rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7227/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=18521, q=583273 ncpus=2)
task:syz.4.240 state:R running task stack:24104 pid:7227 tgid:7227 ppid:5844 task_flags:0x40004c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5313 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7019
irqentry_exit+0x6f/0x90 kernel/entry/common.c:196
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5896
Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 db 84 02 11 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90019d6ef50 EFLAGS: 00000206
RAX: 099ad94a4ce38d00 RBX: 0000000000000202 RCX: 099ad94a4ce38d00
RDX: 0000000000000000 RSI: ffffffff8db8215e RDI: ffffffff8be326c0
RBP: ffff88807c38c6f0 R08: ffffc90019d6fbc0 R09: 0000000000000000
R10: ffffc90019d6f0d8 R11: fffff520033ade1d R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8e13bfe0 R15: ffff88807c38bc00
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
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:1392 [inline]
free_unref_folios+0xd77/0x1570 mm/page_alloc.c:2949
folios_put_refs+0x559/0x640 mm/swap.c:992
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1125
shmem_truncate_range mm/shmem.c:1237 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1365
evict+0x501/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d1/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x2300 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1100
__do_sys_exit_group kernel/exit.c:1111 [inline]
__se_sys_exit_group kernel/exit.c:1109 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1109
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
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: 0033:0x7fe089d8e929
RSP: 002b:00007fff34bc1718 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe089d8e929
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff34bc177c R08: 0000001a34bc180f R09: 00000000000927c0
R10: 00000000000010fc R11: 0000000000000246 R12: 000000000000002c
R13: 00000000000927c0 R14: 000000000003808b R15: 00007fff34bc17d0
rcu: rcu_preempt kthread starved for 2557 jiffies! g18521 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:26632 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5313 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
__schedule_loop kernel/sched/core.c:6774 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6789
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2060
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2262
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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted 6.16.0-rc4-next-20250702-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:check_preemption_disabled+0x2d/0x120 lib/smp_processor_id.c:55
Code: 41 56 53 48 83 ec 10 65 48 8b 05 ae b6 30 07 48 89 44 24 08 65 8b 05 b6 b6 30 07 65 8b 0d ab b6 30 07 f7 c1 ff ff ff 7f 74 23 <65> 48 8b 0d 8b b6 30 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4
RSP: 0018:ffffc90000a07520 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000002 RCX: 0000000080000302
RDX: 0000000000000007 RSI: ffffffff8db8215e RDI: ffffffff8be326c0
RBP: ffff88801ce98c08 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff81a56440 R12: 0000000000000007
R13: 0000000000000007 R14: ffffffff99cdc688 R15: ffff88801ce98000
FS: 0000000000000000(0000) GS:ffff888125d1d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbaa3971d60 CR3: 0000000028688000 CR4: 00000000003526f0
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:473 [inline]
lock_release+0x27a/0x3e0 kernel/locking/lockdep.c:5894
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
_raw_spin_unlock_irqrestore+0x70/0x110 kernel/locking/spinlock.c:194
debug_object_activate+0x2e2/0x420 lib/debugobjects.c:836
debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
__call_rcu_common kernel/rcu/tree.c:3085 [inline]
call_rcu+0xaa/0x9c0 kernel/rcu/tree.c:3220
refdst_drop include/net/dst.h:263 [inline]
skb_dst_drop include/net/dst.h:275 [inline]
skb_release_head_state+0x71/0x250 net/core/skbuff.c:1136
skb_release_all net/core/skbuff.c:1150 [inline]
__kfree_skb net/core/skbuff.c:1166 [inline]
sk_skb_reason_drop+0xe9/0x170 net/core/skbuff.c:1204
kfree_skb_reason include/linux/skbuff.h:1275 [inline]
enqueue_to_backlog+0xbc/0xfa0 net/core/dev.c:5191
netif_rx_internal+0x130/0x560 net/core/dev.c:5489
__netif_rx+0x78/0xc0 net/core/dev.c:5509
loopback_xmit+0x47a/0x6f0 drivers/net/loopback.c:90
__netdev_start_xmit include/linux/netdevice.h:5217 [inline]
netdev_start_xmit include/linux/netdevice.h:5226 [inline]
xmit_one net/core/dev.c:3828 [inline]
dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3844
sch_direct_xmit+0x241/0x4b0 net/sched/sch_generic.c:344
qdisc_restart net/sched/sch_generic.c:409 [inline]
__qdisc_run+0xb16/0x15f0 net/sched/sch_generic.c:417
__dev_xmit_skb net/core/dev.c:4169 [inline]
__dev_queue_xmit+0xfe1/0x3a70 net/core/dev.c:4677
dev_queue_xmit include/linux/netdevice.h:3358 [inline]
neigh_hh_output include/net/neighbour.h:526 [inline]
neigh_output include/net/neighbour.h:540 [inline]
ip_finish_output2+0xd03/0x1160 net/ipv4/ip_output.c:235
synproxy_send_client_synack+0x8bb/0xe20 net/netfilter/nf_synproxy_core.c:484
nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x40c/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
nf_hook_slow+0xc2/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:272 [inline]
NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:315
NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:317
__netif_receive_skb_one_core net/core/dev.c:5975 [inline]
__netif_receive_skb+0x143/0x380 net/core/dev.c:6088
process_backlog+0x60e/0x14f0 net/core/dev.c:6440
__napi_poll+0xc7/0x480 net/core/dev.c:7453
napi_poll net/core/dev.c:7517 [inline]
net_rx_action+0x707/0xe30 net/core/dev.c:7644
handle_softirqs+0x286/0x870 kernel/softirq.c:579
do_softirq+0xec/0x180 kernel/softirq.c:480
__local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
ieee80211_rx_bss_info net/mac80211/ibss.c:1166 [inline]
ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1573 [inline]
ieee80211_ibss_rx_queued_mgmt+0x11e5/0x2ae0 net/mac80211/ibss.c:1600
ieee80211_iface_process_skb net/mac80211/iface.c:1668 [inline]
ieee80211_iface_work+0x806/0xfe0 net/mac80211/iface.c:1722
cfg80211_wiphy_work+0x2dc/0x460 net/wireless/core.c:435
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
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