rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16548/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=231245, q=1062711 ncpus=1)
task:syz.0.2560 state:R running task stack:25352 pid:16548 tgid:16544 ppid:15829 task_flags:0x40044c flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7554
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14f/0x910 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_is_held_type+0x106/0x150 kernel/locking/lockdep.c:5987
Code: 1b 00 00 b8 ff ff ff ff 65 0f c1 05 6c 4e 96 07 83 f8 01 75 25 9c 58 a9 00 02 00 00 75 39 41 f7 c4 00 02 00 00 74 01 fb 89 d8 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 90 0f 0b 90 48 c7
RSP: 0018:ffffc900057e7088 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000046
RDX: 0000000000000000 RSI: ffffffff8e4d9480 RDI: ffffffff8c4c7680
RBP: 00000000ffffffff R08: 0800000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8eb5c6a0 R12: 0000000000000246
R13: ffff88802335ddc0 R14: ffffffff8eb5c6a0 R15: 0000000000000000
lookup_page_ext mm/page_ext.c:253 [inline]
page_ext_get+0x1b0/0x2e0 mm/page_ext.c:523
__reset_page_owner+0x28/0x1f0 mm/page_owner.c:324
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
free_unref_folios+0xdc2/0x14e0 mm/page_alloc.c:3080
folios_put_refs+0x9e9/0xb30 mm/folio.c:1034
folio_batch_release include/linux/folio_batch.h:101 [inline]
shmem_undo_range+0x4e6/0x15d0 mm/shmem.c:1160
shmem_truncate_range mm/shmem.c:1288 [inline]
shmem_evict_inode+0x247/0xae0 mm/shmem.c:1419
evict+0x624/0xb50 fs/inode.c:822
dentry_kill+0x1b9/0x880 fs/dcache.c:826
finish_dput+0x1a/0x260 fs/dcache.c:1001
__fput+0x675/0xa50 fs/file_table.c:520
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x73a/0x2360 kernel/exit.c:1008
do_group_exit+0x22d/0x2f0 kernel/exit.c:1151
get_signal+0x121b/0x12c0 kernel/signal.c:3039
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x138/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline]
do_syscall_64+0x328/0x510 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb8b1d5e90e
RSP: 002b:00007fb8b2d1cda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: 0000000000f89000 RBX: 00007fb8b2d1d6c0 RCX: 00007fb8b1d5e90e
RDX: 0000000001000000 RSI: 00007fb8a7a00000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fb8b2d1cee0 R14: 00007fb8b2d1cea0 R15: 00007fb8a7a00000
rcu: rcu_preempt kthread starved for 4701 jiffies! g231245 f0x2 RCU_GP_WAIT_FQS(5) ->state=R ->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:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232
__schedule_loop kernel/sched/core.c:7309 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7324
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
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: 3227 Comm: kworker/R-bat_e Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: bat_events batadv_dat_purge
RIP: 0010:check_preemption_disabled+0x22/0xe0 lib/smp_processor_id.c:53
Code: 90 90 90 90 90 90 90 90 55 41 57 41 56 53 65 8b 05 47 ee 95 07 65 8b 0d 3c ee 95 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d 99 e5 02 00 cc 9c 59 f7 c1 00 02 00 00 74 ea 65 4c 8b 3d ee ed
RSP: 0018:ffffc900000067a0 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000080000102
RDX: 0000000000000000 RSI: ffffffff8c4c7660 RDI: ffffffff8c4c7620
RBP: 1ffff92000000d28 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000006958 R11: ffffffff81b243c0 R12: ffffffff8eb5c6a0
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124f0c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555560b364e8 CR3: 000000007f580000 CR4: 00000000003526f0
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:753
trace_lock_acquire include/trace/events/lock.h:23 [inline]
lock_acquire+0x58/0x350 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
class_rcu_constructor include/linux/rcupdate.h:1216 [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
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x31d/0x600 mm/slub.c:5563
_kmalloc_noprof include/linux/slab.h:991 [inline]
_kzalloc_noprof include/linux/slab.h:1312 [inline]
ref_tracker_alloc+0x15b/0x4b0 lib/ref_tracker.c:270
__netdev_tracker_alloc include/linux/netdevice.h:4522 [inline]
netdev_hold include/linux/netdevice.h:4551 [inline]
dst_init+0xbe/0x470 net/core/dst.c:52
dst_alloc+0x12a/0x170 net/core/dst.c:94
rt_dst_alloc net/ipv4/route.c:1652 [inline]
__mkroute_output net/ipv4/route.c:2655 [inline]
ip_route_output_key_hash_rcu+0x14ac/0x2720 net/ipv4/route.c:2875
ip_route_output_key_hash+0x18d/0x2a0 net/ipv4/route.c:2705
__ip_route_output_key include/net/route.h:169 [inline]
ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2932
ip_route_output_key include/net/route.h:179 [inline]
ip_route_me_harder+0x762/0xfe0 net/ipv4/netfilter.c:54
synproxy_send_tcp+0x347/0x670 net/netfilter/nf_synproxy_core.c:434
synproxy_send_client_synack+0x89b/0xde0 net/netfilter/nf_synproxy_core.c:487
nft_synproxy_eval_v4+0x362/0x4e0 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x335/0x550 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x48d/0x1b10 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
nf_hook include/linux/netfilter.h:280 [inline]
NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:323
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:325
__netif_receive_skb_one_core net/core/dev.c:6241 [inline]
__netif_receive_skb net/core/dev.c:6354 [inline]
process_backlog+0xa34/0x1860 net/core/dev.c:6705
__napi_poll+0xaa/0x330 net/core/dev.c:7764
napi_poll net/core/dev.c:7827 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:7984
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_dat_purge net/batman-adv/distributed-arp-table.c:186 [inline]
batadv_dat_purge+0x2d7/0x3c0 net/batman-adv/distributed-arp-table.c:205
process_one_work kernel/workqueue.c:3375 [inline]
process_scheduled_works+0xc4e/0x1630 kernel/workqueue.c:3458
rescuer_thread+0x7c5/0x10e0 kernel/workqueue.c:3682
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