Re: [PATCH 1/1] dma: ioat: set error code on failures

[Dave Jiang]

On 12/01/2016 12:10 AM, Pan Bian wrote:
> Fix bug https://bugzilla.kernel.org/show_bug.cgi?id=188591. In function
> ioat_dma_self_test(), when the calls to dma_mapping_error() fails, the
> value of return variable err is 0 (indicates no error). As a result, the
> return value may be inconsistent with the execution status. This patch
> fixes the bug by assigning -ENOMEM to err on the error path.
> 
> Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>

Acked-by: Dave Jiang <dave.jiang@xxxxxxxxx>

> ---
>  drivers/dma/ioat/init.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/dma/ioat/init.c b/drivers/dma/ioat/init.c
> index 015f711..32383ef 100644
> --- a/drivers/dma/ioat/init.c
> +++ b/drivers/dma/ioat/init.c
> @@ -340,11 +340,13 @@ static int ioat_dma_self_test(struct ioatdma_device *ioat_dma)
>  	dma_src = dma_map_single(dev, src, IOAT_TEST_SIZE, DMA_TO_DEVICE);
>  	if (dma_mapping_error(dev, dma_src)) {
>  		dev_err(dev, "mapping src buffer failed\n");
> +		err = -ENOMEM;
>  		goto free_resources;
>  	}
>  	dma_dest = dma_map_single(dev, dest, IOAT_TEST_SIZE, DMA_FROM_DEVICE);
>  	if (dma_mapping_error(dev, dma_dest)) {
>  		dev_err(dev, "mapping dest buffer failed\n");
> +		err = -ENOMEM;
>  		goto unmap_src;
>  	}
>  	flags = DMA_PREP_INTERRUPT;
>