INFO: rcu_preempt self-detected stall on CPU
	1-...: (10499 ticks this GP) idle=bc6/140000000000001/0 softirq=19225/19225 fqs=0 
	 (t=10500 jiffies g=4769 c=4768 q=69)
rcu_preempt kthread starved for 10500 jiffies! g4769 c4768 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x402 ->cpu=0
rcu_preempt     I29776     8      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_timeout+0x43e/0xe10 kernel/time/timer.c:1744
 rcu_gp_kthread+0xbf4/0x1ec0 kernel/rcu/tree.c:2255
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
NMI backtrace for cpu 1
CPU: 1 PID: 8905 Comm: syz-executor.0 Not tainted 4.14.121 #15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x138/0x19c lib/dump_stack.c:53
 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x141/0x189 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:158 [inline]
 rcu_dump_cpu_stacks+0x186/0x1d2 kernel/rcu/tree.c:1396
 print_cpu_stall kernel/rcu/tree.c:1542 [inline]
 check_cpu_stall kernel/rcu/tree.c:1610 [inline]
 __rcu_pending kernel/rcu/tree.c:3390 [inline]
 rcu_pending kernel/rcu/tree.c:3452 [inline]
 rcu_check_callbacks.cold+0x43d/0xd0a kernel/rcu/tree.c:2792
 update_process_times+0x31/0x70 kernel/time/timer.c:1588
 tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:161
 tick_sched_timer+0x43/0x130 kernel/time/tick-sched.c:1219
 __run_hrtimer kernel/time/hrtimer.c:1220 [inline]
 __hrtimer_run_queues+0x270/0xbc0 kernel/time/hrtimer.c:1284
 hrtimer_interrupt+0x1d8/0x5d0 kernel/time/hrtimer.c:1318
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline]
 smp_apic_timer_interrupt+0x11c/0x5e0 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0x8e/0xa0 arch/x86/entry/entry_64.S:789
 </IRQ>
RIP: 0010:__read_seqcount_begin include/linux/seqlock.h:114 [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+0x1249/0x28a0 net/xfrm/xfrm_state.c:950
RSP: 0018:ffff888085cdefb8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000015 RBX: 0000000000000212 RCX: ffffc9000803e000
RDX: 0000000000040000 RSI: ffffffff854122d1 RDI: 0000000000000212
RBP: ffff888085cdf138 R08: ffff88808d1826c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880a8971d38
 xfrm_tmpl_resolve_one+0x1b0/0x7f0 net/xfrm/xfrm_policy.c:1394
 xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:1438 [inline]
 xfrm_resolve_and_create_bundle+0x219/0x2480 net/xfrm/xfrm_policy.c:1832
 xfrm_lookup+0x212/0x1920 net/xfrm/xfrm_policy.c:2164
 xfrm_lookup_route+0x38/0x1b0 net/xfrm/xfrm_policy.c:2284
 ip_route_output_flow+0x90/0xa0 net/ipv4/route.c:2599
 udp_sendmsg+0x14a1/0x1da0 net/ipv4/udp.c:1021
 udpv6_sendmsg+0x1356/0x2640 net/ipv6/udp.c:1193
 inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 ___sys_sendmsg+0x349/0x840 net/socket.c:2062
 __sys_sendmmsg+0x152/0x3a0 net/socket.c:2152
 SYSC_sendmmsg net/socket.c:2183 [inline]
 SyS_sendmmsg+0x35/0x60 net/socket.c:2178
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459279
RSP: 002b:00007f67cad8fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459279
RDX: 040000000000029a RSI: 0000000020000180 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f67cad906d4
R13: 00000000004c65fc R14: 00000000004db280 R15: 00000000ffffffff
INFO: rcu_sched detected stalls on CPUs/tasks:
	1-...: (10500 ticks this GP) idle=bc6/140000000000000/0 softirq=19225/19225 fqs=0 
	(detected by 0, t=10557 jiffies, g=2849, c=2848, q=4)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8905 Comm: syz-executor.0 Not tainted 4.14.121 #15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88808d1826c0 task.stack: ffff888085cd8000
RIP: 0010:__read_once_size include/linux/compiler.h:186 [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+0x1243/0x28a0 net/xfrm/xfrm_state.c:950
RSP: 0018:ffff888085cdefb8 EFLAGS: 00000246
RAX: 0000000000040000 RBX: 0000000000000212 RCX: ffffc9000803e000
RDX: 0000000000040000 RSI: ffffffff854122d1 RDI: 0000000000000212
RBP: ffff888085cdf138 R08: ffff88808d1826c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880a8971d38
FS:  00007f67cad90700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f911ebb3c50 CR3: 00000000a4e6b000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 xfrm_tmpl_resolve_one+0x1b0/0x7f0 net/xfrm/xfrm_policy.c:1394
 xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:1438 [inline]
 xfrm_resolve_and_create_bundle+0x219/0x2480 net/xfrm/xfrm_policy.c:1832
 xfrm_lookup+0x212/0x1920 net/xfrm/xfrm_policy.c:2164
 xfrm_lookup_route+0x38/0x1b0 net/xfrm/xfrm_policy.c:2284
 ip_route_output_flow+0x90/0xa0 net/ipv4/route.c:2599
 udp_sendmsg+0x14a1/0x1da0 net/ipv4/udp.c:1021
 udpv6_sendmsg+0x1356/0x2640 net/ipv6/udp.c:1193
 inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 ___sys_sendmsg+0x349/0x840 net/socket.c:2062
 __sys_sendmmsg+0x152/0x3a0 net/socket.c:2152
 SYSC_sendmmsg net/socket.c:2183 [inline]
 SyS_sendmmsg+0x35/0x60 net/socket.c:2178
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459279
RSP: 002b:00007f67cad8fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459279
RDX: 040000000000029a RSI: 0000000020000180 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f67cad906d4
R13: 00000000004c65fc R14: 00000000004db280 R15: 00000000ffffffff
Code: e8 d3 80 1b fc 85 db 41 bc f5 ff ff ff 0f 85 e9 00 00 00 e8 c0 80 1b fc 44 8b a5 68 ff ff ff e9 d8 00 00 00 e8 af 80 1b fc f3 90 <8b> 05 47 76 e5 02 a8 01 75 ef 89 85 f0 fe ff ff e9 66 f0 ff ff 
rcu_sched kthread starved for 10557 jiffies! g2849 c2848 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x402 ->cpu=0
rcu_sched       I29824     9      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_timeout+0x43e/0xe10 kernel/time/timer.c:1744
 rcu_gp_kthread+0xbf4/0x1ec0 kernel/rcu/tree.c:2255
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404