rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6128/1:b..l P31/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=13381, q=495 ncpus=2)
task:khungtaskd state:R running task stack:28544 pid:31 tgid:31 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_hung_uninterruptible_tasks kernel/hung_task.c:301 [inline]
RIP: 0010:watchdog+0x2d0/0xfe0 kernel/hung_task.c:491
Code: 51 e9 8d 0f 84 f1 0b 00 00 49 6b c5 9c 48 89 44 24 68 4c 8d a9 18 04 00 00 4c 89 e8 48 c1 e8 03 48 89 44 24 70 42 80 3c 38 00 <48> 89 4c 24 20 74 0d 4c 89 ef e8 31 43 63 00 48 8b 4c 24 20 49 8b
RSP: 0018:ffffc90000a77cf0 EFLAGS: 00000246
RAX: 1ffff11004a0d124 RBX: ffff888025068508 RCX: ffff888025068508
RDX: 0000000000000000 RSI: 0000000000000402 RDI: 0000000000000002
RBP: 1ffffffff1bc2240 R08: 0000000000000000 R09: ffffffff81bfd21e
R10: dffffc0000000000 R11: fffffbfff254ce01 R12: 00000000003ffed5
R13: ffff888025068920 R14: 00000000ffffcdd9 R15: dffffc0000000000
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:syz.1.22 state:R running task stack:25632 pid:6128 tgid:6128 ppid:5980 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7238
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x4b/0x3e0 kernel/locking/lockdep.c:5879
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
is_bpf_text_address+0x28d/0x2b0 kernel/bpf/core.c:778
kernel_text_address+0xa5/0xe0 kernel/extable.c:125
__kernel_text_address+0xd/0x40 kernel/extable.c:79
unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
__free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
__slab_free+0x303/0x3c0 mm/slub.c:4591
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:340
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4180 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
__kmalloc_cache_noprof+0x1be/0x3d0 mm/slub.c:4391
kmalloc_noprof include/linux/slab.h:905 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
bpf_raw_tp_link_attach+0x24e/0x6c0 kernel/bpf/syscall.c:4135
bpf_raw_tracepoint_open+0x1b2/0x220 kernel/bpf/syscall.c:4183
__sys_bpf+0x75a/0x870 kernel/bpf/syscall.c:6071
__do_sys_bpf kernel/bpf/syscall.c:6139 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6137 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdad918ebe9
RSP: 002b:00007fff342782f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fdad93b5fa0 RCX: 00007fdad918ebe9
RDX: 0000000000000010 RSI: 0000200000000540 RDI: 0000000000000011
RBP: 00007fdad9211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdad93b5fa0 R14: 00007fdad93b5fa0 R15: 0000000000000003
rcu: rcu_preempt kthread starved for 6412 jiffies! g13381 f0x0 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:27848 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x70e/0x8a0 kernel/kthread.c:463
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: 981 Comm: kworker/1:2 Not tainted 6.16.0-syzkaller-12063-g37816488247d #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_power_efficient wg_ratelimiter_gc_entries
RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5225
Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 cf 37 ea 09 e8 5a 3f 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc9000390f698 EFLAGS: 00000282
RAX: 0efb6c723e1aa300 RBX: 0000000000000000 RCX: 0efb6c723e1aa300
RDX: 0000000000000006 RSI: ffffffff8d9b4943 RDI: ffffffff8be32680
RBP: ffffc9000390f6f0 R08: ffffffff8fa34737 R09: 1ffffffff1f468e6
R10: dffffc0000000000 R11: fffffbfff1f468e7 R12: ffff888025905a00
R13: dffffc0000000000 R14: ffff888030031e00 R15: ffff8880b873ab58
FS: 0000000000000000(0000) GS:ffff888125d21000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000031953bc CR3: 000000007fe56000 CR4: 00000000003526f0
Call Trace:
context_switch kernel/sched/core.c:5360 [inline]
__schedule+0x17a0/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
wg_ratelimiter_gc_entries+0x384/0x450 drivers/net/wireguard/ratelimiter.c:76
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245