rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=90e/1/0x4000000000000004 softirq=42144/42147 fqs=5249 
	(t=10502 jiffies g=66581 q=2138)
NMI backtrace for cpu 0
CPU: 0 PID: 21297 Comm: syz-executor.0 Not tainted 5.3.0-rc6-next-20190830 #75
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/0xc12 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:1504 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1566
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1628
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1106 [inline]
 smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1131
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
RIP: 0010:__list_add include/linux/list.h:63 [inline]
RIP: 0010:list_add_tail include/linux/list.h:93 [inline]
RIP: 0010:list_move_tail include/linux/list.h:214 [inline]
RIP: 0010:hhf_dequeue+0x697/0xa20 net/sched/sch_hhf.c:439
Code: 31 ff 89 c6 88 45 b0 e8 d7 e7 a6 fb 0f b6 75 b0 40 84 f6 0f 84 c6 f9 ff ff e8 85 e6 a6 fb 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 <0f> 85 08 03 00 00 48 89 d8 49 89 9d 98 03 00 00 48 c1 e8 03 42 80
RSP: 0018:ffff8880ae809518 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff11012ff4273 RBX: ffff888097fa12f8 RCX: ffffffff85cb6f79
RDX: 0000000000000100 RSI: ffffffff85cb6f8b RDI: 0000000000000001
RBP: ffff8880ae809568 R08: ffff8880a40a0300 R09: fffffbfff14ed341
R10: ffff8880a40a0c68 R11: ffff8880a40a0300 R12: dffffc0000000000
R13: ffff888097fa1000 R14: ffff888097fa1398 R15: ffff888097fa1390
 dequeue_skb net/sched/sch_generic.c:258 [inline]
 qdisc_restart net/sched/sch_generic.c:361 [inline]
 __qdisc_run+0x1e7/0x19d0 net/sched/sch_generic.c:379
 __dev_xmit_skb net/core/dev.c:3533 [inline]
 __dev_queue_xmit+0x16f1/0x37c0 net/core/dev.c:3838
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902
 neigh_hh_output include/net/neighbour.h:500 [inline]
 neigh_output include/net/neighbour.h:509 [inline]
 ip6_finish_output2+0xf58/0x2550 net/ipv6/ip6_output.c:116
 __ip6_finish_output+0x444/0xaa0 net/ipv6/ip6_output.c:142
 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip6_output+0x235/0x7f0 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ndisc_send_skb+0xf29/0x14a0 net/ipv6/ndisc.c:505
 ndisc_send_rs+0x134/0x6d0 net/ipv6/ndisc.c:699
 addrconf_rs_timer+0x30f/0x680 net/ipv6/addrconf.c:3879
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1771 [inline]
 __run_timers kernel/time/timer.c:1738 [inline]
 run_timer_softirq+0x6c0/0x17f0 kernel/time/timer.c:1784
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1133
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 </IRQ>
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x54/0x90 kernel/locking/spinlock.c:199
Code: c0 b0 ed f2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 33 48 83 3d 55 63 af 01 00 74 20 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 12 d7 0a fa 65 8b 05 93 73 be 78 85 c0 74 06 41
RSP: 0018:ffff888094ff7910 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11e5db6 RBX: ffff8880a40a0300 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffff8880a40a0b9c
RBP: ffff888094ff7918 R08: ffff8880a40a0300 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880ae8348c0
R13: ffff88808c6f0100 R14: 0000000000000000 R15: 0000000000000000
 finish_lock_switch kernel/sched/core.c:3004 [inline]
 finish_task_switch+0x147/0x720 kernel/sched/core.c:3104
 context_switch kernel/sched/core.c:3268 [inline]
 __schedule+0x776/0x17a0 kernel/sched/core.c:3937
 schedule+0xd9/0x260 kernel/sched/core.c:4004
 pipe_wait+0x11c/0x1f0 fs/pipe.c:117
 splice_from_pipe_next.part.0+0x9d/0x300 fs/splice.c:564
 splice_from_pipe_next fs/splice.c:543 [inline]
 __splice_from_pipe+0x10f/0x7d0 fs/splice.c:622
 vmsplice_to_user fs/splice.c:1272 [inline]
 do_vmsplice.part.0+0x249/0x2b0 fs/splice.c:1350
 do_vmsplice fs/splice.c:1344 [inline]
 __do_sys_vmsplice+0x1bc/0x210 fs/splice.c:1371
 __se_sys_vmsplice fs/splice.c:1353 [inline]
 __x64_sys_vmsplice+0x97/0xf0 fs/splice.c:1353
 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4598e9
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:00007ffb3956cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000116
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000004598e9
RDX: 0000000000000001 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffb3956d6d4
R13: 00000000004c90c8 R14: 00000000004e0338 R15: 00000000ffffffff