Re: [PATCH v2 2/7] ASoC: sprd: Replace dma_request_slave_channel() by dma_request_chan()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] sprd: leak of -EPROBE_DEFER to userspace in ioctl paths
--

commit 27b9b3ffed70e1a1411a3993c1e469b1c18205a6
Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

ASoC: sprd: Replace dma_request_slave_channel() by dma_request_chan()

This commit replaces the deprecated dma_request_slave_channel() function
with dma_request_chan() in the Spreadtrum ALSA SoC driver. It also updates
the error handling to propagate all possible errors returned by the new
function back to the caller.

> diff --git a/sound/soc/sprd/sprd-pcm-compress.c b/sound/soc/sprd/sprd-pcm-compress.c
> index e5249924b54d9..f394121d417a3 100644
> --- a/sound/soc/sprd/sprd-pcm-compress.c
> +++ b/sound/soc/sprd/sprd-pcm-compress.c
[ ... ]
> @@ -153,12 +154,12 @@ static int sprd_platform_compr_dma_config(struct snd_soc_component *component,
>  		return -EINVAL;
>  	}
>  
> -	dma->chan = dma_request_slave_channel(dev,
> -					      dma_params->chan_name[channel]);
> -	if (!dma->chan) {
> +	chan = dma_request_chan(dev, dma_params->chan_name[channel]);
> +	if (IS_ERR(chan)) {
>  		dev_err(dev, "failed to request dma channel\n");
> -		return -ENODEV;
> +		return PTR_ERR(chan);

[Severity: Medium]
Since sprd_platform_compr_dma_config() is called during the ALSA
SNDRV_COMPRESS_SET_PARAMS ioctl path, could this propagate -EPROBE_DEFER
directly to userspace if dma_request_chan() defers probing? Returning
internal kernel errors like -EPROBE_DEFER to userspace can confuse user
applications as it violates UAPI error semantics.

>  	}
> +	dma->chan = chan;
>  
>  	sgt = sg = kzalloc_objs(*sg, sg_num);
>  	if (!sg) {
> diff --git a/sound/soc/sprd/sprd-pcm-dma.c b/sound/soc/sprd/sprd-pcm-dma.c
> index 2d5ffbe17e814..2a89dc7616bf7 100644
> --- a/sound/soc/sprd/sprd-pcm-dma.c
> +++ b/sound/soc/sprd/sprd-pcm-dma.c
[ ... ]
> @@ -170,15 +170,16 @@ static int sprd_pcm_request_dma_channel(struct snd_soc_component *component,
>  
>  	for (i = 0; i < channels; i++) {
>  		struct sprd_pcm_dma_data *data = &dma_private->data[i];
> +		struct dma_chan *chan;
>  
> -		data->chan = dma_request_slave_channel(dev,
> -						       dma_params->chan_name[i]);
> -		if (!data->chan) {
> +		chan = dma_request_chan(dev, dma_params->chan_name[i]);
> +		if (IS_ERR(chan)) {
>  			dev_err(dev, "failed to request dma channel:%s\n",
>  				dma_params->chan_name[i]);
>  			sprd_pcm_release_dma_channel(substream);
> -			return -ENODEV;
> +			return PTR_ERR(chan);

[Severity: Medium]
Similarly, sprd_pcm_request_dma_channel() is invoked during the
SNDRV_PCM_IOCTL_HW_PARAMS ioctl path. Does returning PTR_ERR(chan) here also
risk leaking -EPROBE_DEFER to userspace if the DMA channel is not yet
available?

>  		}
> +		data->chan = chan;
>  	}
>  
>  	return 0;

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260918113727.1898998-1-andriy.shevchenko@linux.intel.com?part=2