rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 1-...!: (1 GPs behind) idle=a23/1/0x4000000000000002 softirq=22120/22121 fqs=0
(t=10502 jiffies g=28293 q=20)
rcu: rcu_preempt kthread starved for 10503 jiffies! g28293 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:27008 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 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+0x6d8/0x1110 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:1818
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:1690 [inline]
__hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
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
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804
Code: be ff ff ff ff e8 ec 7c 55 08 85 c0 74 4a 4d 85 ff 75 66 e9 fe 00 00 00 48 89 df e8 46 e7 5e 08 e8 71 75 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 d9 0f fe ff 43 80 3c
RSP: 0018:ffffc90000d67ac8 EFLAGS: 00000282
RAX: 48c54867349f2e00 RBX: ffff8880b903a300 RCX: 48c54867349f2e00
RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: ffffffff8a59a240
RBP: 1ffff1101722760b R08: dffffc0000000000 R09: ffffed1017207461
R10: ffffed1017207461 R11: 1ffff11017207460 R12: ffff8880b913b048
R13: dffffc0000000000 R14: ffff8880b913adc8 R15: 0000000000000000
finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921
context_switch kernel/sched/core.c:5052 [inline]
__schedule+0x11c3/0x4390 kernel/sched/core.c:6395
schedule_idle+0x4a/0x90 kernel/sched/core.c:6506
do_idle+0x556/0x5b0 kernel/sched/idle.c:334
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
start_secondary+0x31f/0x430 arch/x86/kernel/smpboot.c:281
secondary_startup_64_no_verify+0xb1/0xbb