[U-Boot] [PATCH] efi_loader: Fix warning in raw/cols query

[Heinrich Schuchardt]

On 06/03/2018 03:52 PM, Alexander Graf wrote:
> The code to determine rows / cols on the screen could potentially run
> into a case where it doesn't know how big the screen is. In that case,
> assume 80x25.

This patch may silence a compiler warning. But to me it is unclear on
which path of the code we could end up actually using undefined values
of cols or rows without the patch.

If we are copying cols and rows from vidconsole, this patch does not
make a difference.

If we call query_console_serial() that routine either initializes rows
and cols or returns -1 in which case we do not consume rows and cols.

Could you, please, either clearly state that this patch only serves to
silence an invalid compiler warning or identify the path to the
consumption of uninitialized values.

Best regards

Heinrich

> 
> Signed-off-by: Alexander Graf <agraf at suse.de>
> ---
>  lib/efi_loader/efi_console.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/lib/efi_loader/efi_console.c b/lib/efi_loader/efi_console.c
> index 0bfc24dbd9..ce66c935ec 100644
> --- a/lib/efi_loader/efi_console.c
> +++ b/lib/efi_loader/efi_console.c
> @@ -223,7 +223,7 @@ static int query_console_serial(int *rows, int *cols)
>  static void query_console_size(void)
>  {
>  	const char *stdout_name = env_get("stdout");
> -	int rows, cols;
> +	int rows = 25, cols = 80;
>  
>  	if (stdout_name && !strcmp(stdout_name, "vidconsole") &&
>  	    IS_ENABLED(CONFIG_DM_VIDEO)) {
>