[U-Boot] [PATCH] disk: fix unaligned access in efi partitions

Albert ARIBAUD
2013-03-29T12:32:26Z

Hi Marc,

On Fri, 29 Mar 2013 12:28:58 +0100, Marc Dietrich <marvin24@gmx.de>
wrote:

> start_sect is not aligned to a 4 byte boundary thus causing exceptions
> on ARM platforms. Access this field via the get_unaligned macro.
>
> Signed-off-by: Marc Dietrich <marvin24@gmx.de>
> ---
> disk/part_efi.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/disk/part_efi.c b/disk/part_efi.c
> index b3fd0e9..6678a4c 100644
> --- a/disk/part_efi.c
> +++ b/disk/part_efi.c
> @@ -30,6 +30,7 @@
> *
> * This limits the maximum size of addressable storage to < 2 Terra Bytes
> */
> +#include <asm/unaligned.h>
> #include <common.h>
> #include <command.h>
> #include <ide.h>
> @@ -505,7 +506,7 @@ err:
> static int pmbr_part_valid(struct partition *part)
> {
> if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
> - le32_to_cpu(part->start_sect) == 1UL) {
> + le32_to_cpu(get_unaligned(&part->start_sect)) == 1UL) {
> return 1;
> }

Suits me :) but did you not say the same issue was also affecting
nr_sects?

Also, beside the asm/unaligned.h file I gave as an example, other header
files in include/linux/unaligned/ exist that provide alignment-related
macros, notably with _le and _be versions. Maybe you can find one that
combines the effects of both le32_to_cpu() and get_unaligned()?

Amicalement,
--
Albert.