rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P43/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=21521, q=100376 ncpus=2)
task:kworker/1:1 state:R running task stack:21720 pid:43 tgid:43 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: events free_obj_work
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288
irqentry_exit+0x36/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:unwind_next_frame+0xd4f/0x20a0 arch/x86/kernel/unwind_orc.c:590
Code: 03 4c 8b 44 24 28 80 3c 16 00 0f 85 d3 0e 00 00 48 8b 14 24 49 89 45 48 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 <0f> 85 c6 12 00 00 4c 89 e2 4d 89 75 38 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc90000b37708 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff914f4e5a
RDX: 1ffff92000166ef6 RSI: 1ffff92000166ef8 RDI: ffffc90000b37ac0
RBP: ffffc90000b377c0 R08: ffffffff914f4e5e R09: 0000000000000000
R10: 0000000000000002 R11: 00000000000121b1 R12: ffffc90000b377c8
R13: ffffc90000b37778 R14: ffffc90000b37ac8 R15: ffffc90000b377ac
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:243 [inline]
__kasan_slab_free+0x60/0x70 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2417 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4782
free_object_list.isra.0+0xf8/0x2a0 lib/debugobjects.c:326
free_obj_work+0x19f/0x3d0 lib/debugobjects.c:513
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 252 jiffies! g21521 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:27672 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6013 Comm: kworker/0:7 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: wg-kex-wg0 wg_packet_handshake_receive_worker
RIP: 0010:kasan_check_byte include/linux/kasan.h:399 [inline]
RIP: 0010:lock_acquire kernel/locking/lockdep.c:5842 [inline]
RIP: 0010:lock_acquire+0xf4/0x350 kernel/locking/lockdep.c:5825
Code: 44 89 f2 48 89 de e8 5b d0 fe ff 5f 41 58 65 ff 0d 61 a8 3e 12 0f 85 4f ff ff ff e8 d6 ad 94 ff e9 45 ff ff ff 48 8b 74 24 68 <48> 89 df e8 54 f5 89 00 8b 0d 62 b6 13 0f 85 c9 0f 84 b1 00 00 00
RSP: 0018:ffffc90000007018 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff8e5c1220 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff89c33c56 RDI: ffffffff8df5ee60
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881246b9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3774554ff8 CR3: 0000000032ed5000 CR4: 00000000003526f0
Call Trace:
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
net_generic+0x36/0x2a0 include/net/netns/generic.h:45
synproxy_pernet include/net/netfilter/nf_synproxy.h:32 [inline]
ipv6_synproxy_hook+0xb7/0x1f90 net/netfilter/nf_synproxy_core.c:1060
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
nf_hook+0x45e/0x780 include/linux/netfilter.h:273
NF_HOOK_COND include/linux/netfilter.h:306 [inline]
ip6_output+0x255/0x3e0 net/ipv6/ip6_output.c:248
dst_output include/net/dst.h:461 [inline]
ip6_local_out+0xd1/0x4d0 net/ipv6/output_core.c:155
synproxy_send_tcp_ipv6+0x59e/0x680 net/netfilter/nf_synproxy_core.c:851
synproxy_send_client_synack_ipv6+0x635/0x7e0 net/netfilter/nf_synproxy_core.c:897
nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:90 [inline]
nft_synproxy_do_eval+0x93b/0xd80 net/netfilter/nft_synproxy.c:145
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e6/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x18a/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
nf_hook.constprop.0+0x422/0x750 include/linux/netfilter.h:273
NF_HOOK include/linux/netfilter.h:316 [inline]
ip6_input+0xe0/0x2f0 net/ipv6/ip6_input.c:500
dst_input include/net/dst.h:471 [inline]
ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ipv6_rcv+0x264/0x650 net/ipv6/ip6_input.c:311
__netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5991
__netif_receive_skb+0x1d/0x160 net/core/dev.c:6104
process_backlog+0x442/0x15e0 net/core/dev.c:6456
__napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7506
napi_poll net/core/dev.c:7569 [inline]
net_rx_action+0xa9f/0xfe0 net/core/dev.c:7696
handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
do_softirq kernel/softirq.c:480 [inline]
do_softirq+0xb2/0xf0 kernel/softirq.c:467
__local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407
local_bh_enable include/linux/bottom_half.h:33 [inline]
fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline]
kernel_fpu_end+0x5e/0x70 arch/x86/kernel/fpu/core.c:479
blake2s_compress+0x7f/0xe0 lib/crypto/x86/blake2s-glue.c:46
blake2s_final+0xc9/0x150 lib/crypto/blake2s.c:55
mix_hash+0xfa/0x140 drivers/net/wireguard/noise.c:439
message_ephemeral+0x46/0x70 drivers/net/wireguard/noise.c:492
wg_noise_handshake_create_response+0x37c/0x640 drivers/net/wireguard/noise.c:692
wg_packet_send_handshake_response+0xe0/0x310 drivers/net/wireguard/send.c:94
wg_receive_handshake_packet+0x247/0xbf0 drivers/net/wireguard/receive.c:154
wg_packet_handshake_receive_worker+0x17f/0x3a0 drivers/net/wireguard/receive.c:213
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245