rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=1d14/1/0x4000000000000000 softirq=26963/26964 fqs=30
	(t=10502 jiffies g=29789 q=1273 ncpus=2)
rcu: rcu_preempt kthread starved for 10424 jiffies! g29789 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27424 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:741
CPU: 0 PID: 4264 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:cake_heap_get_backlog net/sched/sch_cake.c:1470 [inline]
RIP: 0010:cake_heapify+0x1fc/0x6a0 net/sched/sch_cake.c:1495
Code: 00 43 8d 5c 36 02 e8 03 8d 2f f9 89 d8 48 8b 0c 24 4c 8d 34 41 4c 89 f0 48 c1 e8 03 48 ba 00 00 00 00 00 fc ff df 0f b6 04 10 <84> c0 0f 85 90 03 00 00 45 0f b7 36 48 8b 44 24 10 80 3c 10 00 4c
RSP: 0018:ffffc90000006f60 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: 0000000000001a30 RCX: ffff8880772502d8
RDX: dffffc0000000000 RSI: 0000000000000d17 RDI: 0000000000000fff
RBP: 0000000000000d17 R08: dffffc0000000000 R09: fffffbfff215c47f
R10: fffffbfff215c47f R11: 1ffffffff215c47e R12: 0000000000000000
R13: 0000000000000d17 R14: ffff888077253738 R15: ffff88805dfc7ac4
FS:  000055555efdb500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd735cc020 CR3: 000000005dcf2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 cake_drop net/sched/sch_cake.c:1575 [inline]
 cake_enqueue+0x3195/0x7bc0 net/sched/sch_cake.c:1948
 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
 __dev_xmit_skb net/core/dev.c:3970 [inline]
 __dev_queue_xmit+0x107e/0x3760 net/core/dev.c:4312
 dev_queue_xmit include/linux/netdevice.h:3051 [inline]
 tipc_l2_send_msg+0x30f/0x3d0 net/tipc/bearer.c:518
 tipc_bearer_xmit_skb+0x2a9/0x3f0 net/tipc/bearer.c:577
 tipc_disc_timeout+0x568/0x6b0 net/tipc/discover.c:338
 call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1820
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 3e 18 42 f7 48 89 df e8 96 dd 42 f7 e8 21 d1 65 f7 fb bf 01 00 00 00 <e8> e6 5a 36 f7 65 8b 05 e7 13 e1 75 85 c0 74 02 5b c3 e8 34 25 df
RSP: 0018:ffffc90003ca78b8 EFLAGS: 00000286
RAX: d19bd48e5851c600 RBX: ffff888078f29660 RCX: d19bd48e5851c600
RDX: dffffc0000000000 RSI: ffffffff8a8c0300 RDI: 0000000000000001
RBP: ffffc90003ca7b70 R08: dffffc0000000000 R09: fffffbfff215c44a
R10: fffffbfff215c44a R11: 1ffffffff215c449 R12: dffffc0000000000
R13: 1ffff1100f1e52cb R14: ffff888078f29658 R15: ffff888078f29660
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 filemap_remove_folio+0xf5/0x2c0 mm/filemap.c:256
 truncate_inode_folio+0x59/0x70 mm/truncate.c:195
 shmem_undo_range+0x4d2/0x2050 mm/shmem.c:942
 shmem_truncate_range mm/shmem.c:1062 [inline]
 shmem_evict_inode+0x248/0xa40 mm/shmem.c:1171
 evict+0x485/0x870 fs/inode.c:705
 do_unlinkat+0x377/0x560 fs/namei.c:4397
 __do_sys_unlink fs/namei.c:4438 [inline]
 __se_sys_unlink fs/namei.c:4436 [inline]
 __x64_sys_unlink+0x45/0x50 fs/namei.c:4436
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe00a98e157
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc287164e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe00a98e157
RDX: 00007ffc28716510 RSI: 00007ffc287165a0 RDI: 00007ffc287165a0
RBP: 00007ffc287165a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffc28717630
R13: 00007fe00aa11c05 R14: 000000000008bbb3 R15: 00007ffc28717670
 </TASK>