Re: [PATCH 1/2] pwm: lpss: Move namespace import into a header

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Tue, Dec 03, 2024 at 10:32:17PM +0100, Uwe Kleine-König wrote:
> On Tue, Dec 03, 2024 at 09:12:36PM +0200, Andy Shevchenko wrote:
> > On Tue, Dec 03, 2024 at 06:16:14PM +0100, Uwe Kleine-König wrote:
> > > Each user of the exported symbols related to the pwm-lpss driver needs
> > > to import the matching namespace. So this can just be done in the header
> > > together with the prototypes.
> > > 
> > > This fixes drivers/pinctrl/intel/pinctrl-intel.c which failed to import
> > > that namespace before. (However this didn't hurt because the pwm-lpss
> > > module namespace isn't used; see the next commit.)
> > 
> > I disagree on this change, I think it had been discussed already.
> 
> Who discussed this? If I was involved, I don't remember. So if you have
> a link, that would be great.

Sure, https://lore.kernel.org/linux-pwm/20220908135658.64463-1-andriy.shevchenko@linux.intel.com/
you were a participant there.

> > The header must not provide any module importing features as it effectively
> > diminishes the point of namespace. Any (ab)user can include just a header and
> > be okay with that.
> 
> Huh? Any abuser can also just do the IMPORT_NS statement? Module
> namespaces are not a safeguard against bad code? So I don't see why
> making it simple for the regular users should be the wrong choice.
> 
> Actually I think this is very elegant because this way all needs to use
> these symbols (i.e. prototype and namespace) are in a single place and
> users just do the #include and get all the preconditions.

Recent LWN https://lwn.net/Articles/998221/ article describes in more details
what I implied under abuser here.

> > Besides that, you should have based this on recent changes in the NS area of
> > the module symbols, i.e. module namespaces needs to be provided as string
> > literals.
> 
> I coordinated my patch set with the pwm maintainer and he is ok with it
> :-) That's why I wrote "This conflicts with
> ceb8bf2ceaa77fe222fe8fe32cb7789c9099ddf1 that is currently in Linus'
> tree. I'll take care about that." in the cover letter.

Other subsystems simply backmerged those changes. Note, at any time one may
consider origin/master as an immutable (at the point of a given change).
It might be better (if no urgent need) to wait for rc2 and merge it before
doing other changes.

-- 
With Best Regards,
Andy Shevchenko