Re: [PATCH 3/5] x86/boot/64: Change add_identity_map() to take size for ease of use

Joerg Roedel
2020-10-08T09:14:16Z

On Wed, Oct 07, 2020 at 03:53:49PM -0400, Arvind Sankar wrote:
> Change back the arguments of add_identity_map() to (start, size) instead
> of (start, end). This reverts
>
> 21cf2372618e ("x86/boot/compressed/64: Change add_identity_map() to take start and end")
>
> since we will soon have more callers that know the size rather than the
> end address.
>
> This also makes the #PF handler print the original CR2 value in case of
> error, instead of after aligning to PMD_SIZE.
>
> Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
> ---
> arch/x86/boot/compressed/ident_map_64.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c
> index 063a60edcf99..070cda70aef3 100644
> --- a/arch/x86/boot/compressed/ident_map_64.c
> +++ b/arch/x86/boot/compressed/ident_map_64.c
> @@ -90,8 +90,9 @@ static struct x86_mapping_info mapping_info;
> /*
> * Adds the specified range to the identity mappings.
> */
> -static void add_identity_map(unsigned long start, unsigned long end)
> +static void add_identity_map(unsigned long start, unsigned long size)
> {
> + unsigned long end = start + size;

This has been discussed during the SEV-ES patch-review already and we
settled on making add_identity_map() take start and end as parameter, as
that is what kernel_ident_mapping_init() also takes as parameters.

So please keep it that way :)

Regards,

Joerg