rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (2 GPs behind) idle=6f2c/0/0x1 softirq=8691/8692 fqs=0 rcu: (detected by 0, t=10502 jiffies, g=7857, q=223 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.6.0-rc5-syzkaller-01232-g85605fb694f0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 RIP: 0010:lock_is_held_type+0x0/0x140 kernel/locking/lockdep.c:5809 Code: f9 85 c0 74 ec 8b 05 23 fe 8c 04 85 c0 75 e2 48 c7 c6 a0 ad 8c 8a 48 c7 c7 00 aa 8c 8a e8 28 7f 0c f7 0f 0b 31 c0 eb cb 66 90 0f 1e fa 41 57 41 56 41 55 41 bd ff ff ff ff 41 54 55 53 48 83 RSP: 0018:ffffc900001f0d88 EFLAGS: 00000046 RAX: 0000000000010002 RBX: 0000000000000001 RCX: 0000000000000000 RDX: ffff888016e63b80 RSI: 00000000ffffffff RDI: ffff88801fea2300 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880b992b940 R13: 0000000000000000 R14: ffff88801fea2340 R15: ffffffff88665550 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5c64ab82d0 CR3: 000000000c976000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:288 [inline] advance_sched+0x789/0xc60 net/sched/sch_taprio.c:938 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x203/0xc10 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1063 [inline] __sysvec_apic_timer_interrupt+0x105/0x3f0 arch/x86/kernel/apic/apic.c:1080 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1074 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x1b/0x20 drivers/acpi/processor_idle.c:113 Code: ed c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 65 48 8b 04 25 c0 bc 03 00 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 97 c5 b2 00 fb f4 c3 0f 1f 00 0f b6 47 08 3c 01 74 0b 3c 02 74 05 8b 7f 04 eb 9f RSP: 0018:ffffc90000187d58 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8a4182ae RDX: 0000000000000001 RSI: ffff888014eb8800 RDI: ffff888014eb8864 RBP: ffff888014eb8864 R08: 0000000000000001 R09: ffffed1017326dbd R10: ffff8880b9936deb R11: 0000000000000000 R12: ffff888141266000 R13: ffffffff8d6637e0 R14: 0000000000000001 R15: 0000000000000000 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x82/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x315/0x3f0 kernel/sched/idle.c:282 cpu_startup_entry+0x50/0x60 kernel/sched/idle.c:380 start_secondary+0x20e/0x2a0 arch/x86/kernel/smpboot.c:326 secondary_startup_64_no_verify+0x166/0x16b INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.560 msecs rcu: rcu_preempt kthread starved for 10502 jiffies! g7857 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:28656 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0xee1/0x5a10 kernel/sched/core.c:6695 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1613 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1812 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 11 Comm: kworker/u4:0 Not tainted 6.6.0-rc5-syzkaller-01232-g85605fb694f0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:300 [inline] RIP: 0010:smp_call_function_many_cond+0x4d6/0x1570 kernel/smp.c:844 Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 fc 4c 89 fd 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 7c 8b 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 3c 0e 00 00 8b 43 08 31 RSP: 0018:ffffc90000107920 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9941a60 RCX: 0000000000000000 RDX: ffff888016e4bb80 RSI: ffffffff817c4514 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed101732834d R13: 0000000000000001 R14: ffff8880b983d8c0 R15: ffff8880b9941a68 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555565e06f8 CR3: 000000000c976000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1012 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1993 [inline] text_poke_bp_batch+0x2ce/0x960 arch/x86/kernel/alternative.c:2203 text_poke_flush arch/x86/kernel/alternative.c:2394 [inline] text_poke_flush arch/x86/kernel/alternative.c:2391 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2401 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32e/0x410 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b5/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:830 [inline] toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:822 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304