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From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Fri, 10 Apr 2020 10:20:42 +0200
Message-ID: <CAMj1kXFhtK=FRDKBE5OtenNEtpK=kVwyo+0nqJZ_K80RmtYxEg@mail.gmail.com>
Subject: Re: [PATCH 3/9] efi/x86: Move efi stub globals from .bss to .data
To:     Arvind Sankar <nivedita@alum.mit.edu>
Cc:     Brian Gerst <brgerst@gmail.com>,
        linux-efi <linux-efi@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Arnd Bergmann <arnd@arndb.de>, Borislav Petkov <bp@suse.de>,
        Colin Ian King <colin.king@canonical.com>,
        Gary Lin <glin@suse.com>, Jiri Slaby <jslaby@suse.cz>,
        Sergey Shatunov <me@prok.pw>, Takashi Iwai <tiwai@suse.de>
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On Thu, 9 Apr 2020 at 23:08, Arvind Sankar <nivedita@alum.mit.edu> wrote:
>
> On Thu, Apr 09, 2020 at 04:53:07PM -0400, Brian Gerst wrote:
> > > Can we use the -fno-zero-initialized-in-bss compiler flag instead of
> > > explicitly marking global variables?
> >
> > Scratch that.  Apparently it only works when a variable is explicitly
> > initialized to zero.
> >
> > --
> > Brian Gerst
>
> Right, there doesn't seem to be a compiler option to turn off the use of
> .bss altogether.

Yeah. I'll try to come up with a way to consolidate this a bit across
architectures (which is a bit easier now that all of the EFI stub C
code lives in the same place). It is probably easiest to use a section
renaming trick similar to the one I added for ARM (as Arvind suggested
as well, IIRC), and get rid of the per-symbol annotations altogether.