Re: [PATCH v3 11/11] selftests: error out if kernel header files are not yet built

[David Hildenbrand]

On 03.11.23 13:59, David Hildenbrand wrote:
> On 03.11.23 13:46, Peter Zijlstra wrote:
> > On Fri, Nov 03, 2023 at 01:22:54PM +0100, David Hildenbrand wrote:
> > > On 03.11.23 13:16, Peter Zijlstra wrote:
> > > > On Tue, Jun 06, 2023 at 12:16:37AM -0700, John Hubbard wrote:
> > > > > As per a discussion with Muhammad Usama Anjum [1], the following is how
> > > > > one is supposed to build selftests:
> > > > >
> > > > >        make headers && make -C tools/testing/selftests/mm
> > > > >
> > > > > Change the selftest build system's lib.mk to fail out with a helpful
> > > > > message if that prerequisite "make headers" has not been done yet.
> > > >
> > > > NAK NAK NAK
> > > >
> > > > This now means I can no longer run selftests, I thank you very much! :-/
> > > >
> > > > root@spr:/usr/src/linux-2.6# make O=defconfig-build/ -j64
> > > > make[1]: Entering directory '/usr/src/linux-2.6/defconfig-build'
> > > > ***
> > > > *** The source tree is not clean, please run 'make mrproper'
> > > > *** in /usr/src/linux-2.6
> > > >
> > > >
> > > > I've always done:
> > > >
> > > >      cd tools/testing/selftests/x86; make
> > > >
> > > > and that has always worked
> > > >
> > > > Now I can't bloody well build *any* selftest or risk not being able to
> > > > do builds.
> > >
> > > This change landed in 6.5, no? And 6.6 was just released. Just curious why
> > > you notice that now.
> >
> > Dunno, last time I edited the selftests and needed to recompile was a
> > few weeks ago.
>
> Okay. the question is if your workflow can be easily adjusted, or if we
> can improve that header handling as a whole.
>
> The problem I had with this recently: just because we did a "make
> headers" once in a git tree doesn't mean that it is still up-to-date.
>
> So once some selftest changes showed up that require newer headers,
> building the selftests again fails without a hint that another round of
> "make headers" would be required.

To clarify: maybe some kind of a warning would be better, ideally that 
the headers might be outdated and that another "make headers" would be 
required in case there are any build errors.

--
Cheers,

David / dhildenb