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 for linux-mtd@lists.infradead.org; Fri, 20 Apr 2018 22:40:27 +0000
Date: Sat, 21 Apr 2018 00:40:14 +0200
From: Boris Brezillon <boris.brezillon@bootlin.com>
To: Sam Lefebvre <sam.lefebvre@essensium.com>
Cc: linux-mtd@lists.infradead.org, Han Xu <han.xu@nxp.com>
Subject: Re: [PATCH 07/18] mtd: rawnand: gpmi: return generated errors in
 gpmi_ecc_read_oob()
Message-ID: <20180421004014.79b70616@bbrezillon>
In-Reply-To: <20180420081946.16088-8-sam.lefebvre@essensium.com>
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 <20180420081946.16088-8-sam.lefebvre@essensium.com>
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On Fri, 20 Apr 2018 10:19:35 +0200
Sam Lefebvre <sam.lefebvre@essensium.com> wrote:

> Errors can be generated by nand_read_page_op(). It's important
> to check the error flags and pass them upwards.
> 
> Signed-off-by: Sam Lefebvre <sam.lefebvre@essensium.com>
> ---
>  drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> index 7ba00b8ab288..3da4c07ce2d9 100644
> --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> @@ -1334,13 +1334,18 @@ static int gpmi_ecc_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
>  				int page)
>  {
>  	struct gpmi_nand_data *this = nand_get_controller_data(chip);
> +	int ret;
>  
>  	dev_dbg(this->dev, "page number is %d\n", page);
>  	/* clear the OOB buffer */
>  	memset(chip->oob_poi, ~0, mtd->oobsize);
>  
>  	/* Read out the conventional OOB. */
> -	nand_read_page_op(chip, page, mtd->writesize, NULL, 0);
> +	ret = nand_read_page_op(chip, page, mtd->writesize, NULL, 0);
> +
> +	if (ret)
> +		return ret;
> +
>  	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
>  
>  	/*
> @@ -1350,11 +1355,11 @@ static int gpmi_ecc_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
>  	 */
>  	if (GPMI_IS_MX23(this)) {
>  		/* Read the block mark into the first byte of the OOB buffer. */
> -		nand_read_page_op(chip, page, 0, NULL, 0);
> +		ret = nand_read_page_op(chip, page, 0, NULL, 0);

In case of error, you should bail out before calling ->read_byte().

>  		chip->oob_poi[0] = chip->read_byte(mtd);
>  	}
>  
> -	return 0;
> +	return ret;
>  }
>  
>  static int