Re: Dell Inspiron 5558/0VNM2T hangs at resume from suspend when USB 3 is enabled

From: Diego Viola
Date: Mon Mar 20 2017 - 14:28:21 EST


On Mon, Mar 20, 2017 at 1:32 PM, Mathias Nyman
<mathias.nyman@xxxxxxxxxxxxxxx> wrote:
> On 20.03.2017 17:39, Diego Viola wrote:
>>
>> On Mon, Mar 20, 2017 at 11:21 AM, Mathias Nyman
>> <mathias.nyman@xxxxxxxxxxxxxxx> wrote:
>>>
>>> On 19.03.2017 23:29, Diego Viola wrote:
>>>>
>>>>
>
>>>>> Still a problem with 4.11.0-rc2-ARCH+
>>>
>>> 4.11-rc2 has better xhci tracing, it shows each URB enqueue and dequeue
>>> and
>>> giveback.
>>>
>>> Could you try enabling xhci tracing before suspending (not the same as
>>> xhci
>>> verbose dynamic debug)
>>> It will generate a lot of data, so better to remove all extra USB
>>> devices.
>>>
>>> xhci tracing can be added with:
>>>
>>> mount -t debugfs none /sys/kernel/debug
>>> echo xhci-hcd >> /sys/kernel/debug/tracing/set_event
>>>
>>> and then send the output of cat /sys/kernel/debug/tracing/trace
>>
>>
>> https://bugzilla.kernel.org/attachment.cgi?id=255367
>>
>> This is with Linux 4.11.0-rc3-ARCH.
>>
>> USB mouse/keyboard was unplugged before booting the machine.
>>
>> I didn't do a suspend/resume before getting this trace, should I do that?
>>
>> Should I reproduce the hang and get a netconsole dmesg capture with
>> tracing enabled?
>
>
> A trace and a dmesg of the same suspend/reusume hang would be great.

I can capture the dmesg with netconsole once the machine hangs, but
I'm not sure how I could capture /sys/kernel/debug/tracing/trace after
the hang. I'm unable to use ssh after the hang.

> And if you can then one of a succesful suspend/resume for reference.

Here's the trace after a successful suspend/resume:

https://bugzilla.kernel.org/attachment.cgi?id=255369

>
> (I haven't yet checked the one you added to bugzilla)
>
> -Mathias

Diego