lec0: NETDEV WATCHDOG: CPU: 1: transmit queue 0 timed out 5680 ms
lec:lec_tx_timeout: lec0
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P21223/3:b..l
rcu: (detected by 1, t=10502 jiffies, g=412309, q=941649 ncpus=2)
task:syz.4.14175 state:R running task stack:27000 pid:21223 tgid:21221 ppid:14883 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7091
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__local_bh_enable_ip+0xff/0x120 kernel/softirq.c:457
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
__dev_queue_xmit+0x8b5/0x4800 net/core/dev.c:4876
dev_queue_xmit include/linux/netdevice.h:3384 [inline]
neigh_hh_output include/net/neighbour.h:540 [inline]
neigh_output include/net/neighbour.h:554 [inline]
ip_finish_output2+0xf4a/0x24d0 net/ipv4/ip_output.c:237
__ip_finish_output.part.0+0x444/0x6f0 net/ipv4/ip_output.c:315
__ip_finish_output net/ipv4/ip_output.c:303 [inline]
ip_finish_output net/ipv4/ip_output.c:325 [inline]
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x39b/0xec0 net/ipv4/ip_output.c:438
dst_output include/net/dst.h:470 [inline]
ip_local_out net/ipv4/ip_output.c:131 [inline]
__ip_queue_xmit+0x1b73/0x22b0 net/ipv4/ip_output.c:534
__tcp_transmit_skb+0x3347/0x4b50 net/ipv4/tcp_output.c:1693
tcp_transmit_skb net/ipv4/tcp_output.c:1711 [inline]
tcp_send_syn_data net/ipv4/tcp_output.c:4287 [inline]
tcp_connect+0x2956/0x5630 net/ipv4/tcp_output.c:4376
tcp_v4_connect+0x158b/0x1bf0 net/ipv4/tcp_ipv4.c:347
__inet_stream_connect+0x208/0xfa0 net/ipv4/af_inet.c:679
tcp_sendmsg_fastopen+0x3ed/0x750 net/ipv4/tcp.c:1098
tcp_sendmsg_locked+0x279a/0x45f0 net/ipv4/tcp.c:1194
tcp_sendmsg+0x2e/0x50 net/ipv4/tcp.c:1464
inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:859
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x467/0x520 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4b26b9c799
RSP: 002b:00007f4b24df6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f4b26e15fa0 RCX: 00007f4b26b9c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f4b26c32bd9 R08: 0000200000e68000 R09: 0000000000000010
R10: 00000000200007fd R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4b26e16038 R14: 00007f4b26e15fa0 R15: 00007ffcfc365548
rcu: rcu_preempt kthread starved for 5429 jiffies! g412309 f0x2 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:28680 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7004
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:unwind_next_frame+0x15b4/0x1ea0 arch/x86/kernel/unwind_orc.c:680
Code: b4 06 00 00 49 8b 45 10 48 39 dd 0f 87 c4 f8 ff ff 48 39 d8 0f 86 bb f8 ff ff 48 8d 53 08 48 39 d5 0f 92 c1 48 39 d0 0f 93 c0 <84> c1 0f 84 a3 f8 ff ff 48 39 5c 24 10 0f 82 98 f8 ff ff 48 b8 00
RSP: 0018:ffffc90000006ea8 EFLAGS: 00000206
RAX: ffffc90000008001 RBX: ffffc90000007008 RCX: ffffffff91770301
RDX: ffffc90000007010 RSI: ffffc90000006ff8 RDI: ffffc90000006f78
RBP: ffffc90000000000 R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 000000000000af0b R12: ffffc90000006fb8
R13: ffffc90000006f68 R14: ffffc90000007008 R15: ffffc90000006f9c
FS: 0000000000000000(0000) GS:ffff888124347000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd1e19dfc8 CR3: 00000000afd30000 CR4: 00000000003526f0
Call Trace:
__unwind_start+0x3d1/0x7f0 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0x73/0xf0 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4515 [inline]
slab_alloc_node mm/slub.c:4844 [inline]
kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4851
kmem_alloc_batch+0x49/0x170 lib/debugobjects.c:371
fill_pool lib/debugobjects.c:403 [inline]
debug_objects_fill_pool lib/debugobjects.c:725 [inline]
debug_objects_fill_pool+0x40e/0x670 lib/debugobjects.c:697
debug_object_activate+0x103/0x490 lib/debugobjects.c:814
debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
__call_rcu_common.constprop.0+0x35/0x9b0 kernel/rcu/tree.c:3116
call_rcu_hurry include/linux/rcupdate.h:125 [inline]
dst_release net/core/dst.c:178 [inline]
dst_release+0x259/0x330 net/core/dst.c:166
refdst_drop include/net/dst.h:272 [inline]
skb_dst_drop include/net/dst.h:284 [inline]
skb_release_head_state+0x293/0x400 net/core/skbuff.c:1177
skb_release_all net/core/skbuff.c:1201 [inline]
__kfree_skb net/core/skbuff.c:1217 [inline]
consume_skb net/core/skbuff.c:1450 [inline]
consume_skb+0x8a/0x110 net/core/skbuff.c:1444
nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:61 [inline]
nft_synproxy_do_eval+0xa7b/0xd50 net/netfilter/nft_synproxy.c:142
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e8/0x1930 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0xee/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623
nf_hook.constprop.0+0x2a6/0x750 include/linux/netfilter.h:273
NF_HOOK include/linux/netfilter.h:316 [inline]
ip_local_deliver+0x163/0x1f0 net/ipv4/ip_input.c:262
dst_input include/net/dst.h:480 [inline]
ip_rcv_finish net/ipv4/ip_input.c:453 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ip_rcv+0x2d9/0x5d0 net/ipv4/ip_input.c:573
__netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6167
__netif_receive_skb+0x1f/0x120 net/core/dev.c:6280
process_backlog+0x37a/0x1580 net/core/dev.c:6631
__napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7695
napi_poll net/core/dev.c:7758 [inline]
net_rx_action+0xa40/0xf20 net/core/dev.c:7910
handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: b8 82 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 dc 1b 00 fb f4 bc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e407e00 EFLAGS: 00000242
RAX: 0000000008c52cfd RBX: ffffffff8e4975c0 RCX: ffffffff8b8fac75
RDX: 0000000000000000 RSI: ffffffff8de72aee RDI: ffffffff8c1af220
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1017086795
R10: ffff8880b8433cab R11: 0000000000000000 R12: fffffbfff1c92eb8
R13: 0000000000000000 R14: ffffffff90d97a10 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x35b/0x4b0 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x251/0x260 init/main.c:760
start_kernel+0x47f/0x480 init/main.c:1210
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148