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From:   Sami Tolvanen <samitolvanen@google.com>
Date:   Wed, 19 Feb 2020 10:27:33 -0800
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Subject: Re: [PATCH v8 12/12] efi/libstub: disable SCS
To:     Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc:     Will Deacon <will@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        James Morse <james.morse@arm.com>,
        Dave Martin <Dave.Martin@arm.com>,
        Kees Cook <keescook@chromium.org>,
        Laura Abbott <labbott@redhat.com>,
        Marc Zyngier <maz@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Jann Horn <jannh@google.com>,
        Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        clang-built-linux <clang-built-linux@googlegroups.com>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Tue, Feb 18, 2020 at 11:41 PM Ard Biesheuvel
<ard.biesheuvel@linaro.org> wrote:
>
> On Wed, 19 Feb 2020 at 01:09, Sami Tolvanen <samitolvanen@google.com> wrote:
> >
> > +#  remove SCS flags from all objects in this directory
> > +KBUILD_CFLAGS := $(filter-out -ffixed-x18 $(CC_FLAGS_SCS), $(KBUILD_CFLAGS))
> > +
>
> I don't see why you'd need to remove -ffixed-x18 again here. Not using
> x18 anywhere in the kernel is a much more maintainable approach.

Sure, I will drop -ffixed-x18 from here in v9. Thanks,

Sami