rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=fc6/1/0x4000000000000002 softirq=42289/42290 fqs=1 
	(t=10501 jiffies g=61453 q=35)
rcu: rcu_preempt kthread starved for 10500 jiffies! g61453 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29040    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3384 [inline]
 __schedule+0x76e/0x17d0 kernel/sched/core.c:4056
 schedule+0xd9/0x260 kernel/sched/core.c:4123
 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1893
 rcu_gp_fqs_loop kernel/rcu/tree.c:1639 [inline]
 rcu_gp_kthread+0x9b2/0x18c0 kernel/rcu/tree.c:1799
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 19937 Comm: syz-executor.1 Not tainted 5.3.0+ #0
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+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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:2795 [inline]
 rcu_sched_clock_irq.cold+0x4fd/0xc0a kernel/rcu/tree.c:2244
 update_process_times+0x2d/0x70 kernel/time/timer.c:1724
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1299
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 </IRQ>
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:__read_seqcount_begin include/linux/seqlock.h:113 [inline]
RIP: 0010:raw_read_seqcount_begin include/linux/seqlock.h:148 [inline]
RIP: 0010:read_seqcount_begin include/linux/seqlock.h:165 [inline]
RIP: 0010:xfrm_state_find+0x1948/0x5040 net/xfrm/xfrm_state.c:1056
Code: f8 fe ff ff 48 8d 8d 50 ff ff ff 4c 8d 8d 40 ff ff ff 4c 8d 85 30 ff ff ff e8 94 dc fe ff e9 7d fb ff ff e8 2a 92 3c fb f3 90 <44> 8b 25 f1 2e 92 03 31 ff 44 89 e3 83 e3 01 89 de e8 52 93 3c fb
RSP: 0018:ffff88808b59ef50 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000040000 RBX: 0000000000000001 RCX: ffffc90008367000
RDX: 0000000000040000 RSI: ffffffff8635fd26 RDI: 0000000000000001
RBP: ffff88808b59f100 R08: ffff888083246200 R09: fffffbfff14ef145
R10: fffffbfff14ef144 R11: ffffffff8a778a27 R12: 0000000000000013
R13: 0000000000000000 R14: 000000000000000a R15: 0000000000000000
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2391 [inline]
 xfrm_tmpl_resolve+0x32a/0xc90 net/xfrm/xfrm_policy.c:2436
 xfrm_resolve_and_create_bundle+0x137/0x2670 net/xfrm/xfrm_policy.c:2727
 xfrm_lookup_with_ifid+0x278/0x1fb0 net/xfrm/xfrm_policy.c:3050
 xfrm_lookup net/xfrm/xfrm_policy.c:3174 [inline]
 xfrm_lookup_route+0x3b/0x1f0 net/xfrm/xfrm_policy.c:3185
 ip6_dst_lookup_flow+0x189/0x220 net/ipv6/ip6_output.c:1156
 inet6_csk_route_socket+0x85d/0xe80 net/ipv6/inet6_connection_sock.c:106
 inet6_csk_xmit+0x110/0x5ba net/ipv6/inet6_connection_sock.c:121
 l2tp_xmit_core net/l2tp/l2tp_core.c:1030 [inline]
 l2tp_xmit_skb+0x1112/0x13e0 net/l2tp/l2tp_core.c:1132
 pppol2tp_sendmsg+0x4af/0x6c0 net/l2tp/l2tp_ppp.c:325
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:657
 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2311
 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg net/socket.c:2439 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2439
 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a09
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:00007f1b6e1f5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459a09
RDX: 0800000000000059 RSI: 0000000020005fc0 RDI: 0000000000000007
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1b6e1f66d4
R13: 00000000004c71df R14: 00000000004dc9f8 R15: 00000000ffffffff