Subject: Re: [PATCH] ata: pata_pxa: Add missing check for devm_ioremap
To:     Jiasheng Jiang <jiasheng@iscas.ac.cn>,
        <damien.lemoal@opensource.wdc.com>
CC:     <linux-ide@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20230209092814.10847-1-jiasheng@iscas.ac.cn>
From:   Sergey Shtylyov <s.shtylyov@omp.ru>
Organization: Open Mobile Platform
Message-ID: <1b08e3fb-d1fc-80f2-82f8-873812c0fc8c@omp.ru>
Date:   Thu, 9 Feb 2023 12:54:03 +0300
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On 2/9/23 12:28 PM, Jiasheng Jiang wrote:

> Add the check for the return value of the devm_ioremap in order to avoid
> NULL pointer dereference.
> 
> Fixes: 2dc6c6f15da9 ("[ARM] pata_pxa: DMA-capable PATA driver")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  drivers/ata/pata_pxa.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/ata/pata_pxa.c b/drivers/ata/pata_pxa.c
> index 985f42c4fd70..a20bb0824573 100644
> --- a/drivers/ata/pata_pxa.c
> +++ b/drivers/ata/pata_pxa.c
> @@ -227,6 +227,8 @@ static int pxa_ata_probe(struct platform_device *pdev)
>  						resource_size(ctl_res));
>  	ap->ioaddr.bmdma_addr	= devm_ioremap(&pdev->dev, dma_res->start,
>  						resource_size(dma_res));
> +	if (!ap->ioaddr.cmd_addr || !ap->ioaddr.ctl_addr || !ap->ioaddr.bmdma_addr)
> +		return -ENOMEM;

   Such patch has been postyed already but the driver is more broken than just
ths check missing, see:

https://lore.kernel.org/all/20220612073222.18974-1-liqiong@nfschina.com/

MBR, Sergey