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

[Diego Viola]

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