rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P26267/1:b..l..
rcu: (detected by 1, t=10503 jiffies, g=283257, q=1745 ncpus=2)
task:syz.0.6080 state:R running task stack:26840 pid:26267 tgid:26266 ppid:16513 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7382
preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7662
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:543 [inline]
irqentry_exit+0x14f/0x9b0 kernel/entry/common.c:154
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:unwind_next_frame+0x482/0x2550 arch/x86/kernel/unwind_orc.c:520
Code: 04 48 89 54 24 18 4c 8d 6a 05 48 89 d8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 b4 19 00 00 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 bf 19 00 00 0f b6 43 01 83 e0 07 0f 84 7c 16 00 00 83
RSP: 0018:ffffc9000438f2a0 EFLAGS: 00000a03
RAX: 0000000000000000 RBX: ffffffff921f560c RCX: ffffffff919c40e0
RDX: ffffffff921f5608 RSI: ffffffff921f5608 RDI: ffffffff8c6e0220
RBP: ffffffff82224b3e R08: 0000000000000001 R09: 0000000000000000
R10: ffffc9000438f398 R11: ffffffff81b285d0 R12: dffffc0000000000
R13: ffffffff921f560d R14: ffffc9000438f348 R15: ffffffff919c40e0
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:409 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x31c/0x600 mm/slub.c:5563
_kmalloc_noprof include/linux/slab.h:991 [inline]
slab_free_hook mm/slub.c:2700 [inline]
slab_free mm/slub.c:6509 [inline]
kmem_cache_free+0x156/0x650 mm/slub.c:6636
tear_down_vmas+0x31f/0x530 mm/mmap.c:1277
exit_mmap+0x4ca/0x9f0 mm/mmap.c:1335
__mmput+0x118/0x420 kernel/fork.c:1193
exit_mm+0x18e/0x240 kernel/exit.c:586
do_exit+0x6a8/0x2360 kernel/exit.c:967
do_group_exit+0x22d/0x2f0 kernel/exit.c:1123
get_signal+0x1216/0x12c0 kernel/signal.c:3112
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+0x10e/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:343 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb5f5b9f559
RSP: 002b:00007fb5f6a6e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000000 RBX: 00007fb5f5e25fa8 RCX: 00007fb5f5b9f559
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fb5f5e25fa8
RBP: 00007fb5f5e25fa0 R08: 00007fb5f6a6e6c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fb5f5e26038 R14: 00007fb5f5f4f960 R15: 00007fb5f5f4fa48
rcu: rcu_preempt kthread starved for 969 jiffies! g283257 f0x0 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:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x1230 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9c/0x340 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7702 Comm: kworker/u8:15 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker
RIP: 0010:check_preemption_disabled+0x1/0xd0 lib/smp_processor_id.c:13
Code: 20 02 6e 8c 48 c7 c6 60 02 6e 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <41> 57 41 56 53 65 8b 05 eb 5b ab 08 65 48 8b 0d bb 5b ab 08 85 c9
RSP: 0018:ffffc90000006d78 EFLAGS: 00000086
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 00000000071bee9f RSI: ffffffff8e6f8834 RDI: ffffffff8c6e0280
RBP: ffff8880283b3e80 R08: ffffffff8178399f R09: 0000000000000000
R10: ffffc90000006f18 R11: ffffffff81b285d0 R12: ffffffff8fd58a60
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246
FS: 0000000000000000(0000) GS:ffff888123aa9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb12274eccc CR3: 000000000fb48000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
lock_acquire+0x125/0x350 kernel/locking/lockdep.c:5945
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
unpoison_slab_object mm/kasan/common.c:351 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:377
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
kmem_cache_alloc_node_noprof+0x34f/0x600 mm/slub.c:5068
__alloc_skb+0x1db/0x7a0 net/core/skbuff.c:704
alloc_skb include/linux/skbuff.h:1384 [inline]
synproxy_send_client_synack+0x175/0xde0 net/netfilter/nf_synproxy_core.c:463
nft_synproxy_eval_v4+0x362/0x4e0 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x389/0x5d0 net/netfilter/nft_synproxy.c:142
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_ipv4+0x195/0x290 net/netfilter/nft_chain_filter.c:24
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:6297 [inline]
__netif_receive_skb net/core/dev.c:6410 [inline]
process_backlog+0xa6b/0x18b0 net/core/dev.c:6761
__napi_poll+0xaa/0x330 net/core/dev.c:7830
napi_poll net/core/dev.c:7893 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:8050
handle_softirqs+0x265/0x8d0 kernel/softirq.c:669
do_softirq+0x77/0xd0 kernel/softirq.c:569
__local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473
blake2s_compress+0xfa/0x1c00 lib/crypto/x86/blake2s.h:42
blake2s_update+0x140/0x450 lib/crypto/blake2s.c:119
hmac+0x2d1/0x3b0 drivers/net/wireguard/noise.c:332
kdf drivers/net/wireguard/noise.c:367 [inline]
message_ephemeral+0x255/0x310 drivers/net/wireguard/noise.c:493
wg_noise_handshake_create_initiation+0x24f/0x810 drivers/net/wireguard/noise.c:545
wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:34 [inline]
wg_packet_handshake_send_worker+0x18c/0x370 drivers/net/wireguard/send.c:51
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x480 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