From mboxrd@z Thu Jan  1 00:00:00 1970
From: Albert ARIBAUD <albert.u.boot@aribaud.net>
Date: Fri, 29 Mar 2013 13:32:26 +0100
Subject: [U-Boot] [PATCH] disk: fix unaligned access in efi partitions
In-Reply-To: <6ff0548717babcbc52d225394549106e659cc303.1364556523.git.marvin24@gmx.de>
References: <6ff0548717babcbc52d225394549106e659cc303.1364556523.git.marvin24@gmx.de>
Message-ID: <20130329133226.3483be02@lilith>
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To: u-boot@lists.denx.de

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.