rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=e9d/1/0x4000000000000000 softirq=29087/29089 fqs=4988 
	(t=10500 jiffies g=38885 q=1670)
NMI backtrace for cpu 1
CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x22d/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31f/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6ec/0x1120 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:2021
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4b0/0xb60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x397/0x8b0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:cake_drop net/sched/sch_cake.c:1571 [inline]
RIP: 0010:cake_enqueue+0x4497/0x8690 net/sched/sch_cake.c:1946
Code: 00 41 0f b7 1c 24 31 ff 89 de e8 84 76 62 f9 85 db 74 07 e8 9b 73 62 f9 eb 21 bb 00 10 00 00 0f b7 f3 4c 89 ff e8 a9 6a 01 00 <83> eb 01 72 07 e8 7f 73 62 f9 eb e9 e8 78 73 62 f9 48 ba 00 00 00
RSP: 0018:ffffc90000da6ec0 EFLAGS: 00000286
RAX: ffffffff8817fd74 RBX: 000000000000042d RCX: ffff888017a08000
RDX: 0000000000000100 RSI: 000000000000042d RDI: 000000000000042d
RBP: ffffc90000da7390 R08: ffffffff901ee1d7 R09: 1ffffffff203dc3a
R10: dffffc0000000000 R11: fffffbfff203dc3b R12: ffff88801fa7c2d8
R13: ffff88801fa78000 R14: 0000000000000500 R15: ffff88801fa782c0
 qdisc_enqueue include/net/sch_generic.h:842 [inline]
 netem_dequeue+0xd4c/0x1410 net/sched/sch_netem.c:737
 dequeue_skb net/sched/sch_generic.c:295 [inline]
 qdisc_restart net/sched/sch_generic.c:400 [inline]
 __qdisc_run+0x22f/0x14b0 net/sched/sch_generic.c:418
 __dev_xmit_skb net/core/dev.c:3955 [inline]
 __dev_queue_xmit+0xdce/0x2e50 net/core/dev.c:4266
 tipc_l2_send_msg+0x2eb/0x3a0 net/tipc/bearer.c:519
 tipc_bearer_xmit_skb+0x292/0x3c0 net/tipc/bearer.c:578
 tipc_disc_timeout+0x5e1/0x740 net/tipc/discover.c:338
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x56c/0x810 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x336/0x830 kernel/softirq.c:576
 run_ksoftirqd+0xa4/0x100 kernel/softirq.c:943
 smpboot_thread_fn+0x520/0x990 kernel/smpboot.c:164
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>