INFO: task syz.1.1631:12435 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1631 state:D stack:26760 pid:12435 tgid:12434 ppid:5812 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x818/0x1060 kernel/locking/mutex.c:760
nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1590
genl_family_rcv_msg_doit+0x209/0x2f0 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2630
___sys_sendmsg+0x134/0x1d0 net/socket.c:2684
__sys_sendmsg+0x16d/0x220 net/socket.c:2716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f538cf8f749
RSP: 002b:00007f538de2e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f538d1e5fa0 RCX: 00007f538cf8f749
RDX: 0000000000008004 RSI: 0000200000000180 RDI: 000000000000000a
RBP: 00007f538d013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f538d1e6038 R14: 00007f538d1e5fa0 R15: 00007ffe130ae618
Showing all locks held in the system:
1 lock held by rcu_exp_gp_kthr/18:
#0: ffff8880b843a398 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:646 [inline]
#0: ffff8880b843a398 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:631
5 locks held by kworker/1:0/24:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c4760 (rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:4/77:
#0:
ffff88813ff29148
(
(wq_completion)events_unbound
){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
#1: ffffc9000216fd00 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
#2: ffff888022f50788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6358 [inline]
#2: ffff888022f50788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0x99/0x580 net/wireless/core.c:421
2 locks held by getty/5570:
#0: ffff88803560f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
4 locks held by kworker/u8:3/11690:
#0: ffff8880b843a398 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:646 [inline]
#0: ffff8880b843a398 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:631
#1: ffff8880b8524088 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:220 [inline]
#1: ffff8880b8524088 (psi_seq){-.-.}-{0:0}, at: __schedule+0x1861/0x5de0 kernel/sched/core.c:6923
#2: ffff8880564c7250 (&devlink->lock_key#4){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x56/0xcf0 drivers/net/netdevsim/dev.c:853
#3: ffffffff9ad21038 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x14c/0x4c0 lib/debugobjects.c:818
3 locks held by kworker/0:0/12270:
#0: ffff88813ff11948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
#1: ffffc90005a4fd00 (binder_deferred_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
#2: ffffffff8e3cfcf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by syz.2.1629/12432:
#0: ffffffff9018bad0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ee2a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
2 locks held by syz.1.1631/12435:
#0: ffffffff9018bad0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ee2a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1590
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf3f/0x1170 kernel/hung_task.c:495
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12270 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:401
Code: 65 93 fc 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 cc cc cc cc e8 e8 06 fc fc eb a2 e8 71 07
RSP: 0018:ffffc90005a4f2f8 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff852982d0 RDI: ffffffff9addb780
RBP: ffffffff9addb740 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff35bb742 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888124a05000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3740d1 CR3: 0000000080a67000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:137 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
wait_for_lsr+0x13a/0x210 drivers/tty/serial/8250/8250_port.c:1961
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0xf81/0x1890 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3111 [inline]
console_flush_all+0x801/0xc60 kernel/printk/printk.c:3199
__console_flush_and_unlock kernel/printk/printk.c:3258 [inline]
console_unlock+0xd8/0x210 kernel/printk/printk.c:3298
vprintk_emit+0x3d7/0x680 kernel/printk/printk.c:2423
dev_vprintk_emit drivers/base/core.c:4914 [inline]
dev_printk_emit+0xfa/0x140 drivers/base/core.c:4925
__dev_printk+0xf5/0x270 drivers/base/core.c:4937
_dev_info+0xe4/0x120 drivers/base/core.c:4983
usb_disconnect+0xec/0x9c0 drivers/usb/core/hub.c:2326
hub_port_connect drivers/usb/core/hub.c:5406 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x1c81/0x4fe0 drivers/usb/core/hub.c:5952
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263
process_scheduled_works kernel/workqueue.c:3346 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245