Local variable chan is initialized by an address of element of chan array
that is part of stm32_mdma_device struct, so it does not make sense to
compare chan with NULL.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Fixes: a4ffb13c8946 ("dmaengine: Add STM32 MDMA driver")
---
 drivers/dma/stm32-mdma.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
index caf0cce8f528..b11927ed4367 100644
--- a/drivers/dma/stm32-mdma.c
+++ b/drivers/dma/stm32-mdma.c
@@ -1328,12 +1328,7 @@ static irqreturn_t stm32_mdma_irq_handler(int irq, void *devid)
 		return IRQ_NONE;
 	}
 	id = __ffs(status);
-
 	chan = &dmadev->chan[id];
-	if (!chan) {
-		dev_warn(mdma2dev(dmadev), "MDMA channel not initialized\n");
-		return IRQ_NONE;
-	}
 
 	/* Handle interrupt for the channel */
 	spin_lock(&chan->vchan.lock);
-- 
2.7.4

On 13-06-22, 01:23, Alexey Khoroshilov wrote:
> Local variable chan is initialized by an address of element of chan array
> that is part of stm32_mdma_device struct, so it does not make sense to
> compare chan with NULL.

Applied, thanks

-- 
~Vinod

Hi Alexey,

On 6/13/22 00:23, Alexey Khoroshilov wrote:
> Local variable chan is initialized by an address of element of chan array
> that is part of stm32_mdma_device struct, so it does not make sense to
> compare chan with NULL.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
> Fixes: a4ffb13c8946 ("dmaengine: Add STM32 MDMA driver")
> ---
>   drivers/dma/stm32-mdma.c | 5 -----
>   1 file changed, 5 deletions(-)
> 
> diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
> index caf0cce8f528..b11927ed4367 100644
> --- a/drivers/dma/stm32-mdma.c
> +++ b/drivers/dma/stm32-mdma.c
> @@ -1328,12 +1328,7 @@ static irqreturn_t stm32_mdma_irq_handler(int irq, void *devid)
>   		return IRQ_NONE;
>   	}
>   	id = __ffs(status);
> -
>   	chan = &dmadev->chan[id];
> -	if (!chan) {
> -		dev_warn(mdma2dev(dmadev), "MDMA channel not initialized\n");
> -		return IRQ_NONE;
> -	}
>   
>   	/* Handle interrupt for the channel */
>   	spin_lock(&chan->vchan.lock);

Thanks for your patch,

Reviewed-by: Amelie Delaunay <amelie.delaunay@foss.st.com>