Re: [PATCH v6 00/10] kbuild: yet another series of cleanups (modpost, LTO, MODULE_REL_CRCS, export.h)

From: Masahiro Yamada <masahiroy@kernel.org>
To: matoro <matoro_mailinglist_kernel@matoro.tk>
Cc: Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Nicolas Schier <nicolas@fjasle.eu>,
	Peter Zijlstra <peterz@infradead.org>,
	linux-modules <linux-modules@vger.kernel.org>,
	clang-built-linux <llvm@lists.linux.dev>,
	Ard Biesheuvel <ardb@kernel.org>,
	Sami Tolvanen <samitolvanen@google.com>
Subject: Re: [PATCH v6 00/10] kbuild: yet another series of cleanups (modpost, LTO, MODULE_REL_CRCS, export.h)
Date: Wed, 10 Aug 2022 00:20:13 +0900	[thread overview]
Message-ID: <CAK7LNASGewXa8bHy1SZNzTi+V5aoHdV6OysY0z76SQNs92iB9Q@mail.gmail.com> (raw)
In-Reply-To: <d4f30a7313f1ff43d0c919fc556f08fe@matoro.tk>

On Tue, Aug 9, 2022 at 3:42 AM matoro
<matoro_mailinglist_kernel@matoro.tk> wrote:
>
> That patch doesn't apply to the v5.19 stable tag, so I just manually
> edited and it worked perfect!  Thank you!!
>
> Sorry I didn't mention that warning - I did see it, but it still showed
> up even on the old kernel, so I thought it was irrelevant.  Much
> appreciated!
>
> -------- Original Message --------
> Subject: Re: [PATCH v6 00/10] kbuild: yet another series of cleanups
> (modpost, LTO, MODULE_REL_CRCS, export.h)
> Date: 2022-08-08 13:36
>  From: Masahiro Yamada <masahiroy@kernel.org>
> To: matoro <matoro_mailinglist_kernel@matoro.tk>
>
> On Mon, Aug 8, 2022 at 10:27 PM matoro
> <matoro_mailinglist_kernel@matoro.tk> wrote:
> >
> > I have real hardware for all these arches in my collection.  I use it
> > for testing the latest kernel and toolchains on as many of the
> > less-popular arches as possible, exactly to find issues like this one
> > :)
> >
> > Specifically we support all of these in Gentoo.  To double-check this
> > wasn't a config issue, I asked another user who also runs sparc to try
> > building 5.19 with his config (not copying mine), and he observed the
> > same problem.  You can reach us in #gentoo-sparc on Libera.
> >
> > As for testing, I make all this hardware available on an as-needed
> > basis.  So if you can't or don't want to fiddle with qemu, just let me
> > know (email or IRC, same username on Libera), and I will get you direct
> > access to my hardware.  Thanks!!
>
>
> I found the root cause.
>
> When I build the sparc kernel, I see a warning
>
> WARNING: modpost: EXPORT symbol "_mcount" [vmlinux] version generation
> failed, symbol will not be versioned.
>
>
> Then, modpost missed to write out the entry.
>
> With the following patch, you will be able to load the module.
>
> I will send a patch with a proper commit log tomorrow. I need some sleep
> now.

I posted a patch:

https://patchwork.kernel.org/project/linux-kbuild/patch/20220809141117.641543-1-masahiroy@kernel.org/

If you want me to record your full name in Reported/Tested-by,
please let me know.

-- 
Best Regards
Masahiro Yamada