rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4331/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=23517, q=1369272 ncpus=1)
task:klogd           state:R  running task     stack:0     pid:4331  tgid:4331  ppid:1      task_flags:0x400100 flags:0x00000010
Call trace:
 __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5533 [inline]
 __schedule+0x135c/0x2b00 kernel/sched/core.c:7284
 preempt_schedule_common+0xd4/0x190 kernel/sched/core.c:7463
 preempt_schedule+0x60/0x78 kernel/sched/core.c:7487
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
 _raw_spin_unlock_irqrestore+0x94/0x98 kernel/locking/spinlock.c:221
 spin_unlock_irqrestore include/linux/spinlock.h:425 [inline]
 __wake_up_common_lock+0x5c/0x78 kernel/sched/wait.c:128
 __wake_up_sync_key+0x20/0x2c kernel/sched/wait.c:193
 sock_def_readable+0x208/0x5d0 net/core/sock.c:3668
 unix_dgram_sendmsg+0xbb8/0x1078 net/unix/af_unix.c:2300
 sock_sendmsg_nosec net/socket.c:800 [inline]
 __sock_sendmsg+0xc8/0x17c net/socket.c:815
 __sys_sendto+0x250/0x328 net/socket.c:2281
 __do_sys_sendto net/socket.c:2288 [inline]
 __se_sys_sendto net/socket.c:2284 [inline]
 __arm64_sys_sendto+0xec/0x10c net/socket.c:2284
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606
rcu: rcu_preempt kthread starved for 372 jiffies! g23517 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:0     pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00000010
Call trace:
 __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5533 [inline]
 __schedule+0x135c/0x2b00 kernel/sched/core.c:7284
 __schedule_loop kernel/sched/core.c:7361 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7376
 schedule_timeout+0x13c/0x28c kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x260/0xde8 kernel/rcu/tree.c:2122
 rcu_gp_kthread+0x148/0x230 kernel/rcu/tree.c:2330
 kthread+0x304/0x3d4 kernel/kthread.c:436
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:854
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 2857 Comm: kworker/R-bat_e Tainted: G             L      syzkaller #0 PREEMPT 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
Workqueue: bat_events batadv_tt_purge
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : should_resched arch/arm64/include/asm/preempt.h:80 [inline]
pc : __local_bh_enable_ip+0x150/0x234 kernel/softirq.c:480
lr : __local_bh_enable_ip+0x14c/0x234 kernel/softirq.c:478
sp : ffff80008ea96ce0
x29: ffff80008ea96ce0 x28: ffff0000cfa56040 x27: 1fffe00019f4ac38
x26: ffff8000878e3fa0 x25: ffff000056a61780 x24: ffff00005751b200
x23: dfff800000000000 x22: 1fffe000198f2b11 x21: ffff8000855b5e8c
x20: 0000000000000200 x19: ffff0000cc795888 x18: ffff8001254c8000
x17: ffff0001adee5e07 x16: 00000000002f2543 x15: 00000000002f2544
x14: 0000000004b2e7f1 x13: 0000000000000004 x12: 0000000000000003
x11: ffff80008a506e28 x10: 0000000000000003 x9 : 0000000000000001
x8 : 00000000051a56dc x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000008 x3 : ffff8000801556d8
x2 : 0000000000000002 x1 : ffff0000cc795880 x0 : ffff8001254c8000
Call trace:
 __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline] (P)
 arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline] (P)
 __local_bh_enable_ip+0x150/0x234 kernel/softirq.c:478 (P)
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 ipt_do_table+0x103c/0x1288 net/ipv4/netfilter/ip_tables.c:357
 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
 nf_hook_slow+0xc8/0x224 net/netfilter/core.c:619
 nf_hook+0x1f0/0x364 include/linux/netfilter.h:280
 __ip_local_out+0x4e8/0x5c8 net/ipv4/ip_output.c:120
 ip_local_out+0x3c/0x148 net/ipv4/ip_output.c:129
 synproxy_send_tcp+0x3ec/0x5a4 net/netfilter/nf_synproxy_core.c:442
 synproxy_send_client_synack+0x3b0/0x640 net/netfilter/nf_synproxy_core.c:487
 nft_synproxy_eval_v4+0x16c/0x278 net/netfilter/nft_synproxy.c:59
 nft_synproxy_do_eval+0x2d8/0x4a4 net/netfilter/nft_synproxy.c:141
 nft_synproxy_eval+0x34/0x48 net/netfilter/nft_synproxy.c:247
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x418/0x13c8 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x284/0x3d4 net/netfilter/nft_chain_filter.c:162
 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
 nf_hook_slow+0xc8/0x224 net/netfilter/core.c:619
 nf_hook include/linux/netfilter.h:280 [inline]
 NF_HOOK+0x1f0/0x398 include/linux/netfilter.h:323
 ip_local_deliver+0x128/0x188 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:480 [inline]
 ip_rcv_finish+0x20c/0x230 net/ipv4/ip_input.c:492
 NF_HOOK+0x308/0x398 include/linux/netfilter.h:325
 ip_rcv+0x7c/0x9c net/ipv4/ip_input.c:612
 __netif_receive_skb_one_core+0xc8/0x110 net/core/dev.c:6264
 __netif_receive_skb+0x34/0x128 net/core/dev.c:6377
 process_backlog+0x588/0x14e0 net/core/dev.c:6728
 __napi_poll+0xb4/0x328 net/core/dev.c:7787
 napi_poll net/core/dev.c:7850 [inline]
 net_rx_action+0x5b0/0xc14 net/core/dev.c:8007
 handle_softirqs+0x324/0xcbc kernel/softirq.c:645
 __do_softirq+0x14/0x20 kernel/softirq.c:679
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:78
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:901
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:83
 do_softirq+0x90/0xf8 kernel/softirq.c:546
 __local_bh_enable_ip+0x190/0x234 kernel/softirq.c:473
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:237 [inline]
 _raw_spin_unlock_bh+0x3c/0x4c kernel/locking/spinlock.c:245
 spin_unlock_bh include/linux/spinlock.h:407 [inline]
 batadv_tt_global_purge net/batman-adv/translation-table.c:2390 [inline]
 batadv_tt_purge+0x3e4/0x7b4 net/batman-adv/translation-table.c:3754
 process_one_work kernel/workqueue.c:3396 [inline]
 process_scheduled_works+0x91c/0x1250 kernel/workqueue.c:3479
 rescuer_thread+0x68c/0xd90 kernel/workqueue.c:3703
 kthread+0x304/0x3d4 kernel/kthread.c:436
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:854