rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-....: (2 ticks this GP) idle=02e4/1/0x4000000000000000 softirq=16308/16308 fqs=6
rcu: hardirqs softirqs csw/system
rcu: number: 5 2 0
rcu: cputime: 0 0 6 ==> 49900(ms)
rcu: (detected by 0, t=10502 jiffies, g=14973, q=1365 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 43 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_power_efficient gc_worker
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4868 [inline]
RIP: 0010:__lock_acquire+0x43c/0x2cf0 kernel/locking/lockdep.c:5187
Code: 84 d6 01 00 00 41 8b 45 20 66 85 c0 0f 88 c9 01 00 00 4c 89 ed 0f b6 89 c5 00 00 00 84 c9 0f b6 d3 0f b6 c9 0f 44 ca 89 0c 24 <45> 8b a6 88 0b 00 00 41 8d 4c 24 ff 83 f9 ff 41 bd ff ff ff ff 44
RSP: 0018:ffffc90000a08b18 EFLAGS: 00000046
RAX: 00000000000c48fb RBX: 0000000000000003 RCX: 0000000000000003
RDX: 0000000000000003 RSI: 0000000000004000 RDI: 0000000000000000
RBP: ffff8880216a4988 R08: ffffffff89b85484 R09: ffff88802a1152c0
R10: dffffc0000000000 R11: ffffffff89b853d0 R12: 00000000000008fb
R13: ffff8880216a4988 R14: ffff8880216a3d80 R15: ffff8880216a4910
FS: 0000000000000000(0000) GS:ffff88812538f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ab2b3bc448 CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158
spin_lock include/linux/spinlock.h:342 [inline]
advance_sched+0xb4/0xc20 net/sched/sch_taprio.c:930
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:seqcount_lockdep_reader_access+0xed/0x100 include/linux/seqlock.h:76
Code: 00 75 11 e8 d5 cd fa f7 4d 85 f6 75 16 e8 cb cd fa f7 eb 15 e8 c4 cd fa f7 e8 6f b3 dd 01 4d 85 f6 74 ea e8 b5 cd fa f7 fb 5b <41> 5e c3 cc cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90
RSP: 0018:ffffc90000b37970 EFLAGS: 00000293
RAX: ffffffff89caf1bb RBX: 0000000000000001 RCX: ffff8880216a3d80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000b37ad0 R08: ffffffff9030aff7 R09: 1ffffffff20615fe
R10: dffffc0000000000 R11: fffffbfff20615ff R12: dffffc0000000000
R13: ffffffff9a9508c0 R14: 0000000000000200 R15: 000000000002aaa5
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:343 [inline]
gc_worker+0x304/0x1290 net/netfilter/nf_conntrack_core.c:1545
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
kthread+0x388/0x470 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 starved for 4975 jiffies! g14973 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:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 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: 0 UID: 0 PID: 3286 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfcf/0x13d0 kernel/smp.c:892
Code: 79 45 8b 2e 44 89 ee 83 e6 01 31 ff e8 da 07 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 85 03 0c 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 6a 03 0c
RSP: 0018:ffffc9000db67700 EFLAGS: 00000293
RAX: ffffffff81b9bc06 RBX: ffff8880b863c148 RCX: ffff8880333a9ec0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000db67840 R08: ffffffff9030aff7 R09: 1ffffffff20615fe
R10: dffffc0000000000 R11: fffffbfff20615ff R12: 1ffff110170e8169
R13: dffffc0000000000 R14: ffff8880b8740b48 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff88812528f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055fe204e4f58 CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 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+0x5f5/0x1160 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:906
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
kthread+0x388/0x470 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