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Date:   Fri, 26 Jun 2020 13:18:56 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     linux-kbuild@vger.kernel.org, clang-built-linux@googlegroups.com,
        x86@kernel.org, linux-efi@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] kbuild: remove cc-option test of -fno-stack-protector
Message-ID: <202006261318.75C7FE339@keescook>
References: <20200626185913.92890-1-masahiroy@kernel.org>
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On Sat, Jun 27, 2020 at 03:59:12AM +0900, Masahiro Yamada wrote:
> Some Makefiles already pass -fno-stack-protector unconditionally.
> For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile.
> No problem report so far about hard-coding this option. So, we can
> assume all supported compilers know -fno-stack-protector.
> 
> GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN)
> 
> Get rid of cc-option from -fno-stack-protector.
> 
> Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which should always be 'y'.
> 
> Note:
> arch/mips/vdso/Makefile adds -fno-stack-protector twice, first
> unconditionally, and second conditionally. I removed the second one.
> 
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

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

-- 
Kees Cook