Re: [PATCH][mtd-next] mtd: nand: remove redundant check of len

From: Boris Brezillon
Date: Wed Dec 13 2017 - 15:24:37 EST


On Wed, 13 Dec 2017 20:17:43 +0000
Colin King <colin.king@xxxxxxxxxxxxx> wrote:

> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> The check of len being zero is redundant as it has already been
> sanity checked for this value at the start of the function. Hence
> it is impossible for this test to be true and so the redundant
> code can be removed.

Nope, it's not the same test, the initial test is

if (len && !buf)

not

if (len)

So this test is not redundant.

>
> Detected by CoverityScan, CID#1462748 ("Logically dead code")
>
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
> drivers/mtd/nand/nand_base.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
> index afd5e18db81c..9daaa23db943 100644
> --- a/drivers/mtd/nand/nand_base.c
> +++ b/drivers/mtd/nand/nand_base.c
> @@ -1507,10 +1507,6 @@ static int nand_read_param_page_op(struct nand_chip *chip, u8 page, void *buf,
> };
> struct nand_operation op = NAND_OPERATION(instrs);
>
> - /* Drop the DATA_IN instruction if len is set to 0. */
> - if (!len)
> - op.ninstrs--;
> -
> return nand_exec_op(chip, &op);
> }
>