Re: [PATCH] driver core: Make Kconfig text for DEBUG_TEST_DRIVER_REMOVE stronger

From: Greg Kroah-Hartman
Date: Mon Oct 31 2016 - 11:07:25 EST


On Mon, Oct 31, 2016 at 09:10:57AM -0500, Rob Herring wrote:
> On Mon, Oct 31, 2016 at 7:28 AM, Geert Uytterhoeven
> <geert@xxxxxxxxxxxxxx> wrote:
> > Hi Greg,
> >
> > On Mon, Oct 31, 2016 at 1:21 PM, Greg Kroah-Hartman
> > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >> On Mon, Oct 31, 2016 at 11:12:45AM +0100, Geert Uytterhoeven wrote:
> >>> On Fri, Oct 7, 2016 at 6:09 PM, Laura Abbott <labbott@xxxxxxxxxx> wrote:
> >>> > The current state of driver removal is not great.
> >>> > CONFIG_DEBUG_TEST_DRIVER_REMOVE finds lots of errors. The help text
> >>> > currently undersells exactly how many errors this option will find. Add
> >>> > a bit more description to indicate this option shouldn't be turned on
> >>> > unless you actually want to debug driver removal. The text can be
> >>> > changed later when more drivers are fixed up.
> >>>
> >>> Indeed, this is failing miserably for e.g. SoC clock drivers using
> >>> platform_driver_probe(), which are never retried, rendering the complete
> >>> system useless.
> >>
> >> Why are they never retried?
> >
> > Because platform_driver_probe() is meant for non-hotpluggable devices,
> > and unregisters the platform driver immediately if probe fails.
> > See also the comments for __platform_driver_probe():
>
> My patch "driver core: skip removal test for non-removable drivers"
> fixes this case. It seems to have dropped from Greg's queue, so I'll
> resend.

Odd, I don't see that anywhere here, sorry about that...