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Subject: Re: [PATCH] ide: fix warning comparing pointer to 0
To:     Jiapeng Chong <jiapeng.chong@linux.alibaba.com>,
        davem@davemloft.net
Cc:     mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org,
        linux-ide@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        linux-kernel@vger.kernel.org
References: <1615456086-127803-1-git-send-email-jiapeng.chong@linux.alibaba.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <034a3feb-27b3-a349-6dcf-75cb36a34e23@kernel.dk>
Date:   Thu, 11 Mar 2021 08:12:10 -0700
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On 3/11/21 2:48 AM, Jiapeng Chong wrote:
> Fix the following coccicheck warning:
> 
> ./drivers/ide/pmac.c:1680:38-39: WARNING comparing pointer to 0.
> 
> Reported-by: Abaci Robot <abaci@linux.alibaba.com>
> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
> ---
>  drivers/ide/pmac.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/ide/pmac.c b/drivers/ide/pmac.c
> index ea0b064..d5171e0 100644
> --- a/drivers/ide/pmac.c
> +++ b/drivers/ide/pmac.c
> @@ -1677,7 +1677,7 @@ static int pmac_ide_init_dma(ide_hwif_t *hwif, const struct ide_port_info *d)
>  	/* We won't need pci_dev if we switch to generic consistent
>  	 * DMA routines ...
>  	 */
> -	if (dev == NULL || pmif->dma_regs == 0)
> +	if (!dev || pmif->dma_regs)
>  		return -ENODEV;

This looks utterly broken - the warning is most definitely about
dma_regs, not dev, and you swapped the condition (failing on dma_regs
being set, not NULL).

I'd just leave this one alone, drivers/ide/ should be going away soon.

-- 
Jens Axboe