rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: (detected by 1, t=10502 jiffies, g=14465, q=1236 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294959340-4294948838), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g14465 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27560 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5351 [inline]
__schedule+0x1737/0x4d30 kernel/sched/core.c:6954
__schedule_loop kernel/sched/core.c:7036 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7051
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 1331 Comm: kworker/u8:6 Not tainted 6.16.0-syzkaller-06619-gd942fe13f72b #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:queued_write_lock_slowpath+0x120/0x260 kernel/locking/qrwlock.c:85
Code: b0 f6 f0 81 0b 00 01 00 00 43 0f b6 04 27 84 c0 74 35 89 d9 80 e1 07 80 c1 03 38 c1 7c 29 48 89 df e8 24 4a b0 f6 eb 1f f3 90 <43> 0f b6 04 27 84 c0 74 14 89 d9 80 e1 07 80 c1 03 38 c1 7c 08 48
RSP: 0018:ffffc90000a08500 EFLAGS: 00000206
RAX: 00000000000001ff RBX: ffffffff8f6186c0 RCX: ffffffff8b728928
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8f6186c0
RBP: ffffc90000a085b0 R08: ffffffff8f6186c3 R09: 1ffffffff1ec30d8
R10: dffffc0000000000 R11: fffffbfff1ec30d9 R12: dffffc0000000000
R13: 1ffff920001410a4 R14: ffffc90000a08550 R15: 1ffffffff1ec30d8
FS: 0000000000000000(0000) GS:ffff888125d80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564d81b3b290 CR3: 000000000df38000 CR4: 00000000003526f0
Call Trace:
queued_write_lock include/asm-generic/qrwlock.h:101 [inline]
do_raw_write_lock+0x1f2/0x260 kernel/locking/spinlock_debug.c:211
___neigh_create+0xe81/0x2260 net/core/neighbour.c:690
ip6_finish_output2+0xb4d/0x16a0 net/ipv6/ip6_output.c:132
NF_HOOK include/linux/netfilter.h:318 [inline]
ndisc_send_skb+0xb54/0x1440 net/ipv6/ndisc.c:512
addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4037
call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
expire_timers kernel/time/timer.c:1798 [inline]
__run_timers kernel/time/timer.c:2372 [inline]
__run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
run_timer_base kernel/time/timer.c:2393 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217
Code: 08 00 9a 92 65 8b 15 68 4f da 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00 00 74 2c 8b 91 18 16 00 00 <83> fa 02 75 21 48 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c
RSP: 0018:ffffc9000401f658 EFLAGS: 00000246
RAX: ffffffff81b4451b RBX: 1ffff110170c8385 RCX: ffff888027691e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000401f7e0 R08: ffffffff8fa07bf7 R09: 1ffffffff1f40f7e
R10: dffffc0000000000 R11: fffffbfff1f40f7f R12: ffff8880b8641c28
R13: dffffc0000000000 R14: ffff8880b873b180 R15: 0000000000000000
csd_lock_wait kernel/smp.c:342 [inline]
smp_call_function_many_cond+0xd4b/0x12d0 kernel/smp.c:877
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2691 [inline]
smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2901
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
sched: DL replenish lagged too much