rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2669 jiffies s: 156993 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: 4274 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:cake_heap_get_backlog net/sched/sch_cake.c:1472 [inline]
RIP: 0010:cake_heapify+0x260/0x560 net/sched/sch_cake.c:1495
Code: f0 c1 e8 03 25 ff 03 00 00 41 83 e6 07 49 69 ce d0 98 01 00 48 03 0b 4c 8d b4 81 00 40 01 00 4c 89 f0 48 c1 e8 03 0f b6 04 10 <84> c0 0f 85 49 02 00 00 45 8b 36 44 89 f7 44 89 e6 e8 6a a3 23 f9
RSP: 0018:ffffc90000006f68 EFLAGS: 00000a03
RAX: 0000000000000000 RBX: ffff888046fb02d0 RCX: ffff8880436331a0
RDX: dffffc0000000000 RSI: 0000000000000e4c RDI: 0000000000000fff
RBP: 0000000000000e4c R08: ffffffff90af2487 R09: 1ffffffff215e490
R10: dffffc0000000000 R11: fffffbfff215e491 R12: 0000000000000000
R13: 0000000000000e4c R14: ffff888043647fec R15: 0000000000001c9a
FS:  000055558fb9b500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34119ff8 CR3: 000000005e350000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 cake_drop net/sched/sch_cake.c:1575 [inline]
 cake_enqueue+0x44c1/0x86a0 net/sched/sch_cake.c:1949
 qdisc_enqueue include/net/sch_generic.h:854 [inline]
 netem_dequeue+0xcbb/0x1390 net/sched/sch_netem.c:736
 dequeue_skb net/sched/sch_generic.c:295 [inline]
 qdisc_restart net/sched/sch_generic.c:400 [inline]
 __qdisc_run+0x25a/0x1660 net/sched/sch_generic.c:418
 __dev_xmit_skb net/core/dev.c:3995 [inline]
 __dev_queue_xmit+0x1121/0x3810 net/core/dev.c:4337
 dev_queue_xmit include/linux/netdevice.h:3051 [inline]
 tipc_l2_send_msg+0x2f0/0x3b0 net/tipc/bearer.c:518
 tipc_bearer_xmit_skb+0x2a9/0x3f0 net/tipc/bearer.c:577
 tipc_disc_timeout+0x5e1/0x740 net/tipc/discover.c:338
 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x56c/0x810 kernel/time/timer.c:2023
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
 handle_softirqs+0x291/0x910 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 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:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:215
Code: 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d 90 f0 9d 0c 48 89 de 5b e9 77 5d 50 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d 24 4e 80 7e 65 8b 15 25 4e 80 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc90004637558 EFLAGS: 00000246
RAX: ffffffff81becd27 RBX: 0000000000000000 RCX: ffff88807dc3bc00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004637870 R08: ffffea0001c45633 R09: 1ffffd4000388ac6
R10: dffffc0000000000 R11: fffff94000388ac7 R12: 00007f913c4e9000
R13: ffffea0001c45600 R14: ffffea0001c45600 R15: dffffc0000000000
 mm_counter include/linux/mm.h:2223 [inline]
 copy_present_pte mm/memory.c:976 [inline]
 copy_pte_range mm/memory.c:1091 [inline]
 copy_pmd_range mm/memory.c:1177 [inline]
 copy_pud_range mm/memory.c:1214 [inline]
 copy_p4d_range mm/memory.c:1238 [inline]
 copy_page_range+0x14c7/0x3a60 mm/memory.c:1332
 dup_mmap kernel/fork.c:703 [inline]
 dup_mm kernel/fork.c:1547 [inline]
 copy_mm+0xeb0/0x1680 kernel/fork.c:1596
 copy_process+0x19a6/0x40c0 kernel/fork.c:2357
 kernel_clone+0x24b/0x900 kernel/fork.c:2764
 __do_sys_clone kernel/fork.c:2905 [inline]
 __se_sys_clone kernel/fork.c:2889 [inline]
 __x64_sys_clone+0x1a7/0x220 kernel/fork.c:2889
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f913cdc58d2
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007fffed1d7540 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fffed1d7540 RCX: 00007f913cdc58d2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007fffed1d76cc R08: 0000000000000000 R09: 0000000000000001
R10: 000055558fb9b7d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 000000000005e234 R15: 00007fffed1d7720
 </TASK>