INFO: task kworker/0:0:9 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:0 state:D stack:19752 pid:9 tgid:9 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
i2c_del_adapter+0x581/0x6e0 drivers/i2c/i2c-core-base.c:1814
dvb_usbv2_probe+0x4ae/0x41a0 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:993
usb_probe_interface+0x668/0xc30 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x26d/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+0x1c4/0x390 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x26d/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:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
5 locks held by kworker/0:0/9:
#0: ffff88823be1c148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88823be1c148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc900000e7ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc900000e7ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffff888027c2b198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#2: ffff888027c2b198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898
#3: ffff88807afd1198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#3: ffff88807afd1198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006
#4: ffff888029782160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#4: ffff888029782160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006
1 lock held by khungtaskd/31:
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:9/3548:
2 locks held by getty/5591:
#0: ffff8880238080a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036be2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by udevd/10773:
#0: ffff8880620c7790 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:182
#1: ffff88805d831c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
#2: ffff88805c057e18 (kn->active#24){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88805c057e18 (kn->active#24){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
#3: ffff88807afd1198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline]
#3: ffff88807afd1198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 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: 3548 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: iou_exit io_ring_exit_work
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:55 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline]
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
RIP: 0010:unwind_next_frame+0xad6/0x2390 arch/x86/kernel/unwind_orc.c:585
Code: 00 00 83 fe 02 0f 85 a1 07 00 00 4c 89 7c 24 28 4d 8d 7e 08 4c 89 fd 48 c1 ed 03 48 b8 00 00 00 00 00 fc ff df 80 7c 05 00 00 <74> 08 4c 89 ff e8 00 25 b2 00 4c 89 7c 24 60 48 89 5c 24 78 4d 8b
RSP: 0018:ffffc9000b7d7258 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffffffff9004e541 RCX: ffffffff8f8c727c
RDX: ffffffff9004e53c RSI: 0000000000000002 RDI: ffffffff8bbf0700
RBP: 1ffff920016fae66 R08: 0000000000000001 R09: ffffffff81738d25
R10: ffffc9000b7d7378 R11: ffffffff81ac2f50 R12: ffffc9000b7d7a60
R13: ffffc9000b7d7378 R14: ffffc9000b7d7328 R15: ffffc9000b7d7330
FS: 0000000000000000(0000) GS:ffff88812623b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f740a068 CR3: 000000007530a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559
__call_rcu_common kernel/rcu/tree.c:3123 [inline]
call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243
slab_free_hook mm/slub.c:2503 [inline]
slab_free mm/slub.c:6634 [inline]
kmem_cache_free+0x4b5/0x690 mm/slub.c:6744
__io_req_caches_free+0x1c1/0x270 io_uring/io_uring.c:2824
io_req_caches_free+0x21/0x60 io_uring/io_uring.c:2836
io_ring_exit_work+0x415/0x930 io_uring/io_uring.c:3034
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245