rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=2cb/1/0x4000000000000000 softirq=44175/44176 fqs=392 (t=10502 jiffies g=57241 q=417) rcu: rcu_preempt kthread starved for 9639 jiffies! g57241 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:26040 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: 11278 Comm: syz.2.1625 Not tainted 5.15.165-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 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:1686 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 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:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline] RIP: 0010:rcu_is_watching+0x2d/0xa0 kernel/rcu/tree.c:1123 Code: 56 53 65 ff 05 ec 56 97 7e e8 3f 48 c8 08 89 c3 83 f8 08 73 72 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 00 38 3b 8c 4c 89 f0 <48> c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 60 11 5f 00 48 c7 c3 RSP: 0018:ffffc90002ff7a40 EFLAGS: 00000297 RAX: ffffffff8c3b3808 RBX: 0000000000000001 RCX: ffffffff812f0bb2 RDX: ffff888027f43b80 RSI: ffffffff8ad8f7a0 RDI: ffffffff8ad8f760 RBP: ffffc90002ff7c01 R08: ffffffff812f0bda R09: fffffbfff1bd2a56 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 1ffff11004fe8a61 R14: ffffffff8c3b3808 R15: dffffc0000000000 trace_x86_fpu_regs_activated arch/x86/include/asm/trace/fpu.h:57 [inline] fpregs_activate+0x84/0x1c0 arch/x86/include/asm/fpu/internal.h:451 fpregs_mark_activate+0x23/0x80 arch/x86/kernel/fpu/core.c:429 restore_fpregs_from_user arch/x86/kernel/fpu/signal.c:299 [inline] __fpu_restore_sig arch/x86/kernel/fpu/signal.c:334 [inline] fpu__restore_sig+0x83c/0x1100 arch/x86/kernel/fpu/signal.c:466 restore_sigcontext+0x638/0x710 arch/x86/kernel/signal.c:139 __do_sys_rt_sigreturn+0x190/0x250 arch/x86/kernel/signal.c:674 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f5670deaeb7 Code: ff ff 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 RSP: 002b:00007f566f2670e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007f5670f86f88 RCX: 00007f5670deaeb9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5670f86f88 RBP: 00007f5670f86f80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5670f86f8c R13: 0000000000000000 R14: 00007fff3239bee0 R15: 00007fff3239bfc8