Re: [PATCH 2/2] x86_64: Remove CONFIG_PHYSICAL_START and CONFIG_RELOCATABLE

[Vivek Goyal <vgoyal@in.ibm.com>]

On Sun, Apr 22, 2007 at 11:15:48PM -0600, Eric W. Biederman wrote:
> 
> Now that the vmlinux is marked as relocatable there is no reason to
> retain the CONFIG_PHYSICAL_START option, as we can put the binary we
> have at any 2MB aligned address in memory.
> 
> With CONFIG_PHYSICAL_START gone the handful of code lines that depend
> on CONFIG_RELOCATABLE no longer make sense to be conditional and can
> be removed.
> 
> The big win of this patch (besides Kconfig simplicity) is that the
> nasty BUILD_BUG_ON test for people misaligning their kernel when using
> CONFIG_PHYSICAL_START can be removed as this case can only happen with
> CONFIG_PHYSICAL_START selected.
> 
> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
> ---
>  arch/x86_64/Kconfig                |   55 +-----------------------------------
>  arch/x86_64/Makefile               |    2 -
>  arch/x86_64/boot/compressed/head.S |   13 +--------
>  arch/x86_64/boot/setup.S           |    4 --
>  arch/x86_64/defconfig              |    2 -
>  arch/x86_64/kernel/head64.c        |    7 ----
>  include/asm-x86_64/page.h          |    2 +-
>  7 files changed, 3 insertions(+), 82 deletions(-)
> 
> diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
> index 773b487..713c1ad 100644
> --- a/arch/x86_64/Kconfig
> +++ b/arch/x86_64/Kconfig
> @@ -565,62 +565,9 @@ config CRASH_DUMP
>            which are loaded in the main kernel with kexec-tools into
>            a specially reserved region and then later executed after
>            a crash by kdump/kexec. The crash dump kernel must be compiled
> -	  to a memory address not used by the main kernel or BIOS using
> -	  PHYSICAL_START.
> +	  to a memory address not used by the main kernel or BIOS
>            For more details see Documentation/kdump/kdump.txt

Hi Eric,

I think "must be compiled" should be replaced with "must be loaded" now.

Otherwise both the patches look fine.  I am planning to test these.

This change will also require modifications to Documentation/kdump/kdump.txt
file.

Thanks
Vivek