rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2664 jiffies s: 30593 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 16904 Comm: syz.4.3553 Not tainted 6.1.147-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x80 kernel/kcov.c:314
Code: 28 4d 39 ca 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 03 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 <48> 8b 04 24 65 48 8b 15 f4 a4 81 7e 65 8b 0d f5 a4 81 7e 81 e1 00
RSP: 0018:ffffc90000007538 EFLAGS: 00000246
RAX: ffffffff885042ae RBX: 0000000000000000 RCX: 0000000000000100
RDX: ffff8880587d1dc0 RSI: 00000000000001bb RDI: 0000000000000fff
RBP: 00000000000001bb R08: dffffc0000000000 R09: fffffbfff215ba90
R10: fffffbfff215ba90 R11: 1ffffffff215ba8f R12: 0000000000000000
R13: 00000000000001bb R14: 00000000000001bb R15: ffff8880708c6f68
FS:  000055555ed53500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3fe1ce56c0 CR3: 0000000072ac5000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 cake_heapify+0x1b6/0x6a0 net/sched/sch_cake.c:1494
 cake_drop net/sched/sch_cake.c:1575 [inline]
 cake_enqueue+0x305a/0x7ee0 net/sched/sch_cake.c:1945
 qdisc_enqueue include/net/sch_generic.h:816 [inline]
 netem_dequeue+0xcfc/0x13c0 net/sched/sch_netem.c:737
 dequeue_skb net/sched/sch_generic.c:292 [inline]
 qdisc_restart net/sched/sch_generic.c:397 [inline]
 __qdisc_run+0x247/0x15f0 net/sched/sch_generic.c:415
 qdisc_run+0xc2/0x230 include/net/pkt_sched.h:126
 net_tx_action+0x764/0x920 net/core/dev.c:5166
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__syscall_enter_from_user_work kernel/entry/common.c:97 [inline]
RIP: 0010:syscall_enter_from_user_mode+0x2a/0x80 kernel/entry/common.c:118
Code: 41 56 53 48 89 f3 49 89 fe 48 8b 7c 24 10 e8 ed fa ff ff 66 90 66 90 e8 c4 fb 70 f7 e8 3f fa 70 f7 fb 65 48 8b 05 b6 46 ec 75 <48> 8b 70 08 40 f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 21 a3 57 f7 48
RSP: 0018:ffffc900038c7f08 EFLAGS: 00000286
RAX: ffff8880587d1dc0 RBX: 00000000000000e6 RCX: b20c5d8091beec00
RDX: dffffc0000000000 RSI: ffffffff8a8c0460 RDI: ffffffff8adef320
RBP: ffffc900038c7f48 R08: dffffc0000000000 R09: fffffbfff1c3e976
R10: fffffbfff1c3e976 R11: 1ffffffff1c3e975 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc900038c7f58 R15: 0000000000000000
 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f59a3dc14a5
Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8
RSP: 002b:00007ffc6a867f50 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 00007f59a3fb5fa0 RCX: 00007f59a3dc14a5
RDX: 00007ffc6a867f90 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f59a3fb7da0 R08: 0000000000000000 R09: 00079991c4b104b1
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000001048da
R13: 00007f59a3fb6090 R14: ffffffffffffffff R15: 00007ffc6a8680d0
 </TASK>