rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=509/1/0x4000000000000000 softirq=77647/77647 fqs=0 (detected by 1, t=10502 jiffies, g=113953, q=1085) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 26680 Comm: syz.7.6597 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:memset+0x22/0x40 mm/kasan/shadow.c:47 Code: 00 00 00 e9 30 ef ff ff 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 12 ef ff ff 84 c0 74 11 <4c> 89 f7 89 ee 48 89 da 5b 41 5e 5d e9 8d d5 44 02 31 c0 5b 41 5e RSP: 0018:ffffc900000075e0 EFLAGS: 00000002 RAX: ffffffff8196e001 RBX: 0000000000000100 RCX: ffffffff8196e104 RDX: 0000000000000001 RSI: 0000000000000100 RDI: ffffc90000007680 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff52000000ef0 R10: 0000000000000000 R11: 0000000000000020 R12: ffffe8ffffc361a8 R13: ffffe8fffee22000 R14: ffffc90000007680 R15: 0000000000000014 FS: 00007f30893b46c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000000016e0 CR3: 000000007903b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: perf_tp_event+0xb4/0xb50 kernel/events/core.c:10030 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021 perf_trace_preemptirq_template+0x2be/0x380 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+0x84/0x480 kernel/rcu/tree_plugin.h:674 Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 dd 13 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90000007ae0 EFLAGS: 00000206 RAX: 8c18018f49461900 RBX: 1ffff92000000f60 RCX: 8c18018f49461900 RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: ffffffff8a59a240 RBP: ffffc90000007bb8 R08: dffffc0000000000 R09: ffffed101720765a R10: ffffed101720765a R11: 1ffff11017207659 R12: ffffffff8c120900 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:771 [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:1690 [inline] __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1754 hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1771 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 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:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804 Code: be ff ff ff ff e8 ec 7c 55 08 85 c0 74 4a 4d 85 ff 75 66 0f 1f 44 00 00 48 89 df e8 46 e7 5e 08 e8 71 75 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 d9 0f fe ff 43 80 3c RSP: 0018:ffffc9000317f6e8 EFLAGS: 00000286 RAX: 8c18018f49461900 RBX: ffff8880b903a300 RCX: 8c18018f49461900 RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: ffffffff8a59a240 RBP: 1ffff1101720760b R08: dffffc0000000000 R09: ffffed101720765a R10: ffffed101720765a R11: 1ffff11017207659 R12: 1ffff110172075b9 R13: dffffc0000000000 R14: ffff8880b903adc8 R15: 0000000000000000 finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921 context_switch kernel/sched/core.c:5052 [inline] __schedule+0x11c3/0x4390 kernel/sched/core.c:6395 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6596 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:403 [inline] queue_me kernel/futex/core.c:2520 [inline] futex_wait_queue_me+0x178/0x440 kernel/futex/core.c:2846 futex_wait+0x202/0x5c0 kernel/futex/core.c:2964 do_futex+0xd1c/0x1240 kernel/futex/core.c:3982 __do_sys_futex kernel/futex/core.c:4059 [inline] __se_sys_futex+0x3a3/0x430 kernel/futex/core.c:4040 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: 0033:0x7f308b14cbe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f30893b40e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f308b383fa8 RCX: 00007f308b14cbe9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f308b383fa8 RBP: 00007f308b383fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f308b384038 R14: 00007ffdfb049f30 R15: 00007ffdfb04a018 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g113953 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=65147 rcu: rcu_preempt kthread starved for 10502 jiffies! g113953 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27008 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 26680 Comm: syz.7.6597 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:irq_work_single kernel/irq_work.c:154 [inline] RIP: 0010:irq_work_run_list+0x14c/0x330 kernel/irq_work.c:177 Code: 48 89 df be 04 00 00 00 e8 b1 99 38 00 43 0f b6 04 2c 84 c0 0f 85 27 01 00 00 45 89 fd 41 83 e5 fe 44 89 2b f0 83 44 24 fc 00 <44> 89 fe 83 e6 08 31 ff e8 17 35 f4 ff 44 89 f8 83 e0 08 75 7e e8 RSP: 0018:ffffc90000007920 EFLAGS: 00000086 RAX: 0000000000000000 RBX: ffff8880b903b1b8 RCX: ffffffff818398cf RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff8880b903b1b8 RBP: ffffc900000079d8 R08: dffffc0000000000 R09: ffffed1017207638 R10: ffffed1017207638 R11: 1ffff11017207637 R12: 1ffff11017207637 R13: 0000000000000022 R14: ffff8880b903b1b0 R15: 0000000000000023 FS: 00007f30893b46c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000000016e0 CR3: 000000007903b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: irq_work_run+0x63/0xe0 kernel/irq_work.c:186 __sysvec_irq_work+0x98/0x240 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x4a/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674 Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 dd 13 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90000007ae0 EFLAGS: 00000206 RAX: 8c18018f49461900 RBX: 1ffff92000000f60 RCX: 8c18018f49461900 RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: ffffffff8a59a240 RBP: ffffc90000007bb8 R08: dffffc0000000000 R09: ffffed101720765a R10: ffffed101720765a R11: 1ffff11017207659 R12: ffffffff8c120900 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:771 [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:1690 [inline] __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1754 hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1771 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 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:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804 Code: be ff ff ff ff e8 ec 7c 55 08 85 c0 74 4a 4d 85 ff 75 66 0f 1f 44 00 00 48 89 df e8 46 e7 5e 08 e8 71 75 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 d9 0f fe ff 43 80 3c RSP: 0018:ffffc9000317f6e8 EFLAGS: 00000286 RAX: 8c18018f49461900 RBX: ffff8880b903a300 RCX: 8c18018f49461900 RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: ffffffff8a59a240 RBP: 1ffff1101720760b R08: dffffc0000000000 R09: ffffed101720765a R10: ffffed101720765a R11: 1ffff11017207659 R12: 1ffff110172075b9 R13: dffffc0000000000 R14: ffff8880b903adc8 R15: 0000000000000000 finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921 context_switch kernel/sched/core.c:5052 [inline] __schedule+0x11c3/0x4390 kernel/sched/core.c:6395 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6596 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:403 [inline] queue_me kernel/futex/core.c:2520 [inline] futex_wait_queue_me+0x178/0x440 kernel/futex/core.c:2846 futex_wait+0x202/0x5c0 kernel/futex/core.c:2964 do_futex+0xd1c/0x1240 kernel/futex/core.c:3982 __do_sys_futex kernel/futex/core.c:4059 [inline] __se_sys_futex+0x3a3/0x430 kernel/futex/core.c:4040 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: 0033:0x7f308b14cbe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f30893b40e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f308b383fa8 RCX: 00007f308b14cbe9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f308b383fa8 RBP: 00007f308b383fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f308b384038 R14: 00007ffdfb049f30 R15: 00007ffdfb04a018