Re: How to debug DEBUG_TEST_DRIVER_REMOVE hang during loading of kernel?

From: Maarten Maathuis
Date: Fri Nov 04 2016 - 16:47:16 EST


Anyone have advice where else I can ask?

On Sat, Oct 29, 2016 at 1:07 PM, Maarten Maathuis <madman2003@xxxxxxxxx> wrote:
> Anyone have suggestions?
>
> On Thu, Oct 27, 2016 at 8:42 PM, Maarten Maathuis <madman2003@xxxxxxxxx> wrote:
>> Hi,
>>
>> I recently had trouble with loading a 4.9rcX kernel, which was hanging
>> after loading the initial kernel ramdisk. After some painful bisecting
>> I found this:
>>
>> bea5b158ff0da9c7246ff391f754f5f38e34577a is the first bad commit
>> commit bea5b158ff0da9c7246ff391f754f5f38e34577a
>> Author: Rob Herring <robh@xxxxxxxxxx>
>> Date: Thu Aug 11 10:20:58 2016 -0500
>>
>> driver core: add test of driver remove calls during probe
>>
>> In recent discussions on ksummit-discuss[1], it was suggested to do a
>> sequence of probe, remove, probe for testing driver remove paths. This
>> adds a kconfig option for said test.
>>
>> [1] https://lists.linuxfoundation.org/pipermail/ksummit-discuss/2016-August/003459.html
>>
>> Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
>> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
>> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>>
>> It turns out that the package i was using to build the kernel had
>> DEBUG_TEST_DRIVER_REMOVE enabled.
>>
>> How do I actually figure out why this test causes a hang. I don't have
>> a COM port available to use as serial console, and i don't know if it
>> would even help.
>>
>> Please CC me as i'm not a member of this mailinglist.
>>
>> Maarten.
>>
>> --
>> Far away from the primal instinct, the song seems to fade away, the
>> river get wider between your thoughts and the things we do and say.
>
>
>
> --
> Far away from the primal instinct, the song seems to fade away, the
> river get wider between your thoughts and the things we do and say.



--
Far away from the primal instinct, the song seems to fade away, the
river get wider between your thoughts and the things we do and say.