INFO: task syz.8.4615:29499 blocked for more than 143 seconds.
Tainted: G U L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.4615 state:D stack:27400 pid:29499 tgid:29498 ppid:28815 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xfe4/0x5e10 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
nfsd_nl_version_set_doit+0xc4/0x7a0 fs/nfsd/nfsctl.c:1736
genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa54/0xc30 net/socket.c:2592
___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
__sys_sendmsg+0x170/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1c86f9aeb9
RSP: 002b:00007f1c87e6c028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1c87215fa0 RCX: 00007f1c86f9aeb9
RDX: 0000000000000844 RSI: 00002000000004c0 RDI: 0000000000000003
RBP: 00007f1c87008c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1c87216038 R14: 00007f1c87215fa0 R15: 00007ffd09682e38
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/1:2/942:
2 locks held by getty/5588:
#0: ffff88814cde20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:5/5898:
2 locks held by kworker/0:4/5915:
#0: ffff88813fe15948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
#1: ffffc900048afc98 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
4 locks held by kworker/u11:25/26797:
#0: ffff88801c29f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
#1: ffffc9000bf57c98 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
#2:
ffffffff903dcef0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xab/0x830 net/core/net_namespace.c:670
#3: ffffffff8e5ef8f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by syz.6.4426/28564:
#0: ffffffff904a2690 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ea472a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1596
2 locks held by syz-executor/28579:
#0: ffff8880377780e0 (&type->s_umount_key#56){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880377780e0 (&type->s_umount_key#56){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880377780e0 (&type->s_umount_key#56){++++}-{4:4}, at: deactivate_super fs/super.c:506 [inline]
#0: ffff8880377780e0 (&type->s_umount_key#56){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:503
#1: ffffffff8ea472a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz.8.4615/29499:
#0: ffffffff904a2690 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ea472a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xc4/0x7a0 fs/nfsd/nfsctl.c:1736
1 lock held by syz.5.4955/31305:
2 locks held by syz-executor/31525:
#0: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
#1: ffffffff8e5ef8f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz.9.4999/31537:
#0: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
1 lock held by syz.0.5019/31651:
#0: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
1 lock held by dhcpcd-run-hook/31772:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [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:346 [inline]
watchdog+0xcc3/0xfe0 kernel/hung_task.c:515
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:debug_object_activate+0xed/0x490 lib/debugobjects.c:853
Code: 01 00 00 00 00 49 c7 41 08 00 00 00 00 48 8b 84 24 b8 00 00 00 65 48 2b 05 c8 88 f6 0e 0f 85 49 03 00 00 48 8d 65 d8 89 d0 5b <41> 5c 41 5d 41 5e 41 5f 5d e9 c5 e8 89 06 49 89 fd e8 7d e4 ff ff
RSP: 0018:ffffc900001473f8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888067ba8678 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffffc90000147418 R08: 0000000000000000 R09: fffff52000028e6a
R10: ffffffff9b122313 R11: 0000000000000000 R12: 0000000000000002
R13: ffff888067ba8678 R14: dffffc0000000000 R15: 1ffff92000028e6a
FS: 0000000000000000(0000) GS:ffff8881245e3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff60f4dbb8 CR3: 0000000032df8000 CR4: 00000000003526f0
Call Trace:
debug_work_activate kernel/workqueue.c:664 [inline]
insert_work+0x2e/0x230 kernel/workqueue.c:2177
__queue_work+0x96f/0x10f0 kernel/workqueue.c:2335
queue_work_on+0x180/0x1e0 kernel/workqueue.c:2386
__ieee80211_queue_skb_to_iface+0x236/0x360 net/mac80211/rx.c:239
ieee80211_queue_skb_to_iface net/mac80211/rx.c:261 [inline]
ieee80211_rx_h_mgmt net/mac80211/rx.c:4157 [inline]
ieee80211_rx_handlers+0x7701/0xa740 net/mac80211/rx.c:4232
ieee80211_invoke_rx_handlers net/mac80211/rx.c:4262 [inline]
ieee80211_prepare_and_rx_handle+0x2b9f/0x7840 net/mac80211/rx.c:5132
ieee80211_rx_for_interface+0x110/0x770 net/mac80211/rx.c:5233
__ieee80211_rx_handle_packet net/mac80211/rx.c:5405 [inline]
ieee80211_rx_list+0x13d7/0x2df0 net/mac80211/rx.c:5544
ieee80211_rx_napi+0xdc/0x400 net/mac80211/rx.c:5567
ieee80211_rx include/net/mac80211.h:5216 [inline]
ieee80211_handle_queued_frames+0xc8/0x120 net/mac80211/main.c:452
tasklet_action_common+0x2de/0x3d0 kernel/softirq.c:925
handle_softirqs+0x1ea/0x910 kernel/softirq.c:622
run_ksoftirqd kernel/softirq.c:1063 [inline]
run_ksoftirqd+0x38/0x60 kernel/softirq.c:1055
smpboot_thread_fn+0x3d3/0xaa0 kernel/smpboot.c:160
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246