rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (3 ticks this GP) idle=ff4c/1/0x4000000000000000 softirq=4950/4950 fqs=2 (t=21869 jiffies g=4929 q=393 ncpus=2) rcu: rcu_preempt kthread timer wakeup didn't happen for 21747 jiffies! g4929 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=1337 rcu: rcu_preempt kthread starved for 21748 jiffies! g4929 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 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:I stack:29352 pid: 16 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5182 [inline] __schedule+0xadf/0x52b0 kernel/sched/core.c:6494 schedule+0xda/0x1b0 kernel/sched/core.c:6570 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1657 rcu_gp_kthread+0x236/0x360 kernel/rcu/tree.c:1854 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.0.0-rc6-syzkaller-00009-g60891ec99e14 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 RIP: 0010:__this_cpu_preempt_check+0x0/0x20 lib/smp_processor_id.c:65 Code: e8 d1 d8 cb ff eb a2 0f 1f 00 0f 1f 44 00 00 48 c7 c6 40 04 49 8a 48 c7 c7 80 04 49 8a e9 78 fe ff ff 0f 1f 84 00 00 00 00 00 <55> 48 89 fd 0f 1f 44 00 00 48 89 ee 5d 48 c7 c7 c0 04 49 8a e9 57 RSP: 0018:ffffc900001e0c70 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 221e6d18987de8af RCX: ffffc900001e0cc8 RDX: 1ffff110023504fd RSI: 0000000000000000 RDI: ffffffff89ecaba0 RBP: 1ffff9200003c191 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000002 R14: ffff888011a827f0 R15: ffff888011a81d80 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000051f570 CR3: 000000002476a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:466 [inline] lock_release+0x3bb/0x780 kernel/locking/lockdep.c:5688 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x16/0x70 kernel/locking/spinlock.c:194 debug_object_deactivate lib/debugobjects.c:754 [inline] debug_object_deactivate+0x264/0x300 lib/debugobjects.c:720 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate kernel/time/hrtimer.c:481 [inline] __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x3f3/0xe40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline] RIP: 0010:acpi_safe_halt+0x6f/0xb0 drivers/acpi/processor_idle.c:113 Code: f7 84 db 74 06 5b e9 30 d9 f8 f7 e8 2b d9 f8 f7 e8 56 50 ff f7 66 90 e8 1f d9 f8 f7 0f 00 2d 88 9d d1 00 e8 13 d9 f8 f7 fb f4 <9c> 5b 81 e3 00 02 00 00 fa 31 ff 48 89 de e8 de d5 f8 f7 48 85 db RSP: 0018:ffffc90000177d20 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888011a81d80 RSI: ffffffff89832fdd RDI: 0000000000000000 RBP: ffff888012619864 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000001 R14: ffff888012619800 R15: ffff88801b8f0804 acpi_idle_do_entry drivers/acpi/processor_idle.c:555 [inline] acpi_idle_enter+0x524/0x6a0 drivers/acpi/processor_idle.c:692 cpuidle_enter_state+0x1ab/0xd30 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3e8/0x590 kernel/sched/idle.c:303 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:400 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:262 secondary_startup_64_no_verify+0xce/0xdb NMI backtrace for cpu 0 CPU: 0 PID: 1090 Comm: kworker/u4:5 Not tainted 6.0.0-rc6-syzkaller-00009-g60891ec99e14 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Workqueue: events_unbound toggle_allocation_gate Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x46/0x14f lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x206/0x250 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_dump_cpu_stacks+0x2c7/0x4d0 kernel/rcu/tree_stall.h:371 print_cpu_stall kernel/rcu/tree_stall.h:660 [inline] check_cpu_stall kernel/rcu/tree_stall.h:744 [inline] rcu_pending kernel/rcu/tree.c:3660 [inline] rcu_sched_clock_irq.cold+0x9f/0x79c kernel/rcu/tree.c:2342 update_process_times+0x11a/0x1a0 kernel/time/timer.c:1839 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:243 tick_sched_timer+0xee/0x120 kernel/time/tick-sched.c:1480 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:csd_lock_wait kernel/smp.c:414 [inline] RIP: 0010:smp_call_function_many_cond+0x5c3/0x1430 kernel/smp.c:988 Code: 89 ee e8 30 ad 0a 00 85 ed 74 48 48 8b 44 24 08 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 4f b0 0a 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 b5 0b 00 00 8b 43 08 31 RSP: 0018:ffffc90005687948 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9b3edc0 RCX: 0000000000000000 RDX: ffff88801fee3b00 RSI: ffffffff817158a1 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed1017367db9 R13: 0000000000000001 R14: dffffc0000000000 R15: 0000000000000001 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1154 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1302 [inline] text_poke_bp_batch+0x233/0x6c0 arch/x86/kernel/alternative.c:1490 text_poke_flush arch/x86/kernel/alternative.c:1660 [inline] text_poke_flush arch/x86/kernel/alternative.c:1657 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1667 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32f/0x410 kernel/jump_label.c:801 static_key_enable_cpuslocked+0x1b1/0x260 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate mm/kfence/core.c:811 [inline] toggle_allocation_gate+0x100/0x390 mm/kfence/core.c:803 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306