rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P29
rcu: (detected by 1, t=10502 jiffies, g=107553, q=8800 ncpus=2)
task:ktimers/1 state:R running task stack:22024 pid:29 tgid:29 ppid:2 task_flags:0x4208040 flags:0x00080000
Call Trace:
sched_show_task+0x4aa/0x5f0 kernel/sched/core.c:8250
rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline]
print_other_cpu_stall+0xfbf/0x1350 kernel/rcu/tree_stall.h:683
check_cpu_stall kernel/rcu/tree_stall.h:860 [inline]
rcu_pending kernel/rcu/tree.c:3744 [inline]
rcu_sched_clock_irq+0x9fe/0x10e0 kernel/rcu/tree.c:2749
update_process_times+0x234/0x2d0 kernel/time/timer.c:2475
tick_sched_handle kernel/time/tick-sched.c:296 [inline]
tick_nohz_handler+0x38f/0x6b0 kernel/time/tick-sched.c:317
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x3a0/0xaf0 kernel/time/hrtimer.c:2131
hrtimer_interrupt+0x4c2/0xa80 kernel/time/hrtimer.c:2250
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:221
Code: f7 e8 bd 0e 46 f6 f7 c3 00 02 00 00 74 05 e8 a0 6d 72 f6 9c 58 a9 00 02 00 00 75 29 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 14 15 38 f6 65 48 8b 05 ac 23 49 07 48 85 c0 74 18 5b 41 5e c3
RSP: 0018:ffffc90000a3fa08 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000246 RCX: 8000000000000002
RDX: 0000000000000002 RSI: ffffffff8d86e34a RDI: 0000000000000001
RBP: ffffc90000a3fae0 R08: ffffffff8fb22d7f R09: 1ffffffff1f645af
R10: dffffc0000000000 R11: fffffbfff1f645b0 R12: 1ffff92000147f4d
R13: 0000000000000246 R14: ffff888043e9a3a8 R15: ffffc90000a3fa60
raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:97 [inline]
rtlock_slowlock kernel/locking/rtmutex.c:1923 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x17a/0x400 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:45 [inline]
advance_sched+0xc8/0xc90 net/sched/sch_taprio.c:931
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x3eb/0xaf0 kernel/time/hrtimer.c:2131
hrtimer_run_softirq+0x1e1/0x2e0 kernel/time/hrtimer.c:2148
handle_softirqs+0x1da/0x6d0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
run_ktimerd+0x6a/0x100 kernel/softirq.c:1174
smpboot_thread_fn+0x565/0xa70 kernel/smpboot.c:160
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread timer wakeup didn't happen for 10526 jiffies! g107553 f0x0 RCU_GP_WAIT_FQS(5) ->state=I
rcu: Possible timer handling issue on cpu=1 timer-softirq=65715
rcu: rcu_preempt kthread starved for 10527 jiffies! g107553 f0x0 RCU_GP_WAIT_FQS(5) ->state=I ->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:27784 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x16d9/0x5700 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 29 Comm: ktimers/1 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:221
Code: f7 e8 bd 0e 46 f6 f7 c3 00 02 00 00 74 05 e8 a0 6d 72 f6 9c 58 a9 00 02 00 00 75 29 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 14 15 38 f6 65 48 8b 05 ac 23 49 07 48 85 c0 74 18 5b 41 5e c3
RSP: 0018:ffffc90000a3fa08 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000246 RCX: 8000000000000002
RDX: 0000000000000002 RSI: ffffffff8d86e34a RDI: 0000000000000001
RBP: ffffc90000a3fae0 R08: ffffffff8fb22d7f R09: 1ffffffff1f645af
R10: dffffc0000000000 R11: fffffbfff1f645b0 R12: 1ffff92000147f4d
R13: 0000000000000246 R14: ffff888043e9a3a8 R15: ffffc90000a3fa60
FS: 0000000000000000(0000) GS:ffff888125cc2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2de1dff8 CR3: 000000005bcba000 CR4: 00000000003526f0
Call Trace:
raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:97 [inline]
rtlock_slowlock kernel/locking/rtmutex.c:1923 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x17a/0x400 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:45 [inline]
advance_sched+0xc8/0xc90 net/sched/sch_taprio.c:931
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x3eb/0xaf0 kernel/time/hrtimer.c:2131
hrtimer_run_softirq+0x1e1/0x2e0 kernel/time/hrtimer.c:2148
handle_softirqs+0x1da/0x6d0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
run_ktimerd+0x6a/0x100 kernel/softirq.c:1174
smpboot_thread_fn+0x565/0xa70 kernel/smpboot.c:160
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245