rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10499 ticks this GP) idle=3a2/1/0x4000000000000002 softirq=58216/58216 fqs=0 rcu: (t=10502 jiffies g=77249 q=30) rcu: rcu_preempt kthread starved for 10503 jiffies! g77249 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt I29304 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_timeout+0x4db/0xfd0 kernel/time/timer.c:1803 rcu_gp_fqs_loop kernel/rcu/tree.c:1971 [inline] rcu_gp_kthread+0x962/0x17b0 kernel/rcu/tree.c:2128 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 1 CPU: 1 PID: 24637 Comm: syz-executor.2 Not tainted 5.1.0-rc6+ #154 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __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.c:1223 print_cpu_stall kernel/rcu/tree.c:1360 [inline] check_cpu_stall kernel/rcu/tree.c:1434 [inline] rcu_pending kernel/rcu/tree.c:3103 [inline] rcu_sched_clock_irq.cold+0x500/0xa4a kernel/rcu/tree.c:2544 update_process_times+0x32/0x80 kernel/time/timer.c:1635 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:161 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1271 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x33e/0xde0 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline] smp_apic_timer_interrupt+0x120/0x570 arch/x86/kernel/apic/apic.c:1060 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807 RIP: 0010:write_comp_data+0x1e/0x70 kernel/kcov.c:123 Code: 48 89 34 d1 48 89 11 5d c3 0f 1f 00 65 4c 8b 04 25 00 ee 01 00 65 8b 05 20 60 91 7e a9 00 01 1f 00 75 51 41 8b 80 e0 12 00 00 <83> f8 03 75 45 49 8b 80 e8 12 00 00 45 8b 80 e4 12 00 00 4c 8b 08 RSP: 0018:ffff888082f3ef58 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff860dc92d RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff888082f3ef60 R08: ffff888088e76140 R09: ffff888088e769e0 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000027 R14: 000000000000000a R15: 0000000000000000 __read_seqcount_begin include/linux/seqlock.h:114 [inline] raw_read_seqcount_begin include/linux/seqlock.h:148 [inline] read_seqcount_begin include/linux/seqlock.h:165 [inline] xfrm_state_find+0x190d/0x35d0 net/xfrm/xfrm_state.c:963 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2385 [inline] xfrm_tmpl_resolve+0x32a/0xc90 net/xfrm/xfrm_policy.c:2430 xfrm_resolve_and_create_bundle+0x137/0x2300 net/xfrm/xfrm_policy.c:2728 xfrm_lookup_with_ifid+0x278/0x1ce0 net/xfrm/xfrm_policy.c:3051 xfrm_lookup net/xfrm/xfrm_policy.c:3175 [inline] xfrm_lookup_route+0x3b/0x1f0 net/xfrm/xfrm_policy.c:3186 ip6_dst_lookup_flow+0x189/0x220 net/ipv6/ip6_output.c:1100 inet6_csk_route_socket+0x85d/0xf40 net/ipv6/inet6_connection_sock.c:110 inet6_csk_xmit+0x110/0x5d0 net/ipv6/inet6_connection_sock.c:125 l2tp_xmit_core net/l2tp/l2tp_core.c:1033 [inline] l2tp_xmit_skb+0x1114/0x13e0 net/l2tp/l2tp_core.c:1135 pppol2tp_sendmsg+0x4a2/0x6b0 net/l2tp/l2tp_ppp.c:329 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:661 ___sys_sendmsg+0x3e2/0x930 net/socket.c:2279 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2374 __do_sys_sendmmsg net/socket.c:2403 [inline] __se_sys_sendmmsg net/socket.c:2400 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2400 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2469894c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458da9 RDX: 0800000000000059 RSI: 0000000020005fc0 RDI: 0000000000000005 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f24698956d4 R13: 00000000004c5fac R14: 00000000004da760 R15: 00000000ffffffff