INFO: task syz.3.3706:19655 blocked for more than 143 seconds.
Not tainted 6.14.0-rc4-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.3706 state:D stack:27112 pid:19655 tgid:19650 ppid:16596 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x18bc/0x4c40 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6857
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
__mutex_lock_common kernel/locking/mutex.c:662 [inline]
__mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730
blk_trace_startstop+0xa4/0x740 kernel/trace/blktrace.c:700
blk_trace_ioctl+0x19b/0x830 kernel/trace/blktrace.c:742
blkdev_common_ioctl+0xe6c/0x2460 block/ioctl.c:622
blkdev_ioctl+0x51d/0x6f0 block/ioctl.c:687
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa70c78d169
RSP: 002b:00007fa70d50a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa70c9a6080 RCX: 00007fa70c78d169
RDX: 0000000000000000 RSI: 0000000000001274 RDI: 0000000000000004
RBP: 00007fa70c80e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fa70c9a6080 R15: 00007fff501c7788
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
2 locks held by getty/5584:
#0: ffff8880316150a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211
3 locks held by kworker/u9:1/13588:
#0: ffff88803492a948 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88803492a948 ((wq_completion)hci5){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317
#1: ffffc9000c377c60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000c377c60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317
#2: ffff88807a194d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:331
7 locks held by kworker/0:7/19342:
#0: ffff888144ebe548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888144ebe548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317
#1: ffffc900057dfc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900057dfc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317
#2: ffff8880b862d1a8 (lock#5){..-.}-{3:3}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
#2: ffff8880b862d1a8 (lock#5){..-.}-{3:3}, at: kcov_remote_stop+0x78/0x6f0 kernel/kcov.c:1007
#3: ffffffff9a83c888 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x17f/0x580 lib/debugobjects.c:818
#4: ffff888028a9a098 (&hub->status_mutex){+.+.}-{4:4}, at: hub_ext_port_status+0x57/0x840 drivers/usb/core/hub.c:621
#5: ffffffff9a8ad7d8 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed lib/debugobjects.c:1088 [inline]
#5: ffffffff9a8ad7d8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_check_no_obj_freed+0x234/0x580 lib/debugobjects.c:1129
#6: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#6: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#6: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: __queue_work+0x199/0xf50 kernel/workqueue.c:2259
4 locks held by syz.3.3706/19652:
1 lock held by syz.3.3706/19655:
#0: ffff888025763fa8 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_startstop+0xa4/0x740 kernel/trace/blktrace.c:700
5 locks held by kworker/1:1/20320:
#0: ffff888144ebe548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888144ebe548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317
#1: ffffc9000cce7c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000cce7c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317
#2: ffff888028938190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline]
#2: ffff888028938190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5861
#3: ffff8880692d5190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline]
#3: ffff8880692d5190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005
#4: ffff888011c15160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline]
#4: ffff888011c15160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005
3 locks held by syz.0.4025/20826:
#0: ffff8880b863e7d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:606
#1: ffff8880b8728948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41d/0x7a0 kernel/sched/psi.c:987
#2: ffff88802ccfb638 (&sig->wait_chldexit){....}-{3:3}, at: __wake_up_common_lock+0x25/0x1e0 kernel/sched/wait.c:105
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20320 Comm: kworker/1:1 Not tainted 6.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_in+0x76/0xb0 drivers/tty/serial/8250/8250_port.c:409
Code: d0 bd 45 fc 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 e1 70 aa fc 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c
RSP: 0018:ffffc9000cce62f8 EFLAGS: 00000006
RAX: 1ffffffff352bb05 RBX: ffffffff9a95de60 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 00000000000fffff RDI: 0000000000100000
RBP: 0000000000000000 R08: ffffffff857bffc6 R09: fffff5200199cc40
R10: dffffc0000000000 R11: ffffffff857bff80 R12: 0000000000000000
R13: dffffc0000000000 R14: 00000000000003f9 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe01ccf9fe0 CR3: 00000000237e2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 00000000ffff000b DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
serial_port_in include/linux/serial_core.h:791 [inline]
serial8250_console_write+0x4be/0x1e00 drivers/tty/serial/8250/8250_port.c:3429
console_emit_next_record kernel/printk/printk.c:3122 [inline]
console_flush_all+0x869/0xeb0 kernel/printk/printk.c:3210
__console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309
vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432
dev_vprintk_emit+0x341/0x400 drivers/base/core.c:4890
dev_printk_emit+0xdd/0x120 drivers/base/core.c:4901
_dev_info+0x122/0x170 drivers/base/core.c:4959
usb_serial_probe+0xa03/0x3060 drivers/usb/serial/usb-serial.c:1049
usb_probe_interface+0x641/0xbb0 drivers/usb/core/driver.c:396
really_probe+0x2b9/0xad0 drivers/base/dd.c:658
__driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800
driver_probe_device+0x50/0x430 drivers/base/dd.c:830
__device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958
bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462
__device_attach+0x333/0x520 drivers/base/dd.c:1030
bus_probe_device+0x189/0x260 drivers/base/bus.c:537
device_add+0x856/0xbf0 drivers/base/core.c:3665
usb_set_configuration+0x1976/0x1fb0 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0x88/0x140 drivers/usb/core/generic.c:250
usb_probe_device+0x1b8/0x380 drivers/usb/core/driver.c:291
really_probe+0x2b9/0xad0 drivers/base/dd.c:658
__driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800
driver_probe_device+0x50/0x430 drivers/base/dd.c:830
__device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958
bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462
__device_attach+0x333/0x520 drivers/base/dd.c:1030
bus_probe_device+0x189/0x260 drivers/base/bus.c:537
device_add+0x856/0xbf0 drivers/base/core.c:3665
usb_new_device+0x104a/0x19a0 drivers/usb/core/hub.c:2663
hub_port_connect drivers/usb/core/hub.c:5533 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5673 [inline]
port_event drivers/usb/core/hub.c:5833 [inline]
hub_event+0x2d6d/0x5150 drivers/usb/core/hub.c:5915
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317
worker_thread+0x870/0xd30 kernel/workqueue.c:3398
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244