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Date: Fri, 05 Sep 2014 17:29:28 +0200
From: Lars-Peter Clausen <lars@metafoo.de>
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To: Krzysztof Kozlowski <k.kozlowski@samsung.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Vinod Koul <vinod.koul@intel.com>,
        Michal Simek <michal.simek@xilinx.com>,
        Dan Carpenter <dan.carpenter@oracle.com>, dmaengine@vger.kernel.org,
        linux-kernel@vger.kernel.org
CC: Kyungmin Park <kyungmin.park@samsung.com>,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Subject: Re: [PATCH 1/3] dmaengine: pl330: Do not dereference pl330_thread
 pointer before non-NULL check
References: <1409929466-29506-1-git-send-email-k.kozlowski@samsung.com>
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On 09/05/2014 05:04 PM, Krzysztof Kozlowski wrote:
> Do not dereference the 'struct pl330_thread *thrd' before the check for
> non-NULL value.
>
> This fixes following warning:
> drivers/dma/pl330.c:1376 pl330_submit_req() warn: variable dereferenced before check 'thrd' (see line 1367)

I think we can just drop that whole line of checks, none of them will ever 
be true.

>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> ---
>   drivers/dma/pl330.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
> index d5149aacd2fe..47d82070848d 100644
> --- a/drivers/dma/pl330.c
> +++ b/drivers/dma/pl330.c
> @@ -1364,7 +1364,7 @@ static inline u32 _prepare_ccr(const struct pl330_reqcfg *rqc)
>   static int pl330_submit_req(struct pl330_thread *thrd,
>   	struct dma_pl330_desc *desc)
>   {
> -	struct pl330_dmac *pl330 = thrd->dmac;
> +	struct pl330_dmac *pl330;
>   	struct _xfer_spec xs;
>   	unsigned long flags;
>   	void __iomem *regs;
> @@ -1376,6 +1376,7 @@ static int pl330_submit_req(struct pl330_thread *thrd,
>   	if (!desc || !thrd || thrd->free)
>   		return -EINVAL;
>
> +	pl330 = thrd->dmac;
>   	regs = thrd->dmac->base;
>
>   	if (pl330->state == DYING
>