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Date:   Wed, 3 Mar 2021 13:15:16 -0600
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Michal Marek <michal.lkml@markovi.net>,
        linux-hardening@vger.kernel.org,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Justin Forbes <jforbes@redhat.com>,
        Ondrej Mosnacek <omosnace@redhat.com>,
        Frank Eigler <fche@redhat.com>,
        Kees Cook <keescook@chromium.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH RFC] gcc-plugins: Handle GCC version mismatch for OOT
 modules
Message-ID: <20210303191516.6ksxmng4pis7ue4p@treble>
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 <CAK7LNAReuB5zUq_7S8ZG25+tdQowECDOK1rApYvkPCpHhPjK5w@mail.gmail.com>
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On Thu, Mar 04, 2021 at 03:49:35AM +0900, Masahiro Yamada wrote:
> > This problem is becoming more prevalent.  We will need to fix it one way
> > or another, if we want to support distro adoption of these GCC
> > plugin-based features.
> >
> > Frank suggested a possibly better idea: always rebuild the plugins when
> > the GCC version changes.
> 
> 
> That is just another form of the previous patch,
> which was already rejected.
> 
> 
> - That is a hack just for external modules
> - Our consensus is, use the same version for the kernel and external modules
> 
> 
> 
> I use Ubuntu, and I do not see such a problem.
> (I have never seen it on Debian either, except sid.)
> 
> I see Fedora providing GCC whose version is different
> from the one used for building the kernel.
> That is a problem on the distribution side.

I don't understand.  Are you suggesting that a distro should always
release GCC and kernel updates simultaneously?

How is this problem specific to Fedora?  Please be specific about what
Ubuntu and Debian do, which Fedora doesn't do.

Adding Linus, who indicated in another thread that we shouldn't force
exact GCC versions because there's no technical reason to do so.

-- 
Josh