Re: [PATCH v2 3/2] docs: changes: better document Python needs

[Mauro Carvalho Chehab <mchehab+huawei@kernel.org>]

Em Sat, 12 Jul 2025 19:31:55 +0300
Laurent Pinchart <laurent.pinchart@ideasonboard.com> escreveu:

> Hi Mauro,
> 
> Thank you for the patch.
> 
> On Sat, Jul 12, 2025 at 10:32:38AM +0200, Mauro Carvalho Chehab wrote:
> > Python is listed as an optional dependency, but this is not
> > true, as kernel-doc is called during compilation when DRM is
> > enabled. Better document that.
> > 
> > Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>  
> 
> Isn't it only when CONFIG_DRM_HEADER_TEST is enabled ? That option
> depends on EXPERT && BROKEN, so I wouldn't expect it to be widely
> enabled. A quick grep shows that CONFIG_DRM_I915_WERROR does the same
> (with a dependency on EXPERT but not BROKEN though).

Well, EXPERT is currently enabled on several distros. The three ones I have
it handy all have it:

Fedora 42:
	$ grep CONFIG_EXPERT /boot/config*
	/boot/config-6.14.9-300.fc42.x86_64:CONFIG_EXPERT=y
	/boot/config-6.15.3-200.fc42.x86_64:CONFIG_EXPERT=y
	/boot/config-6.15.4-200.fc42.x86_64:CONFIG_EXPERT=y

Ubuntu 24.10:
	$ grep CONFIG_EXPERT /boot/config*
	/boot/config-6.11.0-26-generic:CONFIG_EXPERT=y
	/boot/config-6.8.0-60-generic:CONFIG_EXPERT=y

Debian 12:
	$ grep CONFIG_EXPERT /boot/config*
	/boot/config-6.1.0-34-amd64:CONFIG_EXPERT=y
	/boot/config-6.1.0-37-amd64:CONFIG_EXPERT=y
	/boot/config-6.1.0-37-rt-amd64:CONFIG_EXPERT=y

So, expert on distros seem quite common those days.

Fedora has it enabled for a long time. On Fedora 42:

	$ grep CONFIG_DRM_WERROR /boot/config*
	/boot/config-6.14.9-300.fc42.x86_64:CONFIG_DRM_WERROR=y
	/boot/config-6.15.3-200.fc42.x86_64:CONFIG_DRM_WERROR=y
	/boot/config-6.15.4-200.fc42.x86_64:CONFIG_DRM_WERROR=y

I would expect to have it enabled on other distros as well.

> Is there something else in DRM that invokes kernel-doc ?
> 
> > ---
> >  Documentation/process/changes.rst | 9 ++++++++-
> >  1 file changed, 8 insertions(+), 1 deletion(-)
> > 
> > diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
> > index bccfa19b45df..6a7d7c1ee274 100644
> > --- a/Documentation/process/changes.rst
> > +++ b/Documentation/process/changes.rst
> > @@ -61,7 +61,7 @@ Sphinx\ [#f1]_         3.4.3            sphinx-build --version
> >  GNU tar                1.28             tar --version
> >  gtags (optional)       6.6.5            gtags --version
> >  mkimage (optional)     2017.01          mkimage --version
> > -Python (optional)      3.9.x            python3 --version
> > +Python                 3.9.x            python3 --version
> >  GNU AWK (optional)     5.1.0            gawk --version
> >  ====================== ===============  ========================================
> >  
> > @@ -154,6 +154,13 @@ Perl
> >  You will need perl 5 and the following modules: ``Getopt::Long``,
> >  ``Getopt::Std``, ``File::Basename``, and ``File::Find`` to build the kernel.
> >  
> > +Python
> > +------
> > +
> > +At least Python 2.7 or 3.4 is required if CONFIG_DRM is selected to avoid
> > +breaking compilation. Documentation build and kernel-doc won't produce
> > +valid results if version is below 3.7.

Maybe I can place instead CONFIG_DRM_I915_WERROR.


Thanks,
Mauro