rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16
rcu: (detected by 0, t=10504 jiffies, g=58065, q=543 ncpus=2)
task:ktimers/0 state:R running task stack:23624 pid:16 tgid:16 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:lock_release+0x2e1/0x3c0 kernel/locking/lockdep.c:5968
Code: d7 03 11 00 00 00 00 eb b5 e8 bb 46 b6 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 33 91 03 11 48 3b 44 24 28 75 48 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 10 1b ba 09 cc 48 8d 3d 28 08 13
RSP: 0018:ffffc90000157a80 EFLAGS: 00000282
RAX: e805da5ae6fbde00 RBX: 0000000000000206 RCX: 0000000000000046
RDX: 00000000d8b0714a RSI: ffffffff8dae07db RDI: ffffffff8bcc4b80
RBP: ffff88801ce80cb8 R08: ffffffff8b5ad242 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000005
R13: 0000000000000005 R14: ffff888060886400 R15: ffff88801ce80000
rt_spin_unlock+0x29/0x200 kernel/locking/spinlock_rt.c:80
spin_unlock include/linux/spinlock_rt.h:115 [inline]
advance_sched+0x9a3/0xc90 net/sched/sch_taprio.c:989
__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 10534 jiffies! g58065 f0x0 RCU_GP_WAIT_FQS(5) ->state=I
rcu: Possible timer handling issue on cpu=1 timer-softirq=45770
rcu: rcu_preempt kthread starved for 10537 jiffies! g58065 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
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:in_softirq_really kernel/kcov.c:167 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:179 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x2f/0x80 kernel/kcov.c:213
Code: 8b 04 24 65 48 8b 0d e8 fb de 10 65 48 8b 15 e8 fb de 10 89 d7 81 e7 00 00 00 ff be 00 01 00 00 23 b1 fc 0b 00 00 09 f7 74 1d <85> f6 74 45 81 fa ff ff ff 0f 77 3d 81 e2 00 00 00 0f 75 35 83 b9
RSP: 0018:ffffc90000a3fae8 EFLAGS: 00000206
RAX: ffffffff89638440 RBX: 0000000000000000 RCX: ffff88801d68be80
RDX: 8000000000000000 RSI: 0000000000000100 RDI: 0000000000000100
RBP: 0000000000000000 R08: 0000000000000100 R09: 0000000000000100
R10: dffffc0000000000 R11: fffffbfff1f64570 R12: ffff88805f435110
R13: 0000000000000002 R14: 18d99f0424a59600 R15: ffff88805f435110
FS: 0000000000000000(0000) GS:ffff888125cc4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5a66e30218 CR3: 0000000034d6c000 CR4: 00000000003526f0
Call Trace:
should_restart_cycle net/sched/sch_taprio.c:876 [inline]
advance_sched+0x3b0/0xc90 net/sched/sch_taprio.c:955
__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