Re: [PATCH 1/2] x86/efi: Correct a tiny mistake in code comment

From: Dave Young
Date: Wed Mar 08 2017 - 03:18:36 EST


On 03/08/17 at 03:47pm, Baoquan He wrote:
> EFI allocate runtime services regions down from EFI_VA_START, -4G.
> It should be top-down handling.
>
> Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
> ---
> arch/x86/platform/efi/efi_64.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
> index a4695da..6cbf9e0 100644
> --- a/arch/x86/platform/efi/efi_64.c
> +++ b/arch/x86/platform/efi/efi_64.c
> @@ -47,7 +47,7 @@
> #include <asm/pgalloc.h>
>
> /*
> - * We allocate runtime services regions bottom-up, starting from -4G, i.e.
> + * We allocate runtime services regions top-down, starting from -4G, i.e.

Baoquan, I think original bottom-up is right, it is just considering
-68G as up, see the x86_64 mm.txt. We regard vmalloc as higher address
although from mathematics view it is lower then positive addresses.

> * 0xffff_ffff_0000_0000 and limit EFI VA mapping space to 64G.
> */
> static u64 efi_va = EFI_VA_START;
> --
> 2.5.5
>

Thanks
Dave