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

[Diego Viola]

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