rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=27017, q=492 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294966515-4294956013), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g27017 f0x2 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:27056 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x1796/0x49d0 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1246 Comm: aoe_tx0 Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:check_preemption_disabled+0x4/0x120 lib/smp_processor_id.c:13 Code: 8c 48 c7 c6 60 1e 1f 8c eb 1c 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 <41> 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 RSP: 0018:ffffc90000007828 EFLAGS: 00000083 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81725464 RDX: 0000000000000000 RSI: ffffffff8c1f1e60 RDI: ffffffff8c1f1e20 RBP: ffffc900000079b8 R08: ffffffff8fac17ef R09: 1ffffffff1f582fd R10: dffffc0000000000 R11: fffffbfff1f582fe R12: 1ffff92000000f14 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b943f2d8 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f43a000 CR3: 000000005c3ce000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:724 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xe3/0x550 kernel/locking/lockdep.c:5725 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 do_start_rt_bandwidth kernel/sched/rt.c:107 [inline] start_rt_bandwidth kernel/sched/rt.c:130 [inline] inc_rt_group kernel/sched/rt.c:1187 [inline] inc_rt_tasks kernel/sched/rt.c:1230 [inline] __enqueue_rt_entity kernel/sched/rt.c:1405 [inline] enqueue_rt_entity kernel/sched/rt.c:1454 [inline] enqueue_task_rt+0x5d3/0xcf0 kernel/sched/rt.c:1489 enqueue_task+0x1a1/0x2f0 kernel/sched/core.c:2116 activate_task kernel/sched/core.c:2146 [inline] ttwu_do_activate+0x1d1/0x7e0 kernel/sched/core.c:3793 ttwu_queue kernel/sched/core.c:4057 [inline] try_to_wake_up+0x884/0x1470 kernel/sched/core.c:4378 signal_wake_up_state+0xb4/0x120 kernel/signal.c:773 signal_wake_up include/linux/sched/signal.h:448 [inline] complete_signal+0x94a/0xcf0 kernel/signal.c:1065 __send_signal_locked+0xb1b/0xdc0 kernel/signal.c:1185 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 kernel/signal.c:1451 do_bpf_send_signal+0x85/0x190 kernel/trace/bpf_trace.c:838 irq_work_single+0xe2/0x240 kernel/irq_work.c:221 irq_work_run_list kernel/irq_work.c:252 [inline] irq_work_run+0x18b/0x350 kernel/irq_work.c:261 __sysvec_irq_work+0xb8/0x430 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5282 Code: c9 50 e8 99 c9 0b 00 48 83 c4 08 4c 89 f7 e8 cd 38 00 00 0f 1f 44 00 00 4c 89 f7 e8 e0 c2 21 0a e8 6b f8 36 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0018:ffffc90004dc7988 EFLAGS: 00000282 RAX: 490214f75cc71600 RBX: ffff8880232b0000 RCX: ffffffff94769603 RDX: dffffc0000000000 RSI: ffffffff8bcaba80 RDI: ffffffff8c1f1e80 RBP: ffffc90004dc79d0 R08: ffffffff8fac17ef R09: 1ffffffff1f582fd R10: dffffc0000000000 R11: fffffbfff1f582fe R12: 1ffff11017287e9f R13: dffffc0000000000 R14: ffff8880b943e780 R15: ffff8880b943f4f8 context_switch kernel/sched/core.c:5411 [inline] __schedule+0x179e/0x49d0 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__schedule_loop kernel/sched/core.c:6824 [inline] RIP: 0010:schedule+0x138/0x320 kernel/sched/core.c:6837 Code: be 01 00 00 00 e8 28 3f 00 f9 48 c7 c7 20 10 1f 8e 4c 89 f6 e8 59 c5 eb f5 48 89 eb 48 c1 eb 03 eb 0a 48 f7 45 00 08 00 00 00 <74> 2c bf 01 00 00 00 e8 5c d3 de f5 31 ff e8 d5 b4 ff ff bf 01 00 RSP: 0018:ffffc90004dc7d68 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 1ffff11004656000 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8bcaba80 RDI: 0000000000000001 RBP: ffff8880232b0000 R08: ffffffff8fac17ef R09: 1ffffffff1f582fd R10: dffffc0000000000 R11: fffffbfff1f582fe R12: dffffc0000000000 R13: ffff8880232b1768 R14: ffffffff8b86b430 R15: ffff8880232b1278 kthread+0x33f/0x450 drivers/block/aoe/aoecmd.c:1236 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244