rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10752 ticks this GP) idle=da1/1/0x4000000000000000 softirq=12447/12449 fqs=292 (t=10500 jiffies g=15537 q=155) rcu: rcu_preempt kthread starved for 9912 jiffies! g15537 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:27536 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x9b/0x370 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: 5627 Comm: syz.4.326 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 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+0x6ea/0x1120 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:2021 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:1685 [inline] __hrtimer_run_queues+0x4ad/0xb70 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 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:get_current kernel/rcu/tree_plugin.h:397 [inline] RIP: 0010:rcu_preempt_read_enter kernel/rcu/tree_plugin.h:375 [inline] RIP: 0010:__rcu_read_lock+0x0/0x50 kernel/rcu/tree_plugin.h:398 Code: e9 1c fd ff ff 44 89 f1 80 e1 07 38 c1 0f 8c 22 fd ff ff 4c 89 f7 e8 ff b0 58 00 e9 15 fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 <53> 65 48 8b 1d 67 f2 9c 7e 48 81 c3 3c 04 00 00 48 89 d8 48 c1 e8 RSP: 0018:ffffc9000323fed8 EFLAGS: 00000246 RAX: ffffffff814faed7 RBX: 0000000000000000 RCX: 0000000000080000 RDX: ffffc9000e62a000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: 0000000000000001 R08: ffffffff8d89dc2f R09: 1ffffffff1b13b85 R10: dffffc0000000000 R11: fffffbfff1b13b86 R12: 0000000000000000 R13: 0000000000000000 R14: ffff8880269fd940 R15: 0000000000000027 rcu_read_lock include/linux/rcupdate.h:738 [inline] __task_pid_nr_ns+0x1c/0x420 kernel/pid.c:497 task_tgid_vnr include/linux/sched.h:1585 [inline] __ia32_sys_getpid+0x19/0x20 kernel/sys.c:945 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f6d5fcfd417 Code: 8d 3d fa 8a 0b 00 e8 58 1d fa ff e8 63 87 00 00 0f 1f 00 b8 68 00 00 00 0f 05 c3 0f 1f 84 00 00 00 00 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00 RSP: 002b:00007f6d5df5ca48 EFLAGS: 00000206 ORIG_RAX: 0000000000000027 RAX: ffffffffffffffda RBX: 00007f6d5df5cbb0 RCX: 00007f6d5fcfd417 RDX: 00007f6d5df5ca80 RSI: 00007f6d5df5cbb0 RDI: 0000000000000021 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f6d5ff7d038 R14: 00007f6d5ff7cfa0 R15: 00007fffc058ebf8 vkms_vblank_simulate: vblank timer overrun