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Message-ID: <dc948948-5d69-e9b1-417b-7d6b8824782c@meizu.com>
Date:   Fri, 22 Apr 2022 14:17:18 +0800
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Subject: Re: [PATCH] dmaengine: imx-sdma: Remove useless null check before
 call of_node_put()
To:     Vinod Koul <vkoul@kernel.org>
CC:     Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        <dmaengine@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>
References: <1650509390-26877-1-git-send-email-baihaowen@meizu.com>
 <YmJGw84by8eczx/u@matsya>
From:   baihaowen <baihaowen@meizu.com>
In-Reply-To: <YmJGw84by8eczx/u@matsya>
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在 4/22/22 2:10 PM, Vinod Koul 写道:
> On 21-04-22, 10:49, Haowen Bai wrote:
>> No need to add null check before call of_node_put(), since the
>> implementation of of_node_put() has done it.
>>
>> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
>> ---
>>  drivers/dma/imx-sdma.c | 3 +--
>>  1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
>> index 6196a7b3956b..b8a1299b93f0 100644
>> --- a/drivers/dma/imx-sdma.c
>> +++ b/drivers/dma/imx-sdma.c
>> @@ -1933,8 +1933,7 @@ static int sdma_event_remap(struct sdma_engine *sdma)
>>  	}
>>  
>>  out:
>> -	if (gpr_np)
>> -		of_node_put(gpr_np);
>> +	of_node_put(gpr_np);
> this is incorrect as it is called on error case
>
>
Even through it is called on error case, gpr_np=null, but  of_node_put
did a null check.
void of_node_put(struct device_node *node)

{ if (node) kobject_put(&node->kobj); }

-- 
Haowen Bai