rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10499 ticks this GP) idle=e3e/1/0x4000000000000004 softirq=347156/347156 fqs=3549 
	(t=10500 jiffies g=528725 q=1220)
rcu: rcu_preempt kthread starved for 3371 jiffies! g528725 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29160    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xd9/0x260 kernel/sched/core.c:3947
 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1807
 rcu_gp_fqs_loop kernel/rcu/tree.c:1611 [inline]
 rcu_gp_kthread+0x9b2/0x18c0 kernel/rcu/tree.c:1768
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 0
CPU: 0 PID: 9914 Comm: syz-fuzzer Not tainted 5.3.0-rc8+ #0
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:2736 [inline]
 rcu_sched_clock_irq.cold+0x4dd/0xc13 kernel/rcu/tree.c:2183
 update_process_times+0x32/0x80 kernel/time/timer.c:1639
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1296
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
 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:hhf_dequeue+0x5a6/0xa20 net/sched/sch_hhf.c:438
Code: b5 ac 03 00 00 e8 ea 14 ac fb 49 8d bd 14 03 00 00 48 89 f8 48 c1 e8 03 42 0f b6 14 20 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 <84> d2 0f 85 3f 04 00 00 45 0f af b5 14 03 00 00 48 89 df 45 01 fe
RSP: 0000:ffff8880ae809218 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: ffff88809f2839b8 RCX: ffffffff85c65b39
RDX: 0000000000000000 RSI: ffffffff85c66006 RDI: ffff88809f2839d4
RBP: ffff8880ae809268 R08: ffff88809526c0c0 R09: 0000000000000000
R10: fffffbfff134afaf R11: ffff88809526c0c0 R12: dffffc0000000000
R13: ffff88809f2836c0 R14: 0000000000000000 R15: 0000000000000000
 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+0x16f1/0x3650 net/core/dev.c:3838
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902
 br_dev_queue_push_xmit+0x3f3/0x5c0 net/bridge/br_forward.c:52
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 br_forward_finish+0xfa/0x400 net/bridge/br_forward.c:65
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 __br_forward+0x641/0xb00 net/bridge/br_forward.c:109
 deliver_clone+0x61/0xc0 net/bridge/br_forward.c:125
 maybe_deliver+0x2c7/0x390 net/bridge/br_forward.c:181
 br_flood+0x13a/0x3d0 net/bridge/br_forward.c:223
 br_dev_xmit+0xd33/0x15a0 net/bridge/br_device.c:84
 __netdev_start_xmit include/linux/netdevice.h:4406 [inline]
 netdev_start_xmit include/linux/netdevice.h:4420 [inline]
 xmit_one net/core/dev.c:3280 [inline]
 dev_hard_start_xmit+0x1a3/0x9c0 net/core/dev.c:3296
 __dev_queue_xmit+0x2b15/0x3650 net/core/dev.c:3869
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902
 tipc_l2_send_msg+0x2ab/0x440 net/tipc/bearer.c:461
 tipc_bearer_xmit_skb+0x17e/0x370 net/tipc/bearer.c:503
 tipc_disc_timeout+0x933/0xd60 net/tipc/discover.c:332
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322
 expire_timers kernel/time/timer.c:1366 [inline]
 __run_timers kernel/time/timer.c:1685 [inline]
 __run_timers kernel/time/timer.c:1653 [inline]
 run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698
 __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:537 [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: 0033:0x45d280
Code: 48 8b 06 48 8b 4c 1e f8 48 89 07 48 89 4c 1f f8 c3 f3 0f 6f 06 f3 0f 6f 4c 1e f0 f3 0f 7f 07 f3 0f 7f 4c 1f f0 c3 f3 0f 6f 06 <f3> 0f 6f 4e 10 f3 0f 6f 54 1e e0 f3 0f 6f 5c 1e f0 f3 0f 7f 07 f3
RSP: 002b:000000c42c8ed6b0 EFLAGS: 00000283 ORIG_RAX: ffffffffffffff13
RAX: 0000000000929b8a RBX: 000000000000002f RCX: 0000000000000000
RDX: 000000000000002f RSI: 0000000000929b8a RDI: 000000c42bcb5000
RBP: 000000c42c8ed730 R08: 000000c42e75aab0 R09: 0000000000000000
R10: 0000000000c0de00 R11: 0000000000001800 R12: 000000c42bcb5000
R13: 00000000008e4763 R14: 0000000000000043 R15: 000000c42ea9d3c8