rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (41 ticks this GP) idle=a9f/1/0x4000000000000002 softirq=20315/20315 fqs=20 (detected by 1, t=10502 jiffies, g=28273, q=159) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8662 Comm: syz.2.1404 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205 Code: 84 00 00 00 00 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 30 c0 10 0c 48 89 de 5b e9 57 50 44 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d c4 26 89 7e 65 8b 15 c5 26 89 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc90000007108 EFLAGS: 00000083 RAX: ffffffff81861645 RBX: 0000000000000000 RCX: ffff88802a965940 RDX: 0000000000000100 RSI: ffffffff8a7a09a0 RDI: ffff88802a965940 RBP: 0000000000000000 R08: dffffc0000000000 R09: 1ffffffff203b018 R10: dffffc0000000000 R11: fffffbfff203b019 R12: dffffc0000000000 R13: 00000000000009fc R14: 0000000000000000 R15: ffffffffa002c000 FS: 00007fc1b2d0d6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000100000000 CR3: 000000005eaf3000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_lock_release+0x5/0x20 include/linux/rcupdate.h:317 rcu_read_unlock include/linux/rcupdate.h:773 [inline] is_bpf_text_address+0x254/0x270 kernel/bpf/core.c:727 kernel_text_address kernel/extable.c:151 [inline] __kernel_text_address+0x9a/0x100 kernel/extable.c:105 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323 perf_callchain_kernel+0x34c/0x720 arch/x86/events/core.c:2784 get_perf_callchain+0x356/0x460 kernel/events/callchain.c:200 perf_callchain kernel/events/core.c:7606 [inline] perf_prepare_sample+0x352/0x1cd0 kernel/events/core.c:7633 __perf_event_output kernel/events/core.c:7802 [inline] perf_event_output_forward+0x185/0x2e0 kernel/events/core.c:7822 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515 perf_tp_event+0x383/0xbf0 kernel/events/core.c:10047 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021 perf_trace_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674 Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 f2 cc 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08 RSP: 0018:ffffc90000007b00 EFLAGS: 00000206 RAX: f4b406898e7e7f00 RBX: 1ffff92000000f64 RCX: f4b406898e7e7f00 RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: ffffffff8a7a09c0 RBP: ffffc90000007bd8 R08: ffffffff901d81af R09: 1ffffffff203b035 R10: dffffc0000000000 R11: fffffbfff203b036 R12: ffffffff8c323800 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] ieee80211_iterate_active_interfaces_atomic+0x132/0x140 net/mac80211/util.c:831 mac80211_hwsim_beacon+0x9b/0x180 drivers/net/wireless/mac80211_hwsim.c:1865 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4f2/0xb70 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1766 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:list_empty include/linux/list.h:290 [inline] RIP: 0010:plist_head_empty include/linux/plist.h:212 [inline] RIP: 0010:plist_check_head lib/plist.c:58 [inline] RIP: 0010:plist_add+0x3d/0x480 lib/plist.c:78 Code: ff 49 bd 00 00 00 00 00 fc ff df e8 ad 32 73 fd 48 89 dd 48 c1 ed 03 42 80 7c 2d 00 00 74 08 48 89 df e8 f6 4b b8 fd 4c 8b 33 <49> 39 de 74 13 e8 89 32 73 fd 49 83 c6 f0 4c 89 f7 e8 5d 0b 00 00 RSP: 0018:ffffc900039df9d0 EFLAGS: 00000246 RAX: ffffffff84061643 RBX: ffffc90000e06648 RCX: 0000000000080000 RDX: ffffc9000c1d1000 RSI: 0000000000006ed6 RDI: 0000000000006ed7 RBP: 1ffff920001c0cc9 R08: ffff88802a96595b R09: 1ffff1100552cb2b R10: dffffc0000000000 R11: ffffed100552cb2c R12: ffff88802a965940 R13: dffffc0000000000 R14: ffffc90000e06648 R15: ffffc900039dfb90 __queue_me kernel/futex/core.c:2500 [inline] queue_me kernel/futex/core.c:2519 [inline] futex_wait_queue_me+0x14a/0x440 kernel/futex/core.c:2846 futex_wait+0x256/0x680 kernel/futex/core.c:2964 do_futex+0xdb2/0x12b0 kernel/futex/core.c:3983 __do_sys_futex kernel/futex/core.c:4060 [inline] __se_sys_futex+0x389/0x420 kernel/futex/core.c:4041 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fc1b4ab3e59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc1b2d0d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007fc1b4d2cfa8 RCX: 00007fc1b4ab3e59 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc1b4d2cfa8 RBP: 00007fc1b4d2cfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc1b4d2d038 R14: 00007fffd18c7ab0 R15: 00007fffd18c7b98 rcu: rcu_preempt kthread timer wakeup didn't happen for 10460 jiffies! g28273 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=19588 rcu: rcu_preempt kthread starved for 10461 jiffies! g28273 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:27888 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x9b/0x370 kernel/rcu/tree.c:2145 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 8661 Comm: syz.2.1404 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x1110/0x1270 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x843/0x1120 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:2021 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4b4/0xb70 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] RIP: 0010:kvm_wait+0x159/0x1b0 arch/x86/kernel/kvm.c:918 Code: 89 df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 4b 0f b6 1f e8 f7 bb 4a 00 44 38 e3 75 10 66 90 0f 00 2d b9 cc f3 08 fb f4 16 ff ff ff fb e9 10 ff ff ff e8 a7 c0 88 08 89 f9 80 e1 07 38 RSP: 0018:ffffc9000322f8e0 EFLAGS: 00000246 RAX: 7f8c6d00f3ec2800 RBX: 0000000000000003 RCX: 7f8c6d00f3ec2800 RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: ffffffff8a7a09c0 RBP: ffffc9000322f990 R08: ffffffff901d81af R09: 1ffffffff203b035 R10: dffffc0000000000 R11: fffffbfff203b036 R12: 0000000000000003 R13: ffff8880b913b154 R14: dffffc0000000000 R15: 1ffff92000645f1c pv_wait arch/x86/include/asm/paravirt.h:597 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x60f/0x9c0 kernel/locking/qspinlock.c:508 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline] queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x265/0x2f0 kernel/locking/spinlock_debug.c:115 spin_lock include/linux/spinlock.h:364 [inline] futex_wake+0x219/0x540 kernel/futex/core.c:1682 do_futex+0xd73/0x12b0 kernel/futex/core.c:3988 __do_sys_futex kernel/futex/core.c:4060 [inline] __se_sys_futex+0x389/0x420 kernel/futex/core.c:4041 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fc1b4ab3e59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffd18c7cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc1b4ab3e59 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fc1b4d2cfa8 RBP: 0000000000000080 R08: 0000000000000050 R09: 0000000000000000 R10: 00007fc1b4d2cfa0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc1b4d2cfac R14: 00007fc1b4d2cfa8 R15: 00007fc1b4d2cfa0