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From:   Arvind Sankar <nivedita@alum.mit.edu>
To:     Arvind Sankar <nivedita@alum.mit.edu>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Borislav Petkov <bp@alien8.de>,
        Nathan Chancellor <natechancellor@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com,
        Michael Matz <matz@suse.de>, Fangrui Song <maskray@google.com>,
        Kees Cook <keescook@chromium.org>
Subject: [PATCH 0/2] Stop generating .eh_frame sections
Date:   Sun, 23 Feb 2020 14:37:13 -0500
Message-Id: <20200223193715.83729-1-nivedita@alum.mit.edu>
In-Reply-To: <20200222235709.GA3786197@rani.riverdale.lan>
References: <20200222235709.GA3786197@rani.riverdale.lan>
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Sender: linux-kernel-owner@vger.kernel.org
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In three places in the x86 kernel we are currently generating .eh_frame
sections only to discard them later via linker script. This is in the
boot code (setup.elf), the realmode trampoline (realmode.elf) and the
compressed kernel.

Implement Fangrui and Nick's suggestion [1] to fix KBUILD_CFLAGS by
adding -fno-asynchronous-unwind-tables to avoid generating .eh_frame
sections in the first place, rather than discarding it in the linker
script.

Arvind Sankar (2):
  arch/x86: Use -fno-asynchronous-unwind-tables to suppress .eh_frame sections
  arch/x86: Drop unneeded linker script discard of .eh_frame

 arch/x86/boot/Makefile                | 1 +
 arch/x86/boot/compressed/Makefile     | 1 +
 arch/x86/boot/setup.ld                | 1 -
 arch/x86/kernel/vmlinux.lds.S         | 3 ---
 arch/x86/realmode/rm/Makefile         | 1 +
 arch/x86/realmode/rm/realmode.lds.S   | 1 -
 drivers/firmware/efi/libstub/Makefile | 3 ++-
 7 files changed, 5 insertions(+), 6 deletions(-)

-- 
2.24.1