffff32
  32:	be 08 00 00 00       	mov    $0x8,%esi
  37:	48 89 ef             	mov    %rbp,%rdi
  3a:	e8 f5 0a ef fe       	call   0xfffffffffeef0b34
  3f:	f0                   	lock

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	e9 00 ff ff ff       	jmp    0xffffffffffffff08
   8:	be 08 00 00 00       	mov    $0x8,%esi
   d:	48 89 ef             	mov    %rbp,%rdi
  10:	e8 f5 0a ef fe       	call   0xfffffffffeef0b0a
  15:	f0                   	lock
[   69.541324][    C0] RSP: 0018:ffffc900000076b8 EFLAGS: 00010202
[   69.541809][    C0] RAX: 0000000000000001 RBX: ffffe8ffffc04b70 RCX: 0000000000000000
[   69.542361][    C0] RDX: 0000000000000007 RSI: ffffffff8b05d540 RDI: ffff8880096d7606
[   69.542923][    C0] RBP: ffff888005175198 R08: 0000000000000001 R09: 0000000000000001
[   69.543472][    C0] R10: 000000000000a000 R11: ffff888005175228 R12: ffff888008e04118
[   69.544047][    C0] R13: ffff8880096d7600 R14: ffff888005175210 R15: ffff888005175000
[   69.544770][    C0] FS:  00007f2ff3289b80(0000) GS:ffff8880a93fc000(0000) knlGS:0000000000000000
[   69.545421][    C0] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   69.545897][    C0] CR2: 00007f2ff33d46c0 CR3: 000000000a896002 CR4: 0000000000772ef0
[   69.546452][    C0] PKRU: 55555554
[   69.546738][    C0] Call Trace:
[   69.547015][    C0]  <IRQ>
[   69.547215][    C0]  ? napi_hash_add (net/core/dev.c:4073)
[   69.547596][    C0]  ? dev_get_stats (net/core/dev.c:4143)
[   69.547982][    C0]  __dev_queue_xmit (net/core/dev.c:4786)
[   69.548361][    C0]  ? netdev_core_pick_tx (net/core/dev.c:4728)
[   69.548738][    C0]  ? eth_header (net/ethernet/eth.c:100)
[   69.549113][    C0]  ? neigh_resolve_output (./include/linux/netdevice.h:3422 net/core/neighbour.c:1589 net/core/neighbour.c:1574)
[   69.549486][    C0]  ? __neigh_update (./include/linux/rcupdate.h:331 ./include/linux/rcupdate.h:867 net/core/neighbour.c:1476)
[   69.549866][    C0]  __neigh_update (./include/linux/instrumented.h:96 (discriminator 2) ./include/linux/atomic/atomic-instrumented.h:400 (discriminator 2) ./include/linux/refcount.h:389 (discriminator 2) ./include/linux/refcount.h:432 (discriminator 2) ./include/linux/refcount.h:450 (discriminator 2) ./include/net/neighbour.h:458 (discriminator 2) net/core/neighbour.c:1494 (discriminator 2))
[   69.550245][    C0]  arp_process.constprop.0 (./include/linux/instrumented.h:96 ./include/linux/atomic/atomic-instrumented.h:400 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/neighbour.h:458 net/ipv4/arp.c:937)
[   69.550632][    C0]  ? arp_send (net/ipv4/arp.c:701)
[   69.550910][    C0]  ? arch_stack_walk (arch/x86/kernel/stacktrace.c:26)
[   69.551303][    C0]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   69.551692][    C0]  ? arp_rcv.part.0 (net/ipv4/arp.c:968)
[   69.552056][    C0]  __netif_receive_skb_one_core (net/core/dev.c:6131)
[   69.552509][    C0]  ? __netif_receive_skb_list_core (net/core/dev.c:6131)
[   69.552976][    C0]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[   69.553347][    C0]  ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5831)
[   69.553733][    C0]  ? netif_receive_skb_internal (./include/linux/rcupdate.h:331 (discriminator 16) ./include/linux/rcupdate.h:867 (discriminator 16) net/core/dev.c:6324 (discriminator 16))
[   69.554204][    C0]  netif_receive_skb_internal (net/core/dev.c:6337)
[   69.554574][    C0]  ? __netif_receive_skb (net/core/dev.c:6316)
[   69.554945][    C0]  ? mark_held_locks (kernel/locking/lockdep.c:4325)
[   69.555308][    C0]  ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194)
[   69.555781][    C0]  ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4472)
[   69.556146][    C0]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[   69.556514][    C0]  netif_receive_skb (net/core/dev.c:6396)
[   69.556903][    C0] nsim_poll (drivers/net/netdevsim/netdev.c:439 drivers/net/netdevsim/netdev.c:454) netdevsim
[   69.557287][    C0]  ? nsim_start_peer_tx_queue.isra.0 (drivers/net/netdevsim/netdev.c:450) netdevsim
[   69.557845][    C0]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[   69.558211][    C0]  __napi_poll.constprop.0 (net/core/dev.c:7668)
[   69.558578][    C0]  net_rx_action (net/core/dev.c:7730 net/core/dev.c:7882)
[   69.558966][    C0]  ? run_backlog_napi (net/core/dev.c:7844)
[   69.559317][    C0]  ? clockevents_program_event (kernel/time/clockevents.c:326)
[   69.559677][    C0]  ? lock_downgrade (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 ./arch/x86/include/asm/irqflags.h:159 kernel/locking/lockdep.c:5765)
[   69.560034][    C0]  ? kvm_clock_get_cycles (./arch/x86/include/asm/preempt.h:95 arch/x86/kernel/kvmclock.c:80 arch/x86/kernel/kvmclock.c:86)
[   69.560397][    C0]  ? ktime_get (kernel/time/timekeeping.c:387 (discriminator 4) kernel/time/timekeeping.c:404 (discriminator 4) kernel/time/timekeeping.c:826 (discriminator 4))
[   69.560686][    C0]  ? clockevents_program_event (kernel/time/clockevents.c:336 (discriminator 3))
[   69.561160][    C0]  handle_softirqs (kernel/softirq.c:623)
[   69.561522][    C0]  ? __neigh_event_send (./include/linux/bottom_half.h:33 net/core/neighbour.c:1273)
[   69.561882][    C0]  do_softirq (kernel/softirq.c:523 kernel/softirq.c:510)
[   69.562145][    C0]  </IRQ>
[   69.562329][    C0]  <TASK>
[   69.562511][    C0]  __local_bh_enable_ip (kernel/softirq.c:450)
[   69.562866][    C0]  __neigh_event_send (net/core/neighbour.c:1274)
[   69.563222][    C0]  neigh_resolve_output (net/core/neighbour.c:1578)
[   69.563571][    C0]  ? ___neigh_create (net/core/neighbour.c:727)
[   69.563944][    C0]  ip_finish_output2 (./include/net/neighbour.h:556 net/ipv4/ip_output.c:237)
[   69.564299][    C0]  ? ip_skb_dst_mtu (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 ./include/net/ip.h:504 ./include/net/ip.h:518)
[   69.564651][    C0]  ? ip_fragment.constprop.0 (net/ipv4/ip_output.c:201)
[   69.565000][    C0]  ? ip_skb_dst_mtu (./include/net/ip.h:523)
[   69.565362][    C0]  ? __ip_finish_output (./include/linux/skbuff.h:1724 ./include/linux/skbuff.h:5149 net/ipv4/ip_output.c:309)
[   69.566008][    C0]  ip_output (./include/linux/netfilter.h:414 net/ipv4/ip_output.c:438)
[   69.566291][    C0]  __ip_queue_xmit (./include/net/dst.h:464 net/ipv4/ip_output.c:131 net/ipv4/ip_output.c:534)
[   69.566660][    C0]  ? __skb_clone (./arch/x86/include/asm/atomic.h:53 (discriminator 4) ./include/linux/atomic/atomic-arch-fallback.h:992 (discriminator 4) ./include/linux/atomic/atomic-instrumented.h:436 (discriminator 4) net/core/skbuff.c:1585 (discriminator 4))
[   69.567027][    C0]  __tcp_transmit_skb (net/ipv4/tcp_output.c:1628)
[   69.567671][    C0]  ? __tcp_select_window (net/ipv4/tcp_output.c:1449)
[   69.568050][    C0]  tcp_connect (net/ipv4/tcp_output.c:1646 net/ipv4/tcp_output.c:4335)
[   69.568416][    C0]  tcp_v4_connect (net/ipv4/tcp_ipv4.c:347)
[   69.568792][    C0]  ? bpf_iter_init_tcp (net/ipv4/tcp_ipv4.c:225)
[   69.569411][    C0]  ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:107 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116)
[   69.569837][    C0]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   69.570192][    C0]  __inet_stream_connect (net/ipv4/af_inet.c:679)
[   69.570553][    C0]  ? __local_bh_enable_ip (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 kernel/softirq.c:455)
[   69.571167][    C0]  ? __inet_stream_connect (net/ipv4/af_inet.c:746)
[   69.571518][    C0]  inet_stream_connect (net/ipv4/af_inet.c:751)
[   69.571880][    C0]  __sys_connect (./include/linux/file.h:62 ./include/linux/file.h:83 net/socket.c:2111)
[   69.572232][    C0]  ? __sys_connect_file (net/socket.c:2109)
[   69.572846][    C0]  ? do_fcntl (fs/fcntl.c:471)
[   69.573117][    C0]  ? f_getown (fs/fcntl.c:446)
[   69.573387][    C0]  ? __rseq_handle_notify_resume (kernel/rseq.c:442)
[   69.573860][    C0]  ? rseq_get_rseq_cs.isra.0 (kernel/rseq.c:425)
[   69.574236][    C0]  __x64_sys_connect (net/socket.c:2124)
[   69.574871][    C0]  ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4472)
[   69.575230][    C0]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[   69.575592][    C0]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   69.576311][    C0] RIP: 0033:0x7f2ff33e5d67
[   69.576698][    C0] Code: 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 18 89 54 24 0c 48 89 34 24 89
All code
========
   0:	64 89 01             	mov    %eax,%fs:(%rcx)
   3:	48 83 c8 ff          	or     $0xffffffffffffffff,%rax
   7:	c3                   	ret
   8:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
   f:	00 00 00 
  12:	90                   	nop
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  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 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 18          	sub    $0x18,%rsp
  37:	89 54 24 0c          	mov    %edx,0xc(%rsp)
  3b:	48 89 34 24          	mov    %rsi,(%rsp)
  3f:	89                   	.byte 0x89

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 18          	sub    $0x18,%rsp
   d:	89 54 24 0c          	mov    %edx,0xc(%rsp)
  11:	48 89 34 24          	mov    %rsi,(%rsp)
  15:	89                   	.byte 0x89
[   69.578239][    C0] RSP: 002b:00007fff261fb898 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
[   69.578771][    C0] RAX: ffffffffffffffda RBX: 00005579e10c0cf0 RCX: 00007f2ff33e5d67
[   69.579291][    C0] RDX: 0000000000000010 RSI: 00007fff261fc210 RDI: 0000000000000007
[   69.580092][    C0] RBP: 00007fff261fc210 R08: 00007fff261fb8a0 R09: 0000000000000010
[   69.580618][    C0] R10: 00000000000004d2 R11: 0000000000000246 R12: 0000000000000010


Finger prints:
__dev_xmit_skb:__dev_queue_xmit:__neigh_update:__netif_receive_skb_one_core:netif_receive_skb_internal