INFO: task hung in hub_port_init

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: d3d45f82 Merge tag 'pinctrl-v5.9-2' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14c3b3db900000
kernel config: https://syzkaller.appspot.com/x/.config?x=89ab6a0c48f30b49
dashboard link: https://syzkaller.appspot.com/bug?extid=74d6ef051d3d2eacf428
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=153bf5bd900000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=124c92af900000

The issue was bisected to:

commit 6dcf45e514974a1ff10755015b5e06746a033e5f
Author: Niklas Söderlund <niklas.soder...@ragnatech.se>
Date: Mon Jan 9 15:34:04 2017 +0000

sh_eth: use correct name for ECMR_MPDE bit

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=152bb760500000
final oops: https://syzkaller.appspot.com/x/report.txt?x=172bb760500000
console output: https://syzkaller.appspot.com/x/log.txt?x=132bb760500000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+74d6ef...@syzkaller.appspotmail.com
Fixes: 6dcf45e51497 ("sh_eth: use correct name for ECMR_MPDE bit")

INFO: task kworker/0:0:5 blocked for more than 143 seconds.
Not tainted 5.9.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:0 state:D stack:27664 pid: 5 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
usb_kill_urb.part.0+0x197/0x220 drivers/usb/core/urb.c:696
usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:691
usb_start_wait_urb+0x24a/0x2b0 drivers/usb/core/message.c:64
usb_internal_control_msg drivers/usb/core/message.c:102 [inline]
usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:153
hub_port_init+0x11ae/0x2d80 drivers/usb/core/hub.c:4689
hub_port_connect drivers/usb/core/hub.c:5140 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x1e64/0x3e60 drivers/usb/core/hub.c:5576
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
process_scheduled_works kernel/workqueue.c:2331 [inline]
worker_thread+0x82b/0x1120 kernel/workqueue.c:2417
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task kworker/1:2:2641 blocked for more than 144 seconds.
Not tainted 5.9.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:2 state:D stack:26992 pid: 2641 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
usb_kill_urb.part.0+0x197/0x220 drivers/usb/core/urb.c:696
usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:691
usb_start_wait_urb+0x24a/0x2b0 drivers/usb/core/message.c:64
usb_internal_control_msg drivers/usb/core/message.c:102 [inline]
usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:153
usb_get_descriptor+0xc5/0x1b0 drivers/usb/core/message.c:655
usb_get_device_descriptor+0x81/0xf0 drivers/usb/core/message.c:927
hub_port_init+0x78f/0x2d80 drivers/usb/core/hub.c:4784
hub_port_connect drivers/usb/core/hub.c:5140 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x1e64/0x3e60 drivers/usb/core/hub.c:5576
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task kworker/1:1:6862 blocked for more than 146 seconds.
Not tainted 5.9.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:1 state:D stack:26864 pid: 6862 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
usb_kill_urb.part.0+0x197/0x220 drivers/usb/core/urb.c:696
usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:691
usb_start_wait_urb+0x24a/0x2b0 drivers/usb/core/message.c:64
usb_internal_control_msg drivers/usb/core/message.c:102 [inline]
usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:153
hub_port_init+0x11ae/0x2d80 drivers/usb/core/hub.c:4689
hub_port_connect drivers/usb/core/hub.c:5140 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x1e64/0x3e60 drivers/usb/core/hub.c:5576
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task kworker/0:1:6870 blocked for more than 148 seconds.
Not tainted 5.9.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1 state:D stack:27416 pid: 6870 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
usb_kill_urb.part.0+0x197/0x220 drivers/usb/core/urb.c:696
usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:691
usb_start_wait_urb+0x24a/0x2b0 drivers/usb/core/message.c:64
usb_internal_control_msg drivers/usb/core/message.c:102 [inline]
usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:153
usb_get_descriptor+0xc5/0x1b0 drivers/usb/core/message.c:655
usb_get_device_descriptor+0x81/0xf0 drivers/usb/core/message.c:927
hub_port_init+0x78f/0x2d80 drivers/usb/core/hub.c:4784
hub_port_connect drivers/usb/core/hub.c:5140 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x1e64/0x3e60 drivers/usb/core/hub.c:5576
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task kworker/1:3:6898 blocked for more than 150 seconds.
Not tainted 5.9.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:3 state:D stack:27256 pid: 6898 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
usb_kill_urb.part.0+0x197/0x220 drivers/usb/core/urb.c:696
usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:691
usb_start_wait_urb+0x24a/0x2b0 drivers/usb/core/message.c:64
usb_internal_control_msg drivers/usb/core/message.c:102 [inline]
usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:153
usb_get_descriptor+0xc5/0x1b0 drivers/usb/core/message.c:655
usb_get_device_descriptor+0x81/0xf0 drivers/usb/core/message.c:927
hub_port_init+0x78f/0x2d80 drivers/usb/core/hub.c:4784
hub_port_connect drivers/usb/core/hub.c:5140 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x1e64/0x3e60 drivers/usb/core/hub.c:5576
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Showing all locks held in the system:
5 locks held by kworker/0:0/5:
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
#1: ffffc90000cbfda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
#2: ffff88809e17a218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:785 [inline]
#2: ffff88809e17a218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1b6/0x3e60 drivers/usb/core/hub.c:5522
#3: ffff88809e163588 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3012 [inline]
#3: ffff88809e163588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5139 [inline]
#3: ffff88809e163588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
#3: ffff88809e163588 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5494 [inline]
#3: ffff88809e163588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x1e4f/0x3e60 drivers/usb/core/hub.c:5576
#4: ffff888217aea068 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_init+0x1b6/0x2d80 drivers/usb/core/hub.c:4563
2 locks held by kworker/u4:4/208:
1 lock held by khungtaskd/1167:
#0: ffffffff8a067f40 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5852
5 locks held by kworker/1:2/2641:
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
#1: ffffc90008de7da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
#2: ffff88809e5de218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:785 [inline]
#2: ffff88809e5de218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1b6/0x3e60 drivers/usb/core/hub.c:5522
#3: ffff88809e594588 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3012 [inline]
#3: ffff88809e594588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5139 [inline]
#3: ffff88809e594588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
#3: ffff88809e594588 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5494 [inline]
#3: ffff88809e594588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x1e4f/0x3e60 drivers/usb/core/hub.c:5576
#4: ffff888217ba0c68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_init+0x1b6/0x2d80 drivers/usb/core/hub.c:4563
1 lock held by in:imklog/6751:
#0: ffff8880a25dc3f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930
5 locks held by kworker/1:1/6862:
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
#0: ffff8880a62d8538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
#1: ffffc900056b7da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
#2: ffff88809e2f5218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:785 [inline]
#2: ffff88809e2f5218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1b6/0x3e60 drivers/usb/core/hub.c:5522
#3: ffff888217ac8588 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3012 [inline]
#3: ffff888217ac8588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5139 [inline]
#3: ffff888217ac8588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
#3: ffff888217ac8588 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5494 [inline]
#3: ffff888217ac8588 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x1e4f/0x3e60 drivers/usb/core/hub.c:5576
#4: ffff888217a6c268 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_init+0x1b6/0x2d80 drivers/usb/core/hub.c:4563
5 locks held by kworker/0:1/6870:


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

[Oliver Neukum]

Am Dienstag, den 06.10.2020, 01:19 -0700 schrieb syzbot:

Hi,

> HEAD commit: d3d45f82 Merge tag 'pinctrl-v5.9-2' of git://git.kernel.or..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=14c3b3db900000
> kernel config: https://syzkaller.appspot.com/x/.config?x=89ab6a0c48f30b49
> dashboard link: https://syzkaller.appspot.com/bug?extid=74d6ef051d3d2eacf428
> compiler: gcc (GCC) 10.1.0-syz 20200507
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=153bf5bd900000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=124c92af900000
>
> The issue was bisected to:
>
> commit 6dcf45e514974a1ff10755015b5e06746a033e5f
> Author: Niklas Söderlund <niklas.soder...@ragnatech.se>
> Date: Mon Jan 9 15:34:04 2017 +0000
>
> sh_eth: use correct name for ECMR_MPDE bit

I am afraid this has bisected a race condition into neverland.

> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=152bb760500000
> final oops: https://syzkaller.appspot.com/x/report.txt?x=172bb760500000
> console output: https://syzkaller.appspot.com/x/log.txt?x=132bb760500000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+74d6ef...@syzkaller.appspotmail.com
> Fixes: 6dcf45e51497 ("sh_eth: use correct name for ECMR_MPDE bit")
>
> INFO: task kworker/0:0:5 blocked for more than 143 seconds.
> Not tainted 5.9.0-rc7-syzkaller #0
> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> task:kworker/0:0 state:D stack:27664 pid: 5 ppid: 2 flags:0x00004000
> Workqueue: usb_hub_wq hub_event
> Call Trace:
> context_switch kernel/sched/core.c:3778 [inline]
> __schedule+0xec9/0x2280 kernel/sched/core.c:4527
> schedule+0xd0/0x2a0 kernel/sched/core.c:4602

By this time urb_dequeue() has been killed and has returned.

> usb_kill_urb.part.0+0x197/0x220 drivers/usb/core/urb.c:696
> usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:691
> usb_start_wait_urb+0x24a/0x2b0 drivers/usb/core/message.c:64
> usb_internal_control_msg drivers/usb/core/message.c:102 [inline]
> usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:153
> hub_port_init+0x11ae/0x2d80 drivers/usb/core/hub.c:4689
> hub_port_connect drivers/usb/core/hub.c:5140 [inline]
> hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
> port_event drivers/usb/core/hub.c:5494 [inline]
>

This looks like it should.

Which HC driver are you using for these tests? It looks like
the HCD is not acting on urb_dequeue(), rather than a locking
issue.

Regards
Oliver

[Andrey Konovalov]

Hi Oliver,

This is the USB/IP one, based on what I see in the reproducer.

Thanks!