rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10616 ticks this GP) idle=865/1/0x4000000000000000 softirq=17546/17548 fqs=344 (t=10500 jiffies g=21973 q=235) rcu: rcu_preempt kthread starved for 9809 jiffies! g21973 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:27032 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: 5837 Comm: syz.0.554 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:lock_release+0x647/0x9a0 kernel/locking/lockdep.c:5647 Code: 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 4b c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25 28 00 00 00 <48> 3b 84 24 e0 00 00 00 0f 85 10 03 00 00 48 8d 65 d8 5b 41 5c 41 RSP: 0018:ffffc90003227be0 EFLAGS: 00000206 RAX: 23dd703b92fe4c00 RBX: 1ffff92000644f8e RCX: ffffc90003227c03 RDX: 0000000000000000 RSI: ffffffff8a8b3cc0 RDI: ffffffff8ad8f7c0 RBP: ffffc90003227d20 R08: dffffc0000000000 R09: fffffbfff1bd2a56 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000644f88 R13: 0000000000000246 R14: ffffc90003227c70 R15: dffffc0000000000 _copy_from_user+0x28/0x170 lib/usercopy.c:14 copy_from_user include/linux/uaccess.h:192 [inline] restore_altstack+0x9a/0x400 kernel/signal.c:4249 __do_sys_rt_sigreturn+0x19d/0x250 arch/x86/kernel/signal.c:677 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: 0033:0x7f6732d0af65 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 c6 57 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 1f 58 ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007ffcbd0dd9e0 EFLAGS: 00000293 RAX: fffffffffffffffc RBX: 00007f6732e74f80 RCX: 00007f6732d0af65 RDX: 00007ffcbd0dda20 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f6732e76a80 R08: 0000000000000000 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000293 R12: 000000000002d8e2 R13: 00007ffcbd0ddb40 R14: 00007ffcbd0ddb60 R15: ffffffffffffffff