[U-Boot] [PATCH] efi_loader: Disable env_save() call on boot

[Heinrich Schuchardt]

On 10/19/2017 11:23 PM, Alexander Graf wrote:
> With the introduction of EFI variable support, we also wanted to persist
> these EFI variables. However, the way it was implemented we ended up
> persisting all U-Boot environment variables on every EFI boot.
> 
> That could potentially lead to unexpected side effects because variables
> that were not supposed to be written to persisted env get written. It also
> means we may end up writing the environment more often than we should.
> 
> For this release, let's just disable EFI variable persistence and instead
> implement it properly for the next one.
> 
> Reported-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
> Fixes: ad644e7c182 ("efi_loader: efi variable support")
> Signed-off-by: Alexander Graf <agraf at suse.de>
> ---
>  lib/efi_loader/efi_boottime.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
> index f627340de4..743b84864f 100644
> --- a/lib/efi_loader/efi_boottime.c
> +++ b/lib/efi_loader/efi_boottime.c
> @@ -1439,10 +1439,7 @@ static efi_status_t EFIAPI efi_exit_boot_services(void *image_handle,
>  	/* Make sure that notification functions are not called anymore */
>  	efi_tpl = TPL_HIGH_LEVEL;
>  
> -#if defined(CONFIG_CMD_SAVEENV) && !defined(CONFIG_ENV_IS_NOWHERE)
> -	/* save any EFI variables that have been written: */
> -	env_save();
> -#endif
> +	/* XXX Should persist EFI variables here */
>  
>  	board_quiesce_devices();
>  
> 
Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>