Re: [PATCH 0/2] Stop generating .eh_frame sections

From: Arvind Sankar
Date: Mon Feb 24 2020 - 16:53:37 EST


On Mon, Feb 24, 2020 at 12:49:03PM -0800, Nick Desaulniers wrote:
> On Sun, Feb 23, 2020 at 11:37 AM Arvind Sankar <nivedita@xxxxxxxxxxxx> wrote:
> >
> > 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
>
> Thanks for the series! I've left some feedback for a v2. Would you
> mind please including a revert of ("x86/boot/compressed: Remove
> unnecessary sections from bzImage") in a v2 series? Our CI being red
> through the weekend is no bueno.

Sorry about that. Boris already updated tip:x86/boot to only discard
eh_frame, so your CI should be ok at least now.

>
> >
> > 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
> >
>
>
> --
> Thanks,
> ~Nick Desaulniers