Re: [PATCH][RESEND] block: sed-opal: fix u64 short atom length

[Derrick, Jonathan]

Hi Jonas,

On Thu, 2018-03-01 at 14:27 +0100, Jonas Rabenstein wrote:
> The length must be given as bytes and not as 4 bit tuples.
> 
> Signed-off-by: Jonas Rabenstein <jonas.rabenstein@xxxxxxxxxxxxxxxxxxx
> n.de>
> ---
>  block/sed-opal.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/block/sed-opal.c b/block/sed-opal.c
> index 36842bfa572e..d5f565e1557a 100644
> --- a/block/sed-opal.c
> +++ b/block/sed-opal.c
> @@ -562,7 +562,7 @@ static void add_token_u64(int *err, struct
> opal_dev *cmd, u64 number)
>  	}
>  
>  	msb = fls(number);
> -	len = DIV_ROUND_UP(msb, 4);
> +	len = DIV_ROUND_UP(msb, 8);

This change looks partially correct, but I believe we should be doing
fls64() on 'number' as well.

It looks like it currently coincidentally works with u64 numbers
falling in 32-bit ranges.


>  
>  	if (cmd->pos >= IO_BUFFER_LENGTH - len - 1) {
>  		pr_debug("Error adding u64: end of buffer.\n");

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