rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=10729, q=544 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10030 (4294958672-4294948642), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10030 jiffies! g10729 f0x2 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:26264 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__mod_timer+0x4/0xeb0 kernel/time/timer.c:1065 Code: 00 00 00 5b 41 5e eb 1e 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 20 01 RSP: 0018:ffffc90000167b98 EFLAGS: 00000246 RAX: 1ffff9200002cf7a RBX: ffff88801cec0000 RCX: ffff88801cec0000 RDX: 0000000000000004 RSI: 00000000ffffb725 RDI: ffffc90000167bc0 RBP: ffffc90000167c90 R08: ffffc90000167bff R09: ffffc90000167bf0 R10: dffffc0000000000 R11: fffff5200002cf80 R12: dffffc0000000000 R13: 1ffff9200002cf74 R14: ffffc90000167bc0 R15: 00000000ffffb725 schedule_timeout+0x155/0x290 kernel/time/sleep_timeout.c:98 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 80 Comm: kworker/1:1 Not tainted 6.13.0-rc7-syzkaller-00149-g9bffa1ad25b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 de 0f 3a f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 43 b6 a1 f5 65 8b 05 b4 f8 37 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc90000a188c0 EFLAGS: 00000206 RAX: 3e02692e14088200 RBX: 1ffff9200014311c RCX: ffffffff817b387a RDX: dffffc0000000000 RSI: ffffffff8c0a98e0 RDI: 0000000000000001 RBP: ffffc90000a18950 R08: ffffffff942a5957 R09: 1ffffffff2854b2a R10: dffffc0000000000 R11: fffffbfff2854b2b R12: dffffc0000000000 R13: 1ffff92000143118 R14: ffffc90000a188e0 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2eb5ffff CR3: 000000003345e000 CR4: 0000000000350ef0 Call Trace: dummy_timer+0x44d6/0x4620 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x59d/0xd30 kernel/time/hrtimer.c:1803 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1820 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline] RIP: 0010:__local_bh_enable_ip+0x170/0x200 kernel/softirq.c:396 Code: 8c e8 d4 63 67 0a 65 66 8b 05 b4 00 a2 7e 66 85 c0 75 5d bf 01 00 00 00 e8 0d be 0b 00 e8 68 67 45 00 fb 65 8b 05 78 00 a2 7e <85> c0 75 05 e8 f7 81 a8 ff 48 c7 44 24 20 0e 36 e0 45 49 c7 04 1c RSP: 0018:ffffc900023afa80 EFLAGS: 00000282 RAX: 0000000080000000 RBX: 1ffff92000475f54 RCX: ffffffff817b387a RDX: dffffc0000000000 RSI: ffffffff8c0a98e0 RDI: ffffffff8c5fb220 RBP: ffffc900023afb28 R08: ffffffff942a5957 R09: 1ffffffff2854b2a R10: dffffc0000000000 R11: fffffbfff2854b2b R12: dffffc0000000000 R13: 1ffff92000475f58 R14: ffffc900023afac0 R15: 0000000000000201 neigh_periodic_work+0xbcb/0xde0 net/core/neighbour.c:968 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244