rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P26505/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=113981, q=1702 ncpus=2)
task:syz-executor state:R running task stack:22760 pid:26505 tgid:26505 ppid:26495 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7552
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:228 [inline]
RIP: 0010:unwind_next_frame+0x1f6/0x2550 arch/x86/kernel/unwind_orc.c:510
Code: 08 8b 15 dd 29 b1 0c 8d 42 ff 44 39 f8 0f 86 6c 04 00 00 44 89 f8 4c 8d 2c 85 24 a2 71 91 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 <84> c0 4c 89 e3 0f 85 66 1d 00 00 45 8b 6d 00 44 89 f8 ff c0 4c 8d
RSP: 0018:ffffc90002dc7460 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000080000000
RDX: 00000000000aaba9 RSI: ffffffff8c291100 RDI: ffffffff8c2910c0
RBP: ffffffff81b105c8 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90002dc7558 R11: ffffffff81b10630 R12: dffffc0000000000
R13: ffffffff91746638 R14: ffffc90002dc7508 R15: 000000000000b105
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1397 [inline]
__free_frozen_pages+0xc0d/0xd20 mm/page_alloc.c:2938
__slab_free+0x274/0x2c0 mm/slub.c:5672
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4610 [inline]
slab_alloc_node mm/slub.c:4939 [inline]
kmem_cache_alloc_noprof+0x2b8/0x650 mm/slub.c:4946
lsm_file_alloc security/security.c:171 [inline]
security_file_alloc+0x34/0x310 security/security.c:2406
init_file+0x90/0x2b0 fs/file_table.c:184
alloc_empty_file+0x74/0x1d0 fs/file_table.c:266
path_openat+0x8f/0x3830 fs/namei.c:4845
do_file_open+0x23e/0x4a0 fs/namei.c:4888
do_sys_openat2+0x115/0x200 fs/open.c:1395
do_sys_open fs/open.c:1401 [inline]
__do_sys_openat fs/open.c:1417 [inline]
__se_sys_openat fs/open.c:1412 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1412
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc8b739c17c
RSP: 002b:00007ffecb6c1ef0 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000293 RCX: 00007fc8b739c17c
RDX: 0000000000090800 RSI: 00007fc8b74326b1 RDI: 00000000ffffff9c
RBP: 00007ffecb6c1f9c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00000000000000dc
R13: 0000000000000000 R14: 000000000007db2b R15: 00007ffecb6c1ff0
rcu: rcu_preempt kthread starved for 10093 jiffies! g113981 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:28152 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7322
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
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: 3226 Comm: kworker/R-bat_e Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:lock_acquire+0x5/0x350 kernel/locking/lockdep.c:5828
Code: a9 00 ff ff 00 0f 95 c0 e9 88 04 09 0a cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 60 4d 89 ce 45 89 c7 41 89 cc
RSP: 0018:ffffc90000006e88 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff81b105c9 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e959a20
RBP: 1ffff92000000df0 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000006f98 R11: ffffffff81b10630 R12: dffffc0000000000
R13: ffffffff8176a21f R14: ffffc90000006f48 R15: 1ffff92000000de9
FS: 0000000000000000(0000) GS:ffff88812527c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556a71a2aa38 CR3: 00000000750a8000 CR4: 00000000003526f0
Call Trace:
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:840 [inline]
class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0xac/0x2550 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4610 [inline]
slab_alloc_node mm/slub.c:4939 [inline]
kmem_cache_alloc_noprof+0x2b8/0x650 mm/slub.c:4946
skb_clone+0x212/0x3a0 net/core/skbuff.c:2110
deliver_clone net/bridge/br_forward.c:125 [inline]
maybe_deliver net/bridge/br_forward.c:191 [inline]
br_flood+0x3c3/0x8d0 net/bridge/br_forward.c:245
br_handle_frame_finish+0x1175/0x1990 net/bridge/br_input.c:229
br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1
br_nf_pre_routing_finish_ipv6+0x90c/0xc40 net/bridge/br_netfilter_ipv6.c:-1
NF_HOOK include/linux/netfilter.h:318 [inline]
br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
br_handle_frame+0x127f/0x1510 net/bridge/br_input.c:442
__netif_receive_skb_core+0x989/0x30b0 net/core/dev.c:6093
__netif_receive_skb_one_core net/core/dev.c:6204 [inline]
__netif_receive_skb net/core/dev.c:6319 [inline]
process_backlog+0x706/0x1860 net/core/dev.c:6670
__napi_poll+0xaa/0x330 net/core/dev.c:7729
napi_poll net/core/dev.c:7792 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:7949
handle_softirqs+0x225/0x840 kernel/softirq.c:622
do_softirq+0x76/0xd0 kernel/softirq.c:523
__local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_tt_global_purge net/batman-adv/translation-table.c:2298 [inline]
batadv_tt_purge+0x4ae/0xa10 net/batman-adv/translation-table.c:3558
process_one_work kernel/workqueue.c:3314 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397
rescuer_thread+0x7b6/0x10b0 kernel/workqueue.c:3621
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