rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=db94/0/0x1 softirq=171665/171666 fqs=2 (detected by 0, t=10505 jiffies, g=251437, q=30 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.1.77-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:lock_acquire+0x1ec/0x5a0 kernel/locking/lockdep.c:5662 Code: 98 7e 45 31 c9 41 f7 c7 00 02 00 00 41 0f 94 c1 48 8b 7c 24 20 44 89 f6 8b 54 24 1c 48 8b 4c 24 30 4c 8b 44 24 38 6a 00 6a 00 75 10 ff 74 24 40 e8 e8 04 00 00 48 83 c4 20 48 c7 c7 40 fe eb RSP: 0018:ffffc900001e0b50 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffffc900001e0bc0 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8d12a740 RBP: ffffc900001e0ca8 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200003c174 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000046 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555556350978 CR3: 000000008cca4000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:318 [inline] rcu_read_lock include/linux/rcupdate.h:759 [inline] advance_sched+0x6ec/0x970 net/sched/sch_taprio.c:753 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [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 drivers/acpi/processor_idle.c:113 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:572 Code: ec f5 f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 24 a8 fc f6 0f 1f 44 00 00 e8 ca e8 f5 f6 0f 00 2d 43 8d b2 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 6b 56 4d f7 RSP: 0018:ffffc90000177b80 EFLAGS: 000002d3 RAX: ffffffff8a949256 RBX: 0000000000000000 RCX: ffff888012731dc0 RDX: 0000000000000000 RSI: ffffffff8aebecc0 RDI: ffffffff8b3d0dc0 RBP: ffffc90000177c10 R08: ffffffff8a949238 R09: ffffed10024e63b9 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200002ef70 R13: ffff888016305804 R14: ffffc90000177ba0 R15: dffffc0000000000 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:709 cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3ce/0x680 kernel/sched/idle.c:303 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xcf/0xdb rcu: rcu_preempt kthread starved for 10495 jiffies! g251437 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:26648 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x2d2/0x1120 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 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: CPU: 0 PID: 26134 Comm: kworker/u4:13 Not tainted 6.1.77-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline] RIP: 0010:smp_call_function_many_cond+0x1fb0/0x3460 kernel/smp.c:998 Code: 2f 44 89 ee 83 e6 01 31 ff e8 ec 42 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 77 3f 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff RSP: 0018:ffffc90004d075a0 EFLAGS: 00000293 RAX: ffffffff817f3bcb RBX: 1ffff11017328031 RCX: ffff888029858000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90004d07980 R08: ffffffff817f3b94 R09: fffffbfff2092245 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000 R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b9940188 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30d21000 CR3: 000000000ce8e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1329 [inline] text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1529 text_poke_flush arch/x86/kernel/alternative.c:1720 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1727 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x12e/0x250 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate+0xbf/0x480 mm/kfence/core.c:804 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306