Re: [Outreachy kernel] Re: [PATCH v2 1/5] staging: octeon: remove typedef declaration for cvmx_wqe

[Julia Lawall]

On Thu, 24 Oct 2019, Paul Burton wrote:

> Hi Wambui, Julia,
>
> Side-note: Wambui, your mail client seems to have added this header:
>
>   Reply-To: alpine.DEB.2.21.1910240722070.2771@hadrien
>
> This is the ID of the message you replied to (ie. this is the same value
> that the In-Reply-To: header has). You should probably figure out how
> that happened, or you're going to miss responses when people reply
> without noticing the bogus email address.

This is somehow related to me...  I don't know if the problem comes from
me or from Wambui.

julia

>
> On Thu, Oct 24, 2019 at 01:00:20PM +0300, Wambui Karuga wrote:
> > On Thu, Oct 24, 2019 at 07:26:59AM +0200, Julia Lawall wrote:
> > > > If you're making significant changes to this driver, please test them
> > > > using the MIPS cavium_octeon_defconfig which is where this driver is
> > > > actually used.
> > > >
> > > > This driver has broken builds a few times recently which makes me very
> > > > tempted to ask that we stop allowing it to be built with COMPILE_TEST.
> > > > The whole octeon-stubs.h thing is a horrible hack anyway...
> > >
> > > Wambui,
> > >
> > > Please figure out what went wrong here.  Are there two sets of typedefs
> > > that should have been updated?
> > >
> > I managed to reproduce these build errors and finally noticed that the
> > "octeon-stubs.h" header is only included when CONFIG_CAVIUM_OCTEON_SOC
> > is not defined, therefore compiling properly for COMPILE_TEST but will
> > actually fail when compiled with CONFIG_CAVIUM_OCTEON_SOC is set since
> > the functions will try to use the definitions in
> > arch/mips/include/asm/octeon/ that don't have the changes.
> >
> > Paul, please tell me if this is correct?
>
> Yes, that's correct. The driver was written to use the headers in
> arch/mips/include/asm/octeon, and then recently the octeon-stubs.h
> header was added which duplicates lots of the MIPS & Octeon-specific
> header content in one huge monstrous file.
>
> I'm all for improving compile test coverage, but I think octeon-stubs.h
> in its short life has already proven itself to be a bad way to achieve
> that goal[1][2][3].
>
> > > Others,
> > >
> > > Would it be reasonable to put the information about how the driver should
> > > be compied in the TODO file?  git grep cavium_octeon_defconfig in the
> > > octeon directory turns up nothing.
>
> It wouldn't hurt. I'd argue that Kconfig already provides enough
> information to figure this out easily though - OCTEON_ETHERNET depends
> on CAVIUM_OCTEON_SOC || COMPILE_TEST, which ought to tell people that
> its real use is when CAVIUM_OCTEON_SOC=y. That doesn't necessarily point
> you to cavium_octeon_defconfig (though grepping for CAVIUM_OCTEON_SOC=y
> would), but that's not strictly needed anyway - any old config with
> CAVIUM_OCTEON_SOC=y would do.
>
> Thanks,
>     Paul
>
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0228ecf6128c92b47eadd2ac270c5574d9150c09
> [2] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/staging/octeon?id=17a29fea086ba18b000d28439bd5cb4f2b0a527b
> [3] https://storage.kernelci.org/next/master/next-20191024/mips/cavium_octeon_defconfig/gcc-8/build.log
>