rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=d6e4/1/0x4000000000000004 softirq=18437/18439 fqs=4 rcu: (t=10501 jiffies g=20033 q=207 ncpus=2) rcu: rcu_preempt kthread starved for 10494 jiffies! g20033 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28320 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0xee1/0x59f0 kernel/sched/core.c:6710 schedule+0xe7/0x1b0 kernel/sched/core.c:6786 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1609 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1808 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 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: 5543 Comm: kworker/u4:7 Not tainted 6.5.0-rc6-syzkaller-00270-gb320441c04c9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:296 [inline] RIP: 0010:smp_call_function_many_cond+0x4d6/0x1570 kernel/smp.c:835 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 1c 5f 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:ffffc900064f7938 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9844fe0 RCX: 0000000000000000 RDX: ffff88807e673b80 RSI: ffffffff817aa984 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10173089fd R13: 0000000000000001 R14: ffff8880b993d580 R15: ffff8880b9844fe8 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020331030 CR3: 000000000c776000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1003 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1997 [inline] text_poke_bp_batch+0x250/0x780 arch/x86/kernel/alternative.c:2207 text_poke_flush arch/x86/kernel/alternative.c:2398 [inline] text_poke_flush arch/x86/kernel/alternative.c:2395 [inline] text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:2405 arch_jump_label_transform_apply+0x17/0x30 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:831 [inline] toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:823 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.5.0-rc6-syzkaller-00270-gb320441c04c9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x31/0x70 kernel/kcov.c:207 Code: dd b0 7d 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 80 b9 03 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82 04 16 00 00 <85> c0 74 2b 8b 82 e0 15 00 00 83 f8 02 75 20 48 8b 8a e8 15 00 00 RSP: 0018:ffffc90000007bb8 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 0000000000abcc77 RCX: 0000000000000100 RDX: ffffffff8c6957c0 RSI: ffffffff88585296 RDI: 0000000000000005 RBP: 00000010c6f7a0b5 R08: 0000000000000005 R09: 00000000000f4240 R10: 00000000000f4240 R11: 0000000000000000 R12: 00000000000f4240 R13: 0000000000000001 R14: 0000000000112e0b R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f99c1365d58 CR3: 000000002c8d3000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pie_calculate_probability+0x266/0x850 net/sched/sch_pie.c:347 fq_pie_timer+0x1da/0x4f0 net/sched/sch_fq_pie.c:387 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x764/0xb10 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x218/0x965 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:tick_nohz_idle_enter+0x13b/0x1d0 kernel/time/tick-sched.c:1175 Code: 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 04 02 84 c0 74 02 7e 55 80 0b 01 48 89 df e8 8c e4 ff ff e8 87 7a 13 00 fb 5b <5d> c3 e8 be cf 0c 00 65 8b 1d b3 4d 89 7e 31 ff 89 de e8 1e cb 0c RSP: 0018:ffffffff8c607e20 EFLAGS: 00000206 RAX: 00000000003c7d0f RBX: 0000000000000000 RCX: 1ffffffff1d56e41 RDX: 0000000000000000 RSI: ffffffff8a6c80a0 RDI: ffffffff8ac81200 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8eaba397 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 do_idle+0x82/0x3f0 kernel/sched/idle.c:256 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379 rest_init+0x16f/0x2b0 init/main.c:726 arch_call_rest_init+0x13/0x30 init/main.c:823 start_kernel+0x39f/0x480 init/main.c:1068 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:556 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:537 secondary_startup_64_no_verify+0x167/0x16b