Re: [PATCH 8/8] driver-core: allow enabling async probing for all modules and builtins

Dmitry Torokhov
2015-05-20T16:45:08Z

On Wed, May 20, 2015 at 12:27:34AM -0700, Greg Kroah-Hartman wrote:
> On Mon, Mar 30, 2015 at 04:20:10PM -0700, Dmitry Torokhov wrote:
> > From: "Luis R. Rodriguez" <mcgrof@suse.com>
> >
> > Folks wishing to test enabling async probe for all built-in drivers
> > and/or for all modules can use
> > __DEBUG__kernel_force_builtin_async_probe or
> > __DEBUG__kernel_force_modules_async_probe kernel parameters.
> >
> > Activating either one will taint your kernel.
> >
> > Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
> > [Dmitry: split off from another patch, split into 2 parameters, moved
> > over to core_param_unsafe()]
> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
>
> I've dropped this from my tree as I don't want to add these options,
> only to have to remove them later on when it's found out that these were
> a bad idea.

OK.

>
> I don't want to create a user api that we have to keep around for
> forever, and this would be such a thing (specifying how the kernel
> probing works.)

Given that they are marked as __DEBUG and taint the kernel I do not
believe they shoudl be considered as an API/ABI. We can emphasise this
in docs and/or kernel messages.

> For debugging, can't you just patch up your kernel and

I can, but I do not have all hardware in my possession to validate the
behavior.

> test this out? What's the real use of this? Who do you want to enable
> these? And why? What will you do with the information?

The expectation was that distribution developers might use these
switches when evaluating whether they are ready to switch to
asynchronous probing.

Thanks.

--
Dmitry