linux-mips
[Top] [All Lists]

Re: [PATCH v2 2/6] Add new NOSAVE_DATA linker script macro.

To: Tim Abbott <tabbott@MIT.EDU>
Subject: Re: [PATCH v2 2/6] Add new NOSAVE_DATA linker script macro.
From: Sam Ravnborg <sam@ravnborg.org>
Date: Fri, 1 May 2009 11:21:14 +0200
Cc: Linux kernel mailing list <linux-kernel@vger.kernel.org>, Anders Kaseorg <andersk@mit.edu>, Waseem Daher <wdaher@mit.edu>, Denys Vlasenko <vda.linux@googlemail.com>, Jeff Arnold <jbarnold@mit.edu>, Benjamin Herrenschmidt <benh@kernel.crashing.org>, Bryan Wu <cooloney@kernel.org>, Chris Zankel <chris@zankel.net>, Cyrill Gorcunov <gorcunov@openvz.org>, David Howells <dhowells@redhat.com>, "David S. Miller" <davem@davemloft.net>, dev-etrax@axis.com, Geert Uytterhoeven <geert@linux-m68k.org>, Greg Ungerer <gerg@uclinux.org>, Haavard Skinnemoen <hskinnemoen@atmel.com>, Heiko Carstens <heiko.carstens@de.ibm.com>, Helge Deller <deller@gmx.de>, Hirokazu Takata <takata@linux-m32r.org>, "H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>, Jeff Dike <jdike@addtoit.com>, Jesper Nilsson <jesper.nilsson@axis.com>, Kyle McMartin <kyle@mcmartin.ca>, Linus Torvalds <torvalds@linux-foundation.org>, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@vger.kernel.org, linux-mips@linux-mips.org, linux-parisc@vger.kernel.org, linuxppc-dev@ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, Martin Schwidefsky <schwidefsky@de.ibm.com>, Michal Simek <monstr@monstr.eu>, microblaze-uclinux@itee.uq.edu.au, Mikael Starvik <starvik@axis.com>, Paul Mackerras <paulus@samba.org>, Paul Mundt <lethal@linux-sh.org>, Ralf Baechle <ralf@linux-mips.org>, Richard Henderson <rth@twiddle.net>, Roman Zippel <zippel@linux-m68k.org>, Russell King <rmk+kernel@arm.linux.org.uk>, sparclinux@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>, Tony Luck <tony.luck@intel.com>, uclinux-dist-devel@blackfin.uclinux.org, user-mode-linux-devel@lists.sourceforge.net, Yoshinori Sato <ysato@users.sourceforge.jp>
In-reply-to: <1241121253-32341-3-git-send-email-tabbott@mit.edu>
Original-recipient: rfc822;linux-mips@linux-mips.org
References: <1241121253-32341-1-git-send-email-tabbott@mit.edu> <1241121253-32341-2-git-send-email-tabbott@mit.edu> <1241121253-32341-3-git-send-email-tabbott@mit.edu>
Sender: linux-mips-bounce@linux-mips.org
User-agent: Mutt/1.4.2.1i
On Thu, Apr 30, 2009 at 03:54:09PM -0400, Tim Abbott wrote:
> This patch is preparation for replacing most ".data.nosave" in the
> kernel with macros, so that the section name can later be changed
> without having to touch a lot of the kernel.
> 
> The long-term goal here is to be able to change the kernel's magic
> section names to those that are compatible with -ffunction-sections
> -fdata-sections.  This requires renaming all magic sections with names
> of the form ".data.foo".
> 
> Signed-off-by: Tim Abbott <tabbott@mit.edu>
> Cc: Sam Ravnborg <sam@ravnborg.org>
> ---
>  include/asm-generic/vmlinux.lds.h |    7 +++++++
>  1 files changed, 7 insertions(+), 0 deletions(-)
> 
> diff --git a/include/asm-generic/vmlinux.lds.h 
> b/include/asm-generic/vmlinux.lds.h
> index 3d88c87..f5ebd2b 100644
> --- a/include/asm-generic/vmlinux.lds.h
> +++ b/include/asm-generic/vmlinux.lds.h
> @@ -124,6 +124,13 @@
>       . = ALIGN(PAGE_SIZE);                                           \
>       *(.bss.page_aligned)
>  
> +#define NOSAVE_DATA                                                  \
> +     . = ALIGN(PAGE_SIZE);                                           \
> +     __nosave_begin = .;                                             \
> +     *(.data.nosave)                                                 \
> +     . = ALIGN(PAGE_SIZE);                                           \
> +     __nosave_end = .;
> +

You need to use:
        VMLINUX_SYMBOL(__nosave_begin) = .;

Otherwise architectures such as m68k wil break as they
add a leading underscore.

See other symbols that is defined inside vmlinux.lds.h

        Sam

<Prev in Thread] Current Thread [Next in Thread>
  • Re: [PATCH v2 2/6] Add new NOSAVE_DATA linker script macro., Sam Ravnborg <=