syzbot

watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [kworker/1:4:6520]
Modules linked in:
irq event stamp: 37763481
hardirqs last  enabled at (37763480): [<ffff80008b86338c>] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:85 [inline]
hardirqs last  enabled at (37763480): [<ffff80008b86338c>] exit_to_kernel_mode+0xdc/0x10c arch/arm64/kernel/entry-common.c:95
hardirqs last disabled at (37763481): [<ffff80008b860e04>] __el1_irq arch/arm64/kernel/entry-common.c:557 [inline]
hardirqs last disabled at (37763481): [<ffff80008b860e04>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:575
softirqs last  enabled at (5415542): [<ffff80008576c928>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (5415546): [<ffff800085777e98>] wg_socket_send_skb_to_peer+0x64/0x1a8 drivers/net/wireguard/socket.c:173
CPU: 1 UID: 0 PID: 6520 Comm: kworker/1:4 Not tainted 6.14.0-rc7-syzkaller-ga2392f333575 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: wg-crypt-wg0 wg_packet_tx_worker
pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : get_current arch/arm64/include/asm/current.h:19 [inline]
pc : write_comp_data kernel/kcov.c:245 [inline]
pc : __sanitizer_cov_trace_const_cmp4+0x8/0xa0 kernel/kcov.c:314
lr : cake_dequeue+0x43c/0x3da0 net/sched/sch_cake.c:2010
sp : ffff8000a3ae6e50
x29: ffff8000a3ae70a0 x28: 00000000000198d0 x27: 0000000000000000
x26: 1fffe0001f489939 x25: ffff0000fa44c9cc x24: 0000000000000001
x23: 0000000000000000 x22: 0000000000000001 x21: 0000000000000000
x20: 0000000000000200 x19: ffff0000fa44c9cc x18: dfff800000000000
x17: 00000000394bfc7d x16: ffff8000806a25ac x15: 0000000000000001
x14: 1ffff00012f50b68 x13: 0000000000000000 x12: ffff0000f1bfc2f8
x11: ffff0000f1bfc2f0 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : ffff0000c42cdb80 x7 : ffff800080592830 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff80008059283c
x2 : 0000000000000000 x1 : 0000000000000200 x0 : 0000000000000000
Call trace:
 __sanitizer_cov_trace_const_cmp4+0x8/0xa0 kernel/kcov.c:313 (P)
 dequeue_skb net/sched/sch_generic.c:293 [inline]
 qdisc_restart net/sched/sch_generic.c:398 [inline]
 __qdisc_run+0x1e0/0x2378 net/sched/sch_generic.c:416
 __dev_xmit_skb net/core/dev.c:4111 [inline]
 __dev_queue_xmit+0xd58/0x35b4 net/core/dev.c:4618
 dev_queue_xmit include/linux/netdevice.h:3313 [inline]
 neigh_hh_output include/net/neighbour.h:523 [inline]
 neigh_output include/net/neighbour.h:537 [inline]
 ip6_finish_output2+0x1614/0x20f8 net/ipv6/ip6_output.c:141
 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
 ip6_finish_output+0x428/0x7c4 net/ipv6/ip6_output.c:226
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip6_output+0x274/0x598 net/ipv6/ip6_output.c:247
 dst_output include/net/dst.h:459 [inline]
 ip6_local_out+0x120/0x160 net/ipv6/output_core.c:155
 ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline]
 udp_tunnel6_xmit_skb+0x4e8/0xa04 net/ipv6/ip6_udp_tunnel.c:111
 send6+0x578/0x940 drivers/net/wireguard/socket.c:152
 wg_socket_send_skb_to_peer+0xfc/0x1a8 drivers/net/wireguard/socket.c:178
 wg_packet_create_data_done drivers/net/wireguard/send.c:251 [inline]
 wg_packet_tx_worker+0x1a8/0x718 drivers/net/wireguard/send.c:276
 process_one_work+0x810/0x1638 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x97c/0xeec kernel/workqueue.c:3400
 kthread+0x65c/0x7b0 kernel/kthread.c:464
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6290 Comm: kworker/0:3 Not tainted 6.14.0-rc7-syzkaller-ga2392f333575 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: wg-crypt-wg0 wg_packet_tx_worker
pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : queued_spin_lock_slowpath+0x15c/0xd04 kernel/locking/qspinlock.c:380
lr : queued_spin_lock_slowpath+0x168/0xd04 kernel/locking/qspinlock.c:380
sp : ffff8000a5367000
x29: ffff8000a53670c0 x28: 1fffe0001e37f01e x27: dfff800000000000
x26: 1ffff00014a6ce2c x25: ffff8000a5367040 x24: dfff800000000000
x23: ffff8000a5367080 x22: ffff700014a6ce08 x21: 0000000000000001
x20: 1ffff00014a6ce10 x19: ffff0000f1bf80f0 x18: 1fffe000366e7286
x17: ffff80008fd3d000 x16: ffff800080bf9360 x15: 0000000000000001
x14: 1fffe0001e37f01e x13: 0000000000000000 x12: 0000000000000000
x11: ffff60001e37f01f x10: 1fffe0001e37f01e x9 : 0000000000000000
x8 : 0000000000000001 x7 : ffff800089986c48 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80008b885908
x2 : 0000000000000000 x1 : 0000000000000001 x0 : 0000000000000001
Call trace:
 __cmpwait_case_8 arch/arm64/include/asm/cmpxchg.h:229 [inline] (P)
 __cmpwait arch/arm64/include/asm/cmpxchg.h:257 [inline] (P)
 queued_spin_lock_slowpath+0x15c/0xd04 kernel/locking/qspinlock.c:380 (P)
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x2ec/0x334 kernel/locking/spinlock_debug.c:116
 __raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline]
 _raw_spin_lock+0x50/0x60 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 __dev_xmit_skb net/core/dev.c:4078 [inline]
 __dev_queue_xmit+0xb30/0x35b4 net/core/dev.c:4618
 dev_queue_xmit include/linux/netdevice.h:3313 [inline]
 neigh_hh_output include/net/neighbour.h:523 [inline]
 neigh_output include/net/neighbour.h:537 [inline]
 ip6_finish_output2+0x1614/0x20f8 net/ipv6/ip6_output.c:141
 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
 ip6_finish_output+0x428/0x7c4 net/ipv6/ip6_output.c:226
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip6_output+0x274/0x598 net/ipv6/ip6_output.c:247
 dst_output include/net/dst.h:459 [inline]
 ip6_local_out+0x120/0x160 net/ipv6/output_core.c:155
 ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline]
 udp_tunnel6_xmit_skb+0x4e8/0xa04 net/ipv6/ip6_udp_tunnel.c:111
 send6+0x578/0x940 drivers/net/wireguard/socket.c:152
 wg_socket_send_skb_to_peer+0xfc/0x1a8 drivers/net/wireguard/socket.c:178
 wg_packet_create_data_done drivers/net/wireguard/send.c:251 [inline]
 wg_packet_tx_worker+0x1a8/0x718 drivers/net/wireguard/send.c:276
 process_one_work+0x810/0x1638 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x97c/0xeec kernel/workqueue.c:3400
 kthread+0x65c/0x7b0 kernel/kthread.c:464
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862