rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4617/1:b..l
(detected by 0, t=10502 jiffies, g=10033, q=418)
task:syz.0.86 state:R running task stack:27648 pid: 4617 ppid: 4191 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
irqentry_exit+0x63/0x70 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:35 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline]
RIP: 0010:lock_is_held_type+0x64/0x190 kernel/locking/lockdep.c:5662
Code: 00 00 00 65 48 8b 1d 3b ff 58 76 83 bb ec 0a 00 00 00 0f 85 df 00 00 00 41 89 f7 49 89 fe 48 c7 04 24 00 00 00 00 9c 8f 04 24 <4c> 8b 2c 24 fa 48 c7 c7 60 2a 0b 8a e8 4b 0e 00 00 65 ff 05 84 08
RSP: 0018:ffffc9000150fe98 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888023870000 RCX: 400983fffd18dc00
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8c11c760
RBP: 00000000ffffffff R08: dffffc0000000000 R09: fffffbfff1ff7c19
R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: dffffc0000000000
R13: ffff88806233cdc0 R14: ffffffff8c11c760 R15: 00000000ffffffff
__task_pid_nr_ns+0x1c4/0x420 kernel/pid.c:500
task_tgid_vnr include/linux/sched.h:1585 [inline]
__ia32_sys_getpid+0x19/0x20 kernel/sys.c:945
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: 0033:0x7fc24a10c567
RSP: 002b:00007ffc6dd6e488 EFLAGS: 00000206 ORIG_RAX: 0000000000000027
RAX: ffffffffffffffda RBX: 00007ffc6dd6e5f0 RCX: 00007fc24a10c567
RDX: 00007ffc6dd6e4c0 RSI: 00007ffc6dd6e5f0 RDI: 0000000000000021
RBP: 0000000000000000 R08: 00007fc24a356000 R09: 00007fc24a358000
R10: 00000000816803eb R11: 0000000000000206 R12: 000000000000000a
R13: 0000000000000000 R14: ffffffff8168004c R15: 000000000001ff53
rcu: rcu_preempt kthread starved for 9246 jiffies! g10033 f0x0 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:26688 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:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 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+0x10c8/0x1220 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+0x831/0x1110 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:1818
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+0x4fe/0xc40 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:default_idle+0xb/0x10 arch/x86/kernel/process.c:730
Code: bf 48 89 df e8 66 76 09 f8 eb b5 e8 9f af f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 37 06 53 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffffff8be07dc8 EFLAGS: 000002c6
RAX: 766c151bdd694000 RBX: ffffffff8bebc480 RCX: 766c151bdd694000
RDX: 0000000000000001 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580
RBP: ffffffff8be07ef8 R08: dffffc0000000000 R09: ffffed1017207662
R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8d699d28
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff17d7890
default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
cpuidle_idle_call kernel/sched/idle.c:194 [inline]
do_idle+0x21b/0x5b0 kernel/sched/idle.c:306
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
start_kernel+0x486/0x530 init/main.c:1154
secondary_startup_64_no_verify+0xb1/0xbb