rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=23785, q=354 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294964266-4294953764), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g23785 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 rcu: Possible timer handling issue on cpu=0 timer-softirq=10486 rcu: rcu_preempt kthread starved for 10502 jiffies! g23785 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->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 stack:28248 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1568/0x5290 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:advance_sched+0x178/0xc90 net/sched/sch_taprio.c:933 Code: db 74 29 49 8d 7c 24 c0 be ff ff ff ff e8 00 b2 f4 01 89 c3 31 ff 89 c6 e8 45 ac 1a f8 85 db 0f 84 ab 06 00 00 e8 f8 a7 1a f8 05 e8 f1 a7 1a f8 4d 8d 74 24 f0 4c 89 f1 48 c1 e9 03 48 b8 00 RSP: 0018:ffffc90000007c70 EFLAGS: 00000006 RAX: ffffffff89a992d8 RBX: 0000000000000001 RCX: ffffffff8e494ec0 RDX: 0000000000010000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000000f7c R12: ffff88801af8b300 R13: ffff88801af8b000 R14: dffffc0000000000 R15: ffff888031046000 FS: 0000000000000000(0000) GS:ffff8881254b0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f83507d4ff8 CR3: 0000000029fbc000 CR4: 00000000003526f0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1785 [inline] __hrtimer_run_queues+0x529/0xc30 kernel/time/hrtimer.c:1849 hrtimer_interrupt+0x42b/0x1010 kernel/time/hrtimer.c:1911 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x102/0x3d0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: 44 7b 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 38 2b 00 fb f4 7c e8 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e407dc0 EFLAGS: 00000246 RAX: 00000000000cd339 RBX: ffffffff8199661d RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8dee2508 RDI: ffffffff8c276500 RBP: ffffffff8e407eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff90109070 R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 0000000000000000 arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1bd/0x500 kernel/sched/idle.c:332 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430 rest_init+0x2de/0x300 init/main.c:757 start_kernel+0x380/0x3d0 init/main.c:1206 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147