======================================
| [   20.634308][    C0] rcu_scheduler_active = 2, debug_locks = 1
| [   20.634704][    C0] no locks held by udpgso_bench_tx/317.
| [   20.634973][    C0]
| [   20.634973][    C0] stack backtrace:
[   20.635318][    C0] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   20.635320][    C0] Call Trace:
[   20.635322][    C0]  <IRQ>
[ 20.635324][ C0] dump_stack_lvl (lib/dump_stack.c:123) 
[ 20.635336][ C0] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6866) 
[ 20.635349][ C0] veth_xdp_rcv (drivers/net/veth.c:907 (discriminator 9)) 
[ 20.635359][ C0] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 20.635368][ C0] ? debug_object_activate (lib/debugobjects.c:837) 
[ 20.635378][ C0] ? __pfx_debug_object_activate (lib/debugobjects.c:805) 
[ 20.635383][ C0] ? __pfx_veth_xdp_rcv (drivers/net/veth.c:899) 
[ 20.635390][ C0] ? mark_held_locks (kernel/locking/lockdep.c:4326) 
[ 20.635396][ C0] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 20.635400][ C0] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4473) 
[ 20.635404][ C0] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 20.635409][ C0] ? __mod_timer (kernel/time/timer.c:1061) 
[ 20.635422][ C0] veth_poll (drivers/net/veth.c:977) 
[ 20.635426][ C0] ? __pfx_veth_poll (drivers/net/veth.c:965) 
[ 20.635438][ C0] ? addrconf_rs_timer (./arch/x86/include/asm/atomic.h:93 ./include/linux/atomic/atomic-arch-fallback.h:949 ./include/linux/atomic/atomic-instrumented.h:401 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/addrconf.h:416 net/ipv6/addrconf.c:4063) 
[ 20.635448][ C0] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 20.635453][ C0] ? validate_chain (kernel/locking/lockdep.c:3802 kernel/locking/lockdep.c:3822 kernel/locking/lockdep.c:3877) 
[ 20.635464][ C0] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 20.635467][ C0] ? validate_chain (kernel/locking/lockdep.c:3802 kernel/locking/lockdep.c:3822 kernel/locking/lockdep.c:3877) 
[ 20.635474][ C0] __napi_poll.constprop.0 (net/core/dev.c:7413) 
[ 20.635480][ C0] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 20.635486][ C0] net_rx_action (net/core/dev.c:7477 net/core/dev.c:7599) 
[ 20.635498][ C0] ? __pfx_net_rx_action (net/core/dev.c:7561) 
[ 20.635501][ C0] ? sched_balance_domains (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:871 kernel/sched/fair.c:12258) 
[ 20.635519][ C0] ? __pfx_sched_balance_domains (kernel/sched/fair.c:12189) 
[ 20.635522][ C0] ? __lock_release (kernel/locking/lockdep.c:5534) 
[ 20.635533][ C0] handle_softirqs (kernel/softirq.c:579) 
[ 20.635548][ C0] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 20.635551][ C0] irq_exit_rcu (kernel/softirq.c:698) 
[ 20.635555][ C0] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1049 arch/x86/kernel/apic/apic.c:1049) 
[   20.635562][    C0]  </IRQ>
[   20.635562][    C0]  <TASK>
[ 20.635565][ C0] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 20.635569][ C0] RIP: 0010:do_user_addr_fault (arch/x86/mm/fault.c:1293) 
[ 20.635576][ C0] Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b6 0a 00 00 41 f6 87 91 00 00 00 02 0f 84 82 04 00 00 e8 ef 3f 42 00 fb 0f 1f 44 00 00 <48> 89 e8 48 89 e9 4c 89 f2 83 e0 40 0f 95 c3 48 89 44 24 08 48 89
All code
========
   0:	48 89 fa             	mov    %rdi,%rdx
   3:	48 c1 ea 03          	shr    $0x3,%rdx
   7:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   b:	0f 85 b6 0a 00 00    	jne    0xac7
  11:	41 f6 87 91 00 00 00 	testb  $0x2,0x91(%r15)
  18:	02 
  19:	0f 84 82 04 00 00    	je     0x4a1
  1f:	e8 ef 3f 42 00       	call   0x424013
  24:	fb                   	sti
  25:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  2a:*	48 89 e8             	mov    %rbp,%rax		<-- trapping instruction
  2d:	48 89 e9             	mov    %rbp,%rcx
  30:	4c 89 f2             	mov    %r14,%rdx
  33:	83 e0 40             	and    $0x40,%eax
  36:	0f 95 c3             	setne  %bl
  39:	48 89 44 24 08       	mov    %rax,0x8(%rsp)
  3e:	48                   	rex.W
  3f:	89                   	.byte 0x89

Code starting with the faulting instruction
===========================================
   0:	48 89 e8             	mov    %rbp,%rax
   3:	48 89 e9             	mov    %rbp,%rcx
   6:	4c 89 f2             	mov    %r14,%rdx
   9:	83 e0 40             	and    $0x40,%eax
   c:	0f 95 c3             	setne  %bl
   f:	48 89 44 24 08       	mov    %rax,0x8(%rsp)
  14:	48                   	rex.W
  15:	89                   	.byte 0x89
[   20.635578][    C0] RSP: 0000:ffffc900006a7eb8 EFLAGS: 00000202
[   20.635582][    C0] RAX: 0000000000004b6b RBX: ffff888009984640 RCX: ffffffff94a48d5f
[   20.635584][    C0] RDX: 0000000000000000 RSI: ffffffff97f0b5e2 RDI: ffffffff976539c0
[   20.635586][    C0] RBP: 0000000000000006 R08: 0000000000000001 R09: 0000000000000001
[   20.635587][    C0] R10: ffffffff9946f097 R11: 0000000000000000 R12: 000000000044a000
[   20.635589][    C0] R13: ffff88800c665040 R14: ffffc900006a7fe0 R15: ffffc900006a7f58
[ 20.635597][ C0] ? trace_irq_enable.constprop.0 (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 ./include/linux/cpumask.h:587 ./include/linux/cpumask.h:1143 ./include/trace/events/preemptirq.h:40) 
[ 20.635607][ C0] ? do_user_addr_fault (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 arch/x86/mm/fault.c:1282) 
[ 20.635613][ C0] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:736) 
[ 20.635619][ C0] exc_page_fault (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:109 ./arch/x86/include/asm/irqflags.h:151 arch/x86/mm/fault.c:1488 arch/x86/mm/fault.c:1538) 
[ 20.635625][ C0] asm_exc_page_fault (./arch/x86/include/asm/idtentry.h:623) 
[   20.635628][    C0] RIP: 0033:0x7fd8616d4a4c
[ 20.635632][ C0] Code: 00 00 00 74 a0 83 f9 c0 0f 87 56 fe ff ff 62 e1 fe 28 6f 4e 01 48 29 fe 48 83 c7 3f 49 8d 0c 10 48 83 e7 c0 48 01 fe 48 29 f9 <f3> a4 62 c1 fe 28 7f 00 62 c1 fe 28 7f 48 01 c3 0f 1f 40 00 4c 8b
All code
========
   0:	00 00                	add    %al,(%rax)
   2:	00 74 a0 83          	add    %dh,-0x7d(%rax,%riz,4)
   6:	f9                   	stc
   7:	c0 0f 87             	rorb   $0x87,(%rdi)
   a:	56                   	push   %rsi
   b:	fe                   	(bad)
   c:	ff                   	(bad)
   d:	ff 62 e1             	jmp    *-0x1f(%rdx)
  10:	fe                   	(bad)
  11:	28 6f 4e             	sub    %ch,0x4e(%rdi)
  14:	01 48 29             	add    %ecx,0x29(%rax)
  17:	fe 48 83             	decb   -0x7d(%rax)
  1a:	c7                   	(bad)
  1b:	3f                   	(bad)
  1c:	49 8d 0c 10          	lea    (%r8,%rdx,1),%rcx
  20:	48 83 e7 c0          	and    $0xffffffffffffffc0,%rdi
  24:	48 01 fe             	add    %rdi,%rsi
  27:	48 29 f9             	sub    %rdi,%rcx
  2a:*	f3 a4                	rep movsb %ds:(%rsi),%es:(%rdi)		<-- trapping instruction
  2c:	62 c1 fe 28 7f 00    	vmovdqu64 %ymm16,(%r8)
  32:	62 c1 fe 28 7f 48 01 	vmovdqu64 %ymm17,0x20(%r8)
  39:	c3                   	ret
  3a:	0f 1f 40 00          	nopl   0x0(%rax)
  3e:	4c                   	rex.WR
  3f:	8b                   	.byte 0x8b

Code starting with the faulting instruction
===========================================
   0:	f3 a4                	rep movsb %ds:(%rsi),%es:(%rdi)
   2:	62 c1 fe 28 7f 00    	vmovdqu64 %ymm16,(%r8)
   8:	62 c1 fe 28 7f 48 01 	vmovdqu64 %ymm17,0x20(%r8)
   f:	c3                   	ret
  10:	0f 1f 40 00          	nopl   0x0(%rax)
  14:	4c                   	rex.WR
  15:	8b                   	.byte 0x8b
[   20.635634][    C0] RSP: 002b:00007ffd6c2ccc68 EFLAGS: 00010202
[   20.635637][    C0] RAX: 000000000044513c RBX: 0000000000000001 RCX: 000000000000b13b
[   20.635638][    C0] RDX: 000000000000ffff RSI: 000000000040a004 RDI: 000000000044a000
[   20.635640][    C0] RBP: 00007ffd6c2ccdb0 R08: 000000000044513c R09: 00007ffd6c2ccc24
[   20.635642][    C0] R10: 00007fd86161beb8 R11: 00007fd8616d4700 R12: 000000000000000a


Finger prints:
lockdep_rcu_suspicious:veth_xdp_rcv:veth_poll:net_rx_action:handle_softirqs