rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5639/1:b..l..
rcu: (detected by 0, t=10503 jiffies, g=43489, q=1054161 ncpus=2)
task:syz-executor state:R running task stack:21920 pid:5639 tgid:5639 ppid:1 task_flags:0x40054c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 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:__page_table_check_zero+0x185/0x430 mm/page_table_check.c:-1
Code: 00 00 89 e9 d3 e3 48 8b 7c 24 08 e8 45 f4 ff ff 48 85 c0 0f 84 af 01 00 00 49 89 c5 4c 89 3c 24 4c 63 fb 89 e8 48 89 44 24 10 <41> bc 01 00 00 00 48 c7 c0 e0 54 fb 9b 48 c1 e8 03 48 89 44 24 18
RSP: 0018:ffffc90003fb72d8 EFLAGS: 00000286
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88807f211f40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff824c5ddc R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100701bba4 R12: ffffea0001d0d480
R13: ffff8880201509a0 R14: 0000000000074352 R15: 0000000000000001
page_table_check_free include/linux/page_table_check.h:46 [inline]
__free_pages_prepare mm/page_alloc.c:1404 [inline]
free_unref_folios+0xdd6/0x14e0 mm/page_alloc.c:3017
folios_put_refs+0x9e9/0xb30 mm/folio.c:1039
free_pages_and_swap_cache+0x2ba/0x490 mm/swap_state.c:654
__tlb_batch_free_encoded_pages mm/mmu_gather.c:138 [inline]
tlb_batch_pages_flush mm/mmu_gather.c:151 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0x6d3/0xa30 mm/mmu_gather.c:404
tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:529
exit_mmap+0x4b2/0xa40 mm/mmap.c:1328
__mmput+0x118/0x420 kernel/fork.c:1192
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+0x136a/0x1430 kernel/signal.c:3113
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: 0033:0x7f49c155fd8e
RSP: 002b:00007ffeb344fd68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: 0000000000000000 RBX: 0000555578b40500 RCX: 00007f49c155fd8e
RDX: 00007ffeb344fdc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffeb344fe2c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000092
R13: 0000000000000004 R14: 0000000000036262 R15: 00007ffeb344fe80
rcu: rcu_preempt kthread starved for 705 jiffies! g43489 f0x2 RCU_GP_WAIT_FQS(5) ->state=R ->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:26752 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 46 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
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:__rcu_read_unlock+0x69/0xe0 kernel/rcu/tree_plugin.h:443
Code: 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 75 66 41 83 3e 00 75 27 43 0f b6 04 3c 84 c0 75 41 8b 03 3d 00 00 00 40 73 0f <5b> 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc cc 90 0f 0b 90 eb eb e8
RSP: 0018:ffffc90000a37f10 EFLAGS: 00000283
RAX: 0000000000000002 RBX: ffff888021ee84c4 RCX: 8000000000000101
RDX: ffffc90000a38001 RSI: ffffffff8ea7ab24 RDI: ffff888021ee8000
RBP: 1ffffffff252eb01 R08: ffffc90000b67308 R09: 0000000000000000
R10: ffffc90000a38038 R11: fffff52000147009 R12: 1ffff110043dd098
R13: ffffffff8178a98f R14: ffffc90000a37fe8 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888123476000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff570a31ff8 CR3: 000000000ff48000 CR4: 00000000003526f0
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:882 [inline]
class_rcu_destructor include/linux/rcupdate.h:1216 [inline]
unwind_next_frame+0x1baf/0x2550 arch/x86/kernel/unwind_orc.c:709
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
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:264 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2780 [inline]
slab_free mm/slub.c:6630 [inline]
kfree+0x1c5/0x650 mm/slub.c:6923
skb_release_all net/core/skbuff.c:1188 [inline]
__kfree_skb+0x5d/0x210 net/core/skbuff.c:1202
nft_synproxy_eval_v4+0x36a/0x4e0 net/netfilter/nft_synproxy.c:-1
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_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:633
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:6433 [inline]
__netif_receive_skb net/core/dev.c:6546 [inline]
process_backlog+0xa6b/0x18b0 net/core/dev.c:6897
__napi_poll+0xaa/0x330 net/core/dev.c:7966
napi_poll net/core/dev.c:8029 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:8186
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+0x1f4/0x3b0 drivers/net/wireguard/noise.c:324
kdf+0x12d/0x290 drivers/net/wireguard/noise.c:367
mix_precomputed_dh drivers/net/wireguard/noise.c:426 [inline]
wg_noise_handshake_create_initiation+0x460/0x810 drivers/net/wireguard/noise.c:560
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:3495 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
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