rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10501 ticks this GP) idle=18e/1/0x4000000000000002 softirq=18876/18876 fqs=0 rcu: (t=10502 jiffies g=15117 q=1029) rcu: rcu_preempt kthread starved for 10503 jiffies! g15117 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt I29024 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2844 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3485 schedule+0x92/0x180 kernel/sched/core.c:3529 schedule_timeout+0x4db/0xfd0 kernel/time/timer.c:1803 rcu_gp_fqs_loop kernel/rcu/tree.c:1948 [inline] rcu_gp_kthread+0x956/0x17a0 kernel/rcu/tree.c:2105 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 0 CPU: 0 PID: 9825 Comm: syz-executor.4 Not tainted 5.0.0+ #118 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:1211 print_cpu_stall kernel/rcu/tree.c:1348 [inline] check_cpu_stall kernel/rcu/tree.c:1422 [inline] rcu_pending kernel/rcu/tree.c:3018 [inline] rcu_check_callbacks.cold+0x500/0xa4a kernel/rcu/tree.c:2521 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:cpu_relax arch/x86/include/asm/processor.h:666 [inline] RIP: 0010:virt_spin_lock arch/x86/include/asm/qspinlock.h:84 [inline] RIP: 0010:native_queued_spin_lock_slowpath+0x132/0x970 kernel/locking/qspinlock.c:337 Code: 00 00 00 48 8b 45 d0 65 48 33 04 25 28 00 00 00 0f 85 a2 06 00 00 48 81 c4 98 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 f3 90 73 ff ff ff 8b 45 98 4c 8d 65 d8 3d 00 01 00 00 0f 84 e5 00 00 RSP: 0018:ffff8880694ef090 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffffe8ffffc75060 RCX: ffffffff81579127 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffe8ffffc75060 RBP: ffff8880694ef150 R08: 1ffffd1ffff8ea0c R09: fffff91ffff8ea0d R10: fffff91ffff8ea0c R11: ffffe8ffffc75063 R12: 0000000000000001 R13: 0000000000000003 R14: fffff91ffff8ea0c R15: 000000000000000b pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:653 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:50 [inline] queued_spin_lock include/asm-generic/qspinlock.h:90 [inline] do_raw_spin_lock+0x20e/0x2e0 kernel/locking/spinlock_debug.c:113 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_lock+0x37/0x40 kernel/locking/spinlock.c:144 spin_lock include/linux/spinlock.h:329 [inline] nf_ct_add_to_unconfirmed_list net/netfilter/nf_conntrack_core.c:487 [inline] init_conntrack.isra.0+0xa07/0x1170 net/netfilter/nf_conntrack_core.c:1478 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1519 [inline] nf_conntrack_in+0xd93/0x1410 net/netfilter/nf_conntrack_core.c:1679 ipv6_conntrack_local+0x1e/0x30 net/netfilter/nf_conntrack_proto.c:194 nf_hook_entry_hookfn include/linux/netfilter.h:119 [inline] nf_hook_slow+0xbf/0x1f0 net/netfilter/core.c:511 nf_hook include/linux/netfilter.h:244 [inline] NF_HOOK include/linux/netfilter.h:287 [inline] ip6_xmit+0x11c6/0x20c0 net/ipv6/ip6_output.c:275 inet6_csk_xmit+0x2fb/0x5d0 net/ipv6/inet6_connection_sock.c:139 __tcp_transmit_skb+0x1a32/0x3750 net/ipv4/tcp_output.c:1159 tcp_transmit_skb net/ipv4/tcp_output.c:1175 [inline] tcp_connect+0x2e43/0x4330 net/ipv4/tcp_output.c:3538 tcp_v6_connect+0x15c3/0x2180 net/ipv6/tcp_ipv6.c:319 __inet_stream_connect+0x83f/0xea0 net/ipv4/af_inet.c:655 inet_stream_connect+0x58/0xa0 net/ipv4/af_inet.c:719 __sys_connect+0x266/0x330 net/socket.c:1685 __do_sys_connect net/socket.c:1696 [inline] __se_sys_connect net/socket.c:1693 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1693 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457f29 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:00007f051dbfcc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457f29 RDX: 000000000000001c RSI: 0000000020000080 RDI: 0000000000000006 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f051dbfd6d4 R13: 00000000004be35b R14: 00000000004ceae8 R15: 00000000ffffffff