INFO: task syz.4.4655:23204 blocked for more than 143 seconds.
Not tainted 6.16.0-syzkaller-11743-g6bcdbd62bd56 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.4655 state:D stack:28328 pid:23204 tgid:23195 ppid:18215 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1360 kernel/locking/mutex.c:760
device_lock include/linux/device.h:911 [inline]
usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054
chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414
do_dentry_open+0x953/0x13f0 fs/open.c:965
vfs_open+0x3b/0x340 fs/open.c:1095
do_open fs/namei.c:3887 [inline]
path_openat+0x2ee5/0x3830 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_openat fs/open.c:1466 [inline]
__se_sys_openat fs/open.c:1461 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1461
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f829978d4d0
RSP: 002b:00007f82975b3b70 EFLAGS: 00000293
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f829978d4d0
RDX: 0000000000000000 RSI: 00007f82975b3c10 RDI: 00000000ffffff9c
RBP: 00007f82975b3c10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 0000000000000000 R14: 00007f82999b6160 R15: 00007f8299adfa28
Showing all locks held in the system:
3 locks held by kworker/0:0/9:
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc900000e7bc0 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900000e7bc0 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8e13f840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3815
1 lock held by khungtaskd/31:
#0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5625:
#0: ffff8880302630a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
9 locks held by kworker/0:2/14120:
2 locks held by kworker/u8:13/19578:
#0: ffff8881482ec948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff8881482ec948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000ab0fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000ab0fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
1 lock held by syz.4.4655/23204:
#0: ffff8880282be198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#0: ffff8880282be198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054
2 locks held by syz.2.5124/24883:
2 locks held by syz.0.5140/24940:
#0: ffff8880588ee0d8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100 net/netfilter/nf_tables_api.c:11456
#1: ffffffff8e13f978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e13f978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957
1 lock held by syz.0.5140/24941:
#0:
ffffffff8f527610
(
pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566
1 lock held by syz.3.5142/24946:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-syzkaller-11743-g6bcdbd62bd56 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 14120 Comm: kworker/0:2 Not tainted 6.16.0-syzkaller-11743-g6bcdbd62bd56 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 ce 3a 71 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 df a3 d4 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 ca 0a 2d 06 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc9000b536150 EFLAGS: 00000002
RAX: 1ffffffff33bcc60 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 00000000000fffff RDI: 0000000000100000
RBP: ffffffff99de6770 R08: ffff888024a88237 R09: 1ffff11004951046
R10: dffffc0000000000 R11: ffffffff854e7090 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff99de64e0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c24000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000057eff8 CR3: 000000003d224000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000008 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
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+0xd1/0x2f0 drivers/tty/serial/8250/8250_port.c:1984
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3288 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3311 [inline]
serial8250_console_write+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3396
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x728/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914
dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925
__netdev_printk+0x3d7/0x4d0 net/core/dev.c:12588
netdev_warn+0x10a/0x160 net/core/dev.c:12641
asix_read_cmd drivers/net/usb/asix_common.c:33 [inline]
asix_check_host_enable drivers/net/usb/asix_common.c:102 [inline]
__asix_mdio_read drivers/net/usb/asix_common.c:484 [inline]
asix_mdio_read+0x257/0x530 drivers/net/usb/asix_common.c:507
asix_phy_reset+0xbc/0x1b0 drivers/net/usb/asix_devices.c:215
ax88172_bind+0x3f0/0x5e0 drivers/net/usb/asix_devices.c:275
usbnet_probe+0xa93/0x2870 drivers/net/usb/usbnet.c:1781
usb_probe_interface+0x668/0xc30 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x26a/0x9e0 drivers/base/dd.c:659
__driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801
driver_probe_device+0x4f/0x430 drivers/base/dd.c:831
__device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959
bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462
__device_attach+0x2b8/0x400 drivers/base/dd.c:1031
bus_probe_device+0x185/0x260 drivers/base/bus.c:537
device_add+0x7b6/0xb50 drivers/base/core.c:3689
usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
usb_probe_device+0x1c1/0x390 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x26a/0x9e0 drivers/base/dd.c:659
__driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801
driver_probe_device+0x4f/0x430 drivers/base/dd.c:831
__device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959
bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462
__device_attach+0x2b8/0x400 drivers/base/dd.c:1031
bus_probe_device+0x185/0x260 drivers/base/bus.c:537
device_add+0x7b6/0xb50 drivers/base/core.c:3689
usb_new_device+0xa39/0x16f0 drivers/usb/core/hub.c:2694
hub_port_connect drivers/usb/core/hub.c:5566 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x2958/0x4a20 drivers/usb/core/hub.c:5952
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245