rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (0 ticks this GP) idle=d8fc/1/0x4000000000000000 softirq=34424/34424 fqs=0
rcu: (detected by 0, t=10506 jiffies, g=31825, q=292 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8620 Comm: syz.0.813 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:qdisc_dev include/net/sch_generic.h:612 [inline]
RIP: 0010:taprio_set_budgets+0x63/0x310 net/sched/sch_taprio.c:666
Code: 02 00 0f 85 bf 02 00 00 48 8b 44 24 18 48 8b 68 08 48 b8 00 00 00 00 00 fc ff df 48 8d 7d 40 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 8d 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6d 40 48 89
RSP: 0018:ffffc90000a08d78 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8880302f7280 RCX: 1ffff1100a8f06a6
RDX: 1ffff1100605ee08 RSI: ffffffff89a8b182 RDI: ffff8880302f7040
RBP: ffff8880302f7000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: ffffc90000a08ff8 R12: 0000000000000000
R13: ffff8880547aac00 R14: ffff8880547aac00 R15: ffff8880547aac00
FS: 00007ff02b8936c0(0000) GS:ffff8881243ef000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff02b871ff8 CR3: 00000000748df000 CR4: 00000000003526f0
Call Trace:
advance_sched+0x66e/0xd20 net/sched/sch_taprio.c:984
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x9e/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:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 56 4d 47 f6 48 89 df e8 de 9c 47 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 a5 ae 36 f6 65 8b 05 ae 48 75 08 85 c0 74 16 5b
RSP: 0018:ffffc9000f037d78 EFLAGS: 00000246
RAX: 0000000000000046 RBX: ffffffff9b22b3d8 RCX: ffffffff8211cc5f
RDX: 0000000000000000 RSI: ffffffff8c1e6000 RDI: ffffffff8b9dc792
RBP: 0000000000000287 R08: 0000000000000000 R09: fffffbfff21b6932
R10: 0000000000000000 R11: ffffffffffffffff R12: 1ffff92001e06fb6
R13: 000000000cfaedc6 R14: 000000000cfaedc6 R15: 0000000000000000
class_raw_spinlock_irqsave_destructor include/linux/spinlock.h:571 [inline]
do_settimeofday64+0x326/0x4d0 kernel/time/timekeeping.c:1665
do_sys_settimeofday64+0x1dc/0x260 kernel/time/time.c:195
__do_sys_clock_settime kernel/time/posix-timers.c:1139 [inline]
__se_sys_clock_settime kernel/time/posix-timers.c:1123 [inline]
__x64_sys_clock_settime+0x1c1/0x2a0 kernel/time/posix-timers.c:1123
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff02a99ce59
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:00007ff02b893028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007ff02ac15fa0 RCX: 00007ff02a99ce59
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000000
RBP: 00007ff02aa32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff02ac16038 R14: 00007ff02ac15fa0 R15: 00007fff725869f8
rcu: rcu_preempt kthread starved for 10506 jiffies! g31825 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:29168 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7322
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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: 0 UID: 0 PID: 6512 Comm: kworker/u8:9 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x589/0x16c0 kernel/smp.c:892
Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 b9 95 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 2c 0f 00 00 8b 45 08 31
RSP: 0018:ffffc9000322f878 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81fce98d
RDX: ffff8880358a0000 RSI: ffffffff81fce967 RDI: ffff8880358a0000
RBP: ffff8880b85410c0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10170a8219 R14: 0000000000000001 R15: ffff8880b843c700
FS: 0000000000000000(0000) GS:ffff8881242ef000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff02b872d58 CR3: 000000000e592000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x337/0xc60 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
jump_label_update+0x37a/0x550 kernel/jump_label.c:910
static_key_enable_cpuslocked+0x1bc/0x270 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate mm/kfence/core.c:911 [inline]
toggle_allocation_gate+0xfe/0x2d0 mm/kfence/core.c:903
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245