rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=27b/1/0x4000000000000000 softirq=35274/35279 fqs=4754 
	(t=10500 jiffies g=50301 q=2297)
NMI backtrace for cpu 0
CPU: 0 PID: 10924 Comm: syz.0.1285 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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+0x22f/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31d/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+0x6ea/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+0x4b4/0xb70 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 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_heap_get_backlog net/sched/sch_cake.c:1472 [inline]
RIP: 0010:cake_heapify+0x25e/0x6a0 net/sched/sch_cake.c:1495
Code: 00 41 83 e6 07 49 69 ce d0 98 01 00 49 03 0f 4c 8d b4 81 00 40 01 00 4c 89 f0 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 5d 03 00 00 <45> 8b 36 44 89 f7 44 89 e6 e8 b4 be 64 f9 45 39 e6 44 0f 47 eb 45
RSP: 0018:ffffc9000331eec0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000001d4c RCX: ffff888040466340
RDX: dffffc0000000000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: 0000000000000ea5 R08: ffffffff901d418f R09: 1ffffffff203a831
R10: dffffc0000000000 R11: fffffbfff203a832 R12: 0000000000000000
R13: 0000000000000ea5 R14: ffff88804047b1e4 R15: ffff88804ba302d0
 cake_drop net/sched/sch_cake.c:1575 [inline]
 cake_enqueue+0x33d9/0x7fc0 net/sched/sch_cake.c:1949
 cbs_child_enqueue net/sched/sch_cbs.c:95 [inline]
 cbs_enqueue_soft+0x1a8/0x270 net/sched/sch_cbs.c:128
 dev_qdisc_enqueue+0x48/0x210 net/core/dev.c:3865
 __dev_xmit_skb net/core/dev.c:3949 [inline]
 __dev_queue_xmit+0xc25/0x2f80 net/core/dev.c:4266
 tipc_l2_send_msg+0x30a/0x3c0 net/tipc/bearer.c:518
 tipc_bearer_xmit_skb+0x292/0x3c0 net/tipc/bearer.c:577
 tipc_disc_reset+0x53f/0x850 net/tipc/discover.c:419
 tipc_l2_device_event+0x40c/0x5b0 net/tipc/bearer.c:-1
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
 call_netdevice_notifiers_mtu net/core/dev.c:2111 [inline]
 dev_set_mtu_ext+0x45f/0x680 net/core/dev.c:9021
 dev_set_mtu+0x41/0xc0 net/core/dev.c:9042
 dev_ifsioc+0x459/0xd50 net/core/dev_ioctl.c:331
 dev_ioctl+0x545/0xe30 net/core/dev_ioctl.c:572
 sock_do_ioctl+0x245/0x320 net/socket.c:1161
 sock_ioctl+0x4d2/0x710 net/socket.c:1266
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f059ec6a799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f059cec4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f059eee3fa0 RCX: 00007f059ec6a799
RDX: 0000200000002280 RSI: 0000000000008922 RDI: 0000000000000004
RBP: 00007f059ed00c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f059eee4038 R14: 00007f059eee3fa0 R15: 00007ffc42746d38
 </TASK>
vkms_vblank_simulate: vblank timer overrun