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Date:   Fri, 26 Jun 2020 13:13:18 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     Masahiro Yamada <masahiroy@kernel.org>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        clang-built-linux <clang-built-linux@googlegroups.com>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>,
        linux-efi <linux-efi@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] kbuild: remove cc-option test of -fno-stack-protector
Message-ID: <202006261312.560B045E@keescook>
References: <20200626185913.92890-1-masahiroy@kernel.org>
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On Fri, Jun 26, 2020 at 12:09:37PM -0700, Nick Desaulniers wrote:
> On Fri, Jun 26, 2020 at 12:00 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
> >  CFLAGS_NO_HARDENING := $(call cc-option, -fno-PIC,) $(call cc-option, -fno-pic,) \
> > -       $(call cc-option, -fno-stack-protector,) \
> > -       $(call cc-option, -fno-stack-protector-all,)
> > +       -fno-stack-protector $(call cc-option, -fno-stack-protector-all)
> 
> Just curious, looks like we could do the same for
> `-fno-stack-protector-all`, here or tree-wide, right?  Wait, what
> compiler recognizes -fno-stack-protector-all?
> https://godbolt.org/z/QFQKE_

That is from ancient times, IIRC. -fno-stack-protector should be
sufficient.

-- 
Kees Cook