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Date:   Thu, 10 Aug 2023 12:02:50 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Arnd Bergmann <arnd@kernel.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org,
        Masahiro Yamada <masahiroy@kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Nicolas Schier <nicolas@fjasle.eu>,
        Sami Tolvanen <samitolvanen@google.com>,
        linux-kbuild@vger.kernel.org
Subject: Re: [PATCH 17/17] [RFC] Makefile.extrawarn: turn on
 missing-prototypes again
Message-ID: <202308101202.EA83B53@keescook>
References: <20230810141947.1236730-1-arnd@kernel.org>
 <20230810141947.1236730-18-arnd@kernel.org>
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On Thu, Aug 10, 2023 at 04:19:35PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> Over the years we went from > 1000 of warnings to under 100 earlier
> this year, and I sent patches to address all the ones that I saw with
> compile testing randcom configs on arm64, arm and x86 kernels. This is a
> really useful warning, as it catches real bugs when there are mismatched
> prototypes. In particular with kernel control flow integrity enabled,
> those are no longer allowed.
> 
> Move the options out of the W=1 section to have them enabled by
> default.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> I'm sure there are still regressions with CONFIG_WERROR when this gets
> turned on, but it's getting very close, so it might be best to already
> enable this in linux-next but wait one extra merge window to have it in
> mainline while the last fixes trickle in.
> ---

Thanks for chasing all of these down!

Reviewed-by: Kees Cook <keescook@chromium.org>

-Kees

-- 
Kees Cook