rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=2b2/1/0x4000000000000002 softirq=40877/40878 fqs=5205 
	(t=10500 jiffies g=61977 q=1733)
NMI backtrace for cpu 0
CPU: 0 PID: 27163 Comm: syz-executor.2 Not tainted 5.2.0-rc4+ #46
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2625 [inline]
 rcu_sched_clock_irq.cold+0x4d1/0xbfd kernel/rcu/tree.c:2161
 update_process_times+0x32/0x80 kernel/time/timer.c:1639
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1298
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x33b/0xdd0 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1066
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806
 </IRQ>
RIP: 0010:write_comp_data+0x68/0x70 kernel/kcov.c:147
Code: 00 00 4e 8d 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 <c3> 0f 1f 80 00 00 00 00 55 40 0f b6 d6 40 0f b6 f7 31 ff 48 89 e5
RSP: 0018:ffff888058667420 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000002 RBX: 0000000000000003 RCX: ffffffff86125456
RDX: 0000000000000011 RSI: 0000000000000011 RDI: 0000000000000001
RBP: ffff888058667440 R08: ffff88805f35a180 R09: ffffed1015d06be0
R10: ffffed1015d06bdf R11: ffff8880ae835efb R12: ffffffff880d6400
R13: 0000000000000008 R14: 0000000000000000 R15: 0000000000000011
 xfrm_flowi_sport include/net/xfrm.h:851 [inline]
 __xfrm6_selector_match net/xfrm/xfrm_policy.c:214 [inline]
 xfrm_selector_match+0x426/0xfc0 net/xfrm/xfrm_policy.c:226
 xfrm_sk_policy_lookup+0x143/0x510 net/xfrm/xfrm_policy.c:2172
 xfrm_lookup_with_ifid+0x1de/0x1fc0 net/xfrm/xfrm_policy.c:3036
 xfrm_lookup net/xfrm/xfrm_policy.c:3173 [inline]
 xfrm_lookup_route+0x3b/0x1f0 net/xfrm/xfrm_policy.c:3184
 ip6_dst_lookup_flow+0x189/0x220 net/ipv6/ip6_output.c:1096
 inet6_csk_route_socket+0x85d/0xe80 net/ipv6/inet6_connection_sock.c:106
 inet6_csk_xmit+0x110/0x5d0 net/ipv6/inet6_connection_sock.c:121
 l2tp_xmit_core net/l2tp/l2tp_core.c:1033 [inline]
 l2tp_xmit_skb+0x1112/0x13e0 net/l2tp/l2tp_core.c:1135
 pppol2tp_sendmsg+0x4a2/0x6b0 net/l2tp/l2tp_ppp.c:325
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:665
 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2286
 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2381
 __do_sys_sendmmsg net/socket.c:2410 [inline]
 __se_sys_sendmmsg net/socket.c:2407 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2407
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459279
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdf3e439c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459279
RDX: 0800000000000059 RSI: 0000000020005fc0 RDI: 0000000000000006
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdf3e43a6d4
R13: 00000000004c683e R14: 00000000004db7c0 R15: 00000000ffffffff