rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=a62/1/0x4000000000000002 softirq=37462/37463 fqs=4406 rcu: (t=10500 jiffies g=48821 q=2806) NMI backtrace for cpu 1 CPU: 1 PID: 20175 Comm: syz-executor.5 Not tainted 5.1.0-rc2+ #151 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:atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] RIP: 0010:virt_spin_lock arch/x86/include/asm/qspinlock.h:83 [inline] RIP: 0010:native_queued_spin_lock_slowpath+0xaa/0x9f0 kernel/locking/qspinlock.c:334 Code: 0f 1f 44 00 00 49 89 fe 49 89 fd 41 bc 01 00 00 00 49 c1 ee 03 41 83 e5 07 48 b8 00 00 00 00 00 fc ff df 49 01 c6 41 83 c5 03 04 00 00 00 48 89 df e8 d9 2d 50 00 41 0f b6 06 41 38 c5 7c 08 RSP: 0018:ffff8880a5bf6c70 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffffe8ffffd75f38 RCX: ffffffff81581bb7 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffe8ffffd75f38 RBP: ffff8880a5bf6d30 R08: 1ffffd1ffffaebe7 R09: fffff91ffffaebe8 R10: fffff91ffffaebe7 R11: ffffe8ffffd75f3b R12: 0000000000000001 R13: 0000000000000003 R14: fffff91ffffaebe7 R15: 0000000000002274 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:654 [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 sctp_v6_xmit+0x313/0x660 net/sctp/ipv6.c:232 sctp_packet_transmit+0x1bc4/0x36f0 net/sctp/output.c:641 sctp_packet_singleton net/sctp/outqueue.c:787 [inline] sctp_outq_flush_ctrl.constprop.0+0x6d4/0xd50 net/sctp/outqueue.c:918 sctp_outq_flush+0xe8/0x2780 net/sctp/outqueue.c:1200 sctp_outq_uncork+0x6c/0x80 net/sctp/outqueue.c:772 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1820 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1220 [inline] sctp_do_sm+0x559/0x53e0 net/sctp/sm_sideeffect.c:1191 sctp_primitive_ASSOCIATE+0x9d/0xd0 net/sctp/primitive.c:88 __sctp_connect+0x8cd/0xce0 net/sctp/socket.c:1226 __sctp_setsockopt_connectx+0x133/0x1a0 net/sctp/socket.c:1349 sctp_setsockopt_connectx_old net/sctp/socket.c:1365 [inline] sctp_setsockopt net/sctp/socket.c:4656 [inline] sctp_setsockopt+0x22cc/0x6d20 net/sctp/socket.c:4620 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3120 __sys_setsockopt+0x180/0x280 net/socket.c:2046 __do_sys_setsockopt net/socket.c:2057 [inline] __se_sys_setsockopt net/socket.c:2054 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:2054 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4582b9 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:00007f5ccbc6fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004582b9 RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000006 RBP: 000000000073bf00 R08: 000000000000001c R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 00007f5ccbc706d4 R13: 00000000004cd198 R14: 00000000004dafa0 R15: 00000000ffffffff