INFO: task syz.6.5073:19449 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.5073 state:D stack:27544 pid:19449 tgid:19444 ppid:8181 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5526 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7277
__schedule_loop kernel/sched/core.c:7354 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7369
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7426
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xccb/0x1bd0 kernel/locking/mutex.c:821
write_ports+0xa5/0xcc0 fs/nfsd/nfsctl.c:867
nfsctl_transaction_write+0x106/0x1a0 fs/nfsd/nfsctl.c:114
nfsctl_transaction_read+0x82/0xa0 fs/nfsd/nfsctl.c:129
vfs_read+0x1e4/0xb40 fs/read_write.c:572
ksys_read+0x12a/0x250 fs/read_write.c:716
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f82b559e159
RSP: 002b:00007f82b6459028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f82b5826090 RCX: 00007f82b559e159
RDX: 0000000000000064 RSI: 0000200000000180 RDI: 0000000000000004
RBP: 00007f82b563503b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f82b5826128 R14: 00007f82b5826090 R15: 00007ffee8973128
Showing all locks held in the system:
locks held by pr/ttyS0/16: 2, last CPU#1:
#0: ffffffff8edd87b8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
#0: ffffffff8edd87b8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline]
#0: ffffffff8edd87b8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x49/0x60 kernel/printk/printk.c:291
#1: ffffffff9bc6bc78 (&port_lock_key){-.-.}-{3:3}, at: __uart_port_lock_irqsave include/linux/serial_core.h:613 [inline]
#1: ffffffff9bc6bc78 (&port_lock_key){-.-.}-{3:3}, at: univ8250_console_device_lock+0x64/0xc0 drivers/tty/serial/8250/8250_core.c:413
locks held by khungtaskd/31: 1, last CPU#0:
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6871
locks held by kworker/1:11/6307: 3, on CPU#1:
#0: ffff88801c05b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90003847d08 (netdev_work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: netdev_work_proc+0x71/0x880 net/core/netdev_work.c:132
locks held by kworker/u8:13/10601: 4, last CPU#0:
#0: ffff88801d2d8940 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc900050dfd08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff90cb9c08 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:677
#3: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: wg_destruct+0x30/0x3f0 drivers/net/wireguard/device.c:246
locks held by kworker/u8:17/10605: 3, on CPU#0:
#0: ffff888033838940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc9000551fd08 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#2: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11f/0x1360 net/ipv6/addrconf.c:4230
locks held by getty/12838: 2, on CPU#1:
#0: ffff8880335520a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90002f0c2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
locks held by syz-executor/16372: 4, last CPU#0:
#0: ffffffff8ef3d970 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1542 [inline]
#0: ffffffff8ef3d970 (dup_mmap_sem){++++}-{0:0}, at: copy_mm kernel/fork.c:1595 [inline]
#0: ffffffff8ef3d970 (dup_mmap_sem){++++}-{0:0}, at: copy_process+0x4806/0x8370 kernel/fork.c:2310
#1: ffff888026e91d38 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff888026e91d38 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x127/0x2370 mm/mmap.c:1716
#2: ffff88807c44a9f8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff88807c44a9f8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x1c9/0x2370 mm/mmap.c:1723
#3: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290
locks held by syz.6.5073/19445: 3, on CPU#1:
#0: ffff8880283ecef0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259
#1: ffff8880756f6460 (sb_writers#24){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739
#2: ffffffff8f289500 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xa5/0xcc0 fs/nfsd/nfsctl.c:867
locks held by syz.6.5073/19449: 2, on CPU#0:
#0: ffff88807daa7430 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259
#1: ffffffff8f289500 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xa5/0xcc0 fs/nfsd/nfsctl.c:867
locks held by kworker/u8:47/21124: 2, on CPU#0:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc9000367fd08 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by kworker/u8:48/21125: 6, last CPU#0:
#0: ffff88802bf94940 ((wq_completion)krds_cp_wq#11/0){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc9000366fd08 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffff88807dac8680 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1da/0xaa0 net/rds/tcp_connect.c:118
#3: ffff8880739bd060 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#3: ffff8880739bd060 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: inet_stream_connect+0x43/0xa0 net/ipv4/af_inet.c:754
#4: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#4: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#4: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: ip_route_output_key_hash+0xd6/0x2b0 net/ipv4/route.c:2733
#5: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#5: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#5: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#5: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by syz.2.6187/23076: 3, last CPU#0:
#0: ffff888053246460 (sb_writers#6){.+.+}-{0:0}, at: get_signal+0x1f2a/0x21e0 kernel/signal.c:3036
#1: ffff8880539bb2c8 (&sb->s_type->i_mutex_key#15){++++}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#1: ffff8880539bb2c8 (&sb->s_type->i_mutex_key#15){++++}-{4:4}, at: shmem_file_write_iter+0x86/0x140 mm/shmem.c:3430
#2: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#2: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#2: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: avc_has_perm_noaudit+0x56/0x3b0 security/selinux/avc.c:1155
locks held by syz.9.6190/23083: 1, on CPU#1:
#0: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x371/0xe90 net/core/rtnetlink.c:7143
locks held by syz.2.6191/23088: 1, on CPU#0:
#0: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
#0: ffffffff90cd2700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xac3/0x2620 net/core/rtnetlink.c:4219
locks held by dhcpcd-run-hook/23085: 1, last CPU#1:
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by modprobe/23090: 1, last CPU#0:
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: path_init+0xac1/0x1ab0 fs/namei.c:2689
locks held by syz.1.6193/23091: 1, last CPU#0:
#0: ffff8880715816c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(lazy)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16 Comm: pr/ttyS0 Tainted: G L syzkaller #0 PREEMPT(lazy)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
RIP: 0010:__ptr_ring_check_produce include/linux/ptr_ring.h:113 [inline]
RIP: 0010:__ptr_ring_produce include/linux/ptr_ring.h:126 [inline]
RIP: 0010:ptr_ring_produce_bh include/linux/ptr_ring.h:185 [inline]
RIP: 0010:wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:169 [inline]
RIP: 0010:wg_packet_create_data drivers/net/wireguard/send.c:320 [inline]
RIP: 0010:wg_packet_send_staged_packets+0xf29/0x1640 drivers/net/wireguard/send.c:388
Code: 01 84 c0 74 08 3c 03 0f 8e 0a 07 00 00 48 63 43 40 48 8d 04 c2 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 80 3c 11 00 <0f> 85 cc 06 00 00 48 83 38 00 0f 85 93 03 00 00 e8 62 e4 30 fb 48
RSP: 0018:ffffc90000a181f0 EFLAGS: 00000246
RAX: ffff8880404d4508 RBX: ffff88803375cec0 RCX: 1ffff1100809a8a1
RDX: dffffc0000000000 RSI: ffffffff86db3827 RDI: ffff88803375d008
RBP: ffffc90000a18320 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000400 R11: 0000000000000001 R12: ffff8880441eb640
R13: 0000000000000001 R14: ffff88803375d000 R15: ffff88802a4ea7a0
FS: 0000000000000000(0000) GS:ffff888123c59000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7aaddf6d58 CR3: 0000000073a22000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000460
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
wg_xmit+0x8a0/0x11a0 drivers/net/wireguard/device.c:218
__netdev_start_xmit include/linux/netdevice.h:5429 [inline]
netdev_start_xmit include/linux/netdevice.h:5438 [inline]
xmit_one net/core/dev.c:3937 [inline]
dev_hard_start_xmit+0x121/0x760 net/core/dev.c:3953
__dev_queue_xmit+0x1bbf/0x4970 net/core/dev.c:4926
dev_queue_xmit include/linux/netdevice.h:3461 [inline]
neigh_connected_output+0x3b7/0x5d0 net/core/neighbour.c:1645
neigh_output include/net/neighbour.h:560 [inline]
ip6_finish_output2+0xb0e/0x1d50 net/ipv6/ip6_output.c:138
__ip6_finish_output+0x357/0xdf0 net/ipv6/ip6_output.c:210
ip6_finish_output net/ipv6/ip6_output.c:221 [inline]
NF_HOOK_COND include/linux/netfilter.h:314 [inline]
ip6_output+0x2aa/0xa60 net/ipv6/ip6_output.c:248
dst_output include/net/dst.h:470 [inline]
NF_HOOK include/linux/netfilter.h:325 [inline]
ndisc_send_skb+0xa85/0x1bf0 net/ipv6/ndisc.c:513
ndisc_send_rs+0x129/0x680 net/ipv6/ndisc.c:724
addrconf_rs_timer+0x424/0x880 net/ipv6/addrconf.c:4073
call_timer_fn+0x198/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers+0x757/0xb00 kernel/time/timer.c:2374
__run_timer_base kernel/time/timer.c:2386 [inline]
__run_timer_base kernel/time/timer.c:2378 [inline]
run_timer_base+0x114/0x190 kernel/time/timer.c:2395
run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2405
handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:221
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 b6 79 13 f6 48 89 df e8 3e d0 13 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 95 c6 02 f6 65 48 83 3d 74 94 b8 08 00 74 16 5b
RSP: 0018:ffffc90000157ca8 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff9bc6bc60 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff8e38ba9b RDI: ffffffff8c622e80
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 205d343830333254 R12: 1ffff9200002af98
R13: ffffffff8fbd7300 R14: 0000000000000001 R15: 0000000000000001
nbcon_emit_one+0x15c/0x2b0 kernel/printk/nbcon.c:1165
nbcon_kthread_func+0x613/0x7d0 kernel/printk/nbcon.c:1271
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245