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

[Maarten Maathuis]

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.