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

From: Diego Viola
Date: Tue Mar 21 2017 - 18:52:45 EST


On Tue, Mar 21, 2017 at 12:29 PM, Diego Viola <diego.viola@xxxxxxxxx> wrote:
> On Tue, Mar 21, 2017 at 10:04 AM, Diego Viola <diego.viola@xxxxxxxxx> wrote:
>> On Mon, Mar 20, 2017 at 8:15 PM, Diego Viola <diego.viola@xxxxxxxxx> wrote:
>>> On Mon, Mar 20, 2017 at 3:27 PM, Diego Viola <diego.viola@xxxxxxxxx> wrote:
>>>> 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
>>>
>>> ftrace_dump_on_oops is what I was looking for.
>>>
>>> Diego
>>
>> I tried ftrace_dump_on_oops but I can't see the trace coming in, not
>> sure what I'm doing wrong. :(
>>
>> Diego
>
> I was able to obtain the trace with this: hung_task_panic=1
> no_console_suspend=1 ftrace_dump_on_oops
>
> Diego

Here's the log I was able to obtain today, dmesg + ftrace at the time
of the crash:

https://bugzilla.kernel.org/attachment.cgi?id=255419

USB keyboard and mouse was plugged when I reproduced this.

Please let me know if you need more info.

Diego