Re: [PATCH] reserve_early end-of-conventional-memory to 1MB

H. Peter Anvin
2008-02-25T18:14:09Z

Alexander van Heukelum wrote:
>
> arch/x86/kernel/head64.c | 45 +++++++++++++++++++++++++++------------------
> 1 files changed, 27 insertions(+), 18 deletions(-)
>
> diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
> index 38f32e7..b684552 100644
> --- a/arch/x86/kernel/head64.c
> +++ b/arch/x86/kernel/head64.c
> @@ -49,33 +49,42 @@ static void __init copy_bootdata(char *real_mode_data)
> }
> }
>
> -#define EBDA_ADDR_POINTER 0x40E
> +#define BIOS_EBDA_SEGMENT 0x40E
> +#define BIOS_LOWMEM_KILOBYTES 0x413
>

Linus has specific comments in the 32-bit code that states we do not
want to use address 0x413 for anything - if nothing else because it's
often lowered when there is boottime code involved like CD-ROM booting
or PXE.

Either way, the code should be shared between 32 and 64 bits. There is
nothing bitsize-specific about it!

-hpa