rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=13b/1/0x4000000000000000 softirq=8715/8734 fqs=285 (t=10502 jiffies g=10133 q=717) rcu: rcu_preempt kthread starved for 9933 jiffies! g10133 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:26240 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 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 acpi_safe_halt drivers/acpi/processor_idle.c:108 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562 NMI backtrace for cpu 1 CPU: 1 PID: 4228 Comm: syz.4.110 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_dump_cpu_stacks+0x223/0x390 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x320/0x600 kernel/rcu/tree_stall.h:633 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0x8d9/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:pagefault_disabled include/linux/uaccess.h:259 [inline] RIP: 0010:__might_fault+0x38/0x110 mm/memory.c:5322 Code: 49 bc 00 00 00 00 00 fc ff df e8 33 a1 c6 ff 65 48 8b 1d 7b b6 48 7e 48 8d ab 88 17 00 00 48 89 e8 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 b3 00 00 00 8b 6d 00 31 ff 89 ee e8 64 a4 c6 ff 85 ed RSP: 0018:ffffc900030e79b0 EFLAGS: 00000a02 RAX: 0000000000000000 RBX: ffff888029a90000 RCX: ffff888029a90000 RDX: 0000000000000000 RSI: 000000000000008f RDI: ffffffff8a85e200 RBP: ffff888029a91788 R08: ffffffff812f3374 R09: ffffed1002fb1641 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000007 R14: 000000000000008f R15: ffffffff8a85e200 __copy_to_user include/linux/uaccess.h:143 [inline] save_xstate_epilog arch/x86/kernel/fpu/signal.c:104 [inline] copy_fpstate_to_sigframe+0x858/0xb40 arch/x86/kernel/fpu/signal.c:217 get_sigframe+0x378/0x4b0 arch/x86/kernel/signal.c:295 __setup_rt_frame arch/x86/kernel/signal.c:471 [inline] setup_rt_frame arch/x86/kernel/signal.c:780 [inline] handle_signal arch/x86/kernel/signal.c:824 [inline] arch_do_signal_or_restart+0x4ac/0x1890 arch/x86/kernel/signal.c:869 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f16970b9ff9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fffe5149c88 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007fffe5149db0 RCX: 00007f16970b9ff9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f1697272064 RBP: 00007f1697272064 R08: 0000000000000010 R09: 00007fffe5149f7f R10: 00007fffe5149d90 R11: 0000000000000246 R12: 000000000001c5d2 R13: 00007fffe5149d90 R14: 0000000000000032 R15: 000000000001c5a0