[syzbot] [kernel?] INFO: task hung in usb_disable_device (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 5d5fd841c346 Merge 7.2-rc5 into usb-next
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=14fbca9e580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6ec4d592e55f7960
dashboard link: https://syzkaller.appspot.com/bug?extid=5cf28d3643d94bfb0821
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2ed536ae4daf/disk-5d5fd841.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ab40098ccbf1/vmlinux-5d5fd841.xz
kernel image: https://storage.googleapis.com/syzbot-assets/66d5c395f47c/bzImage-5d5fd841.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5cf28d...@syzkaller.appspotmail.com

INFO: task kworker/1:1:28 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:1 state:D
stack:19176 pid:28 tgid:28 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1325/0x47d0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xccc/0x1bd0 kernel/locking/mutex.c:821
device_lock include/linux/device.h:1102 [inline]
device_del+0xa0/0x9b0 drivers/base/core.c:3923
usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2350
hub_port_connect drivers/usb/core/hub.c:5412 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5712 [inline]
port_event drivers/usb/core/hub.c:5876 [inline]
hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5958
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
INFO: task kworker/0:2:247 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2 state:D stack:20520 pid:247 tgid:247 ppid:2 task_flags:0x4288060 flags:0x00080000
Workqueue: events request_firmware_work_func
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1325/0x47d0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
lbs_wait_for_firmware_load+0x11e/0x1e0 drivers/net/wireless/marvell/libertas/firmware.c:117
lbs_remove_card+0x84/0x390 drivers/net/wireless/marvell/libertas/main.c:913
if_usb_disconnect+0xc5/0x270 drivers/net/wireless/marvell/libertas/if_usb.c:317
usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:461
device_remove drivers/base/dd.c:618 [inline]
device_remove+0x12a/0x180 drivers/base/dd.c:610
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
usb_driver_release_interface drivers/usb/core/driver.c:643 [inline]
usb_forced_unbind_intf+0x1a4/0x240 drivers/usb/core/driver.c:1137
usb_reset_device+0x411/0xaa0 drivers/usb/core/hub.c:6409
if_usb_reset_device.isra.0+0x21e/0x290 drivers/net/wireless/marvell/libertas/if_usb.c:400
if_usb_prog_firmware+0x626/0xef0 drivers/net/wireless/marvell/libertas/if_usb.c:889
lbs_fw_loaded drivers/net/wireless/marvell/libertas/firmware.c:23 [inline]
helper_firmware_cb drivers/net/wireless/marvell/libertas/firmware.c:80 [inline]
helper_firmware_cb+0x1f7/0x2d0 drivers/net/wireless/marvell/libertas/firmware.c:64
request_firmware_work_func+0x13f/0x440 drivers/base/firmware_loader/main.c:1164
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>

Showing all locks held in the system:
5 locks held by kworker/1:1/28:
#0:
ffff888106aa4540
(
(wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc900001e7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88810af571d8
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1102 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3:
ffff8881158cd1d8
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
(&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2341
#4: ffff8881158c81a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff8881158c81a0 (&dev->mutex){....}-{4:4}, at: device_del+0xa0/0x9b0 drivers/base/core.c:3923
1 lock held by khungtaskd/30:
#0: ffffffff896e2b40 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff896e2b40 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff896e2b40 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/0:2/247:
#0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1:
ffffc90001af7d18
(
(work_completion)(&fw_work->work)
){+.+.}-{0:0}
, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2:
ffff8881158c81a0
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1102 [inline]
, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369
2 locks held by getty/2918:
#0:
ffff888115d290a0
(
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1:
ffffc900000452e8
(
&ldata->atomic_read_lock
){+.+.}-{4:4}
, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
2 locks held by kworker/0:5/5267:
2 locks held by kworker/0:11/11531:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<TASK>
__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:122
nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9069 Comm: kworker/0:9 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events legacy_dvb_usb_read_remote_control
RIP: 0010:__sanitizer_cov_trace_pc+0xb/0x70 kernel/kcov.c:213
Code: 5f 00 be 03 00 00 00 5b e9 e2 72 23 01 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 8b 05 e5 9b 4a 0b <48> 8b 34 24 65 48 8b 15 c1 9b 4a 0b a9 00 01 ff 00 74 1b f6 c4 01
RSP: 0018:ffffc900125cf238 EFLAGS: 00000216
RAX: 0000000000000001 RBX: ffffffff878ae180 RCX: ffffffff87788dd0
RDX: 0000000000000063 RSI: 000000000000002a RDI: ffff88811567bc00
RBP: ffffc900125cf2e0 R08: 0000000000000001 R09: 000000000000002a
R10: 0000000000000063 R11: 0000000000b421c8 R12: 0000000000000063
R13: ffffffff878ae181 R14: ffffc900125cf370 R15: 0000000000000033
FS: 0000000000000000(0000) GS:ffff888268636000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556db20908 CR3: 00000001175ac000 CR4: 00000000003506f0
Call Trace:
<TASK>
format_decode+0x32f/0xdd0 lib/vsprintf.c:2739
vsnprintf+0x1c0/0x1300 lib/vsprintf.c:2887
snprintf+0xc7/0x100 lib/vsprintf.c:3043
print_caller kernel/printk/printk.c:1368 [inline]
info_print_prefix+0x134/0x350 kernel/printk/printk.c:1387
record_print_text+0x143/0x3c0 kernel/printk/printk.c:1434
printk_get_next_message+0x2d1/0x6c0 kernel/printk/printk.c:3072
console_emit_next_record kernel/printk/printk.c:3137 [inline]
console_flush_one_record+0x67c/0xe50 kernel/printk/printk.c:3269
console_flush_all kernel/printk/printk.c:3343 [inline]
__console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
console_unlock+0x103/0x260 kernel/printk/printk.c:3413
vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479
_printk+0xcf/0x110 kernel/printk/printk.c:2504
legacy_dvb_usb_read_remote_control.cold+0x11/0x16 drivers/media/usb/dvb-usb/dvb-usb-remote.c:124
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>


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