rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P19895/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=154145, q=1617 ncpus=2)
task:syz.1.3661 state:R running task stack:23624 pid:19895 tgid:19889 ppid:16567 task_flags:0x400040 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872
Code: e9 30 ff ff ff e8 45 85 0d 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 c1 d2 7a 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d fe 84 73
RSP: 0018:ffffc9000357f298 EFLAGS: 00000282
RAX: ee144715b8eccf00 RBX: 0000000000000246 RCX: 0000000000000046
RDX: 0000000054d6a3fe RSI: ffffffff8e16a649 RDI: ffffffff8c27cb80
RBP: 0000000000000000 R08: ffffffff81767e95 R09: ffffffff8e75e5e0
R10: ffffc9000357f3f8 R11: ffffffff81b0d030 R12: 0000000000000002
R13: ffffffff8e75e5e0 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0xc2/0x23c0 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
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
__free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978
__slab_free+0x263/0x2b0 mm/slub.c:5573
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5380
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
kobject_uevent_env+0x28c/0x9e0 lib/kobject_uevent.c:540
__loop_clr_fd drivers/block/loop.c:1146 [inline]
lo_release+0x469/0x840 drivers/block/loop.c:1751
bdev_release+0x536/0x650 block/bdev.c:-1
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x44f/0xa70 fs/file_table.c:469
task_work_run+0x1d9/0x270 kernel/task_work.c:233
get_signal+0x11eb/0x1330 kernel/signal.c:2807
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff6e8f9c799
RSP: 002b:00007ff6e9ecf028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007ff6e9216090 RCX: 00007ff6e8f9c799
RDX: 00002000000002c0 RSI: 0000000000004c0a RDI: 0000000000000009
RBP: 00007ff6e9032c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff6e9216128 R14: 00007ff6e9216090 R15: 00007ff6e933fa48
rcu: rcu_preempt kthread starved for 215 jiffies! g154145 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:27648 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 18710 Comm: kworker/u8:3 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker
RIP: 0010:memset_orig+0x8a/0xb0 arch/x86/lib/memset_64.S:106
Code: 89 d1 83 e1 38 74 14 c1 e9 03 66 0f 1f 44 00 00 ff c9 48 89 07 48 8d 7f 08 75 f5 83 e2 07 74 0a ff ca 88 07 48 8d 7f 01 75 f6 <4c> 89 d0 c3 cc cc cc cc 48 83 fa 07 76 e3 48 89 07 49 c7 c0 08 00
RSP: 0018:ffffc90000007648 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000820 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880ac6b91b8
RBP: ffff8880b8643200 R08: 00000000591c7f67 R09: 0000000000000000
R10: ffff8880ac6b9100 R11: ffffffff81b0d030 R12: ffffffff8978cda8
R13: ffff8880ac6b9100 R14: ffff88801f2b2c80 R15: 00000000000000b8
FS: 0000000000000000(0000) GS:ffff88812545a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f40d91456b8 CR3: 0000000032ff2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
slab_post_alloc_hook mm/slub.c:4541 [inline]
slab_alloc_node mm/slub.c:4866 [inline]
kmem_cache_alloc_noprof+0x2e0/0x650 mm/slub.c:4873
__skb_ext_alloc net/core/skbuff.c:7074 [inline]
skb_ext_add+0x148/0x8f0 net/core/skbuff.c:7178
nf_bridge_alloc include/net/netfilter/br_netfilter.h:12 [inline]
br_nf_pre_routing_ipv6+0x12e/0x6f0 net/bridge/br_netfilter_ipv6.c:172
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
br_handle_frame+0x1277/0x1510 net/bridge/br_input.c:442
__netif_receive_skb_core+0x98f/0x31a0 net/core/dev.c:6063
__netif_receive_skb_one_core net/core/dev.c:6174 [inline]
__netif_receive_skb net/core/dev.c:6289 [inline]
process_backlog+0x76d/0x1950 net/core/dev.c:6640
__napi_poll+0xae/0x340 net/core/dev.c:7704
napi_poll net/core/dev.c:7767 [inline]
net_rx_action+0x627/0xf70 net/core/dev.c:7924
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
do_softirq+0x76/0xd0 kernel/softirq.c:523
__local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
blake2s_compress+0xf9/0x1eb0 lib/crypto/x86/blake2s.h:42
blake2s_update+0x14b/0x450 lib/crypto/blake2s.c:119
hmac+0x2d3/0x3b0 drivers/net/wireguard/noise.c:332
kdf+0xff/0x2b0 drivers/net/wireguard/noise.c:360
mix_precomputed_dh drivers/net/wireguard/noise.c:426 [inline]
wg_noise_handshake_create_initiation+0x473/0x830 drivers/net/wireguard/noise.c:560
wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:34 [inline]
wg_packet_handshake_send_worker+0x18d/0x350 drivers/net/wireguard/send.c:51
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
net_ratelimit: 7807 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1a:62:af:02:e5:2a, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1a:62:af:02:e5:2a, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1a:62:af:02:e5:2a, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 7886 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1a:62:af:02:e5:2a, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1a:62:af:02:e5:2a, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:1a:62:af:02:e5:2a, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)