dmaengine: sprd: Fix runtime PM reference leak in probe

[PATCH] dmaengine: sprd: Fix runtime PM reference leak in probe

Posted by Ruoyu Wang 1 month, 2 weeks ago

pm_runtime_get_sync() increments a device's usage counter even when it
fails. sprd_dma_probe() currently jumps directly to controller clock
cleanup on that error, bypassing both pm_runtime_put_noidle() and
pm_runtime_disable(). This can happen if the preceding unchecked
pm_runtime_set_active() fails and the following runtime-resume attempt
also returns an error.

Enter the existing runtime-PM unwind path instead. This drops the
reference without idling the partially initialized device, disables
runtime PM, and then releases the controller clocks. The success path
and propagated error code are unchanged.

This issue was found by a static analysis checker and confirmed by manual
source review.

Fixes: 9b3b8171f7f4 ("dmaengine: sprd: Add Spreadtrum DMA driver")
Signed-off-by: Ruoyu Wang <ruoyuw560@gmail.com>
---
 drivers/dma/sprd-dma.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
index 087fea3af2e411..19b32a23c882de 100644
--- a/drivers/dma/sprd-dma.c
+++ b/drivers/dma/sprd-dma.c
@@ -1212,7 +1212,7 @@ static int sprd_dma_probe(struct platform_device *pdev)
 
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (ret < 0)
-		goto err_rpm;
+		goto err_register;
 
 	ret = dma_async_device_register(&sdev->dma_dev);
 	if (ret < 0) {
@@ -1234,7 +1234,6 @@ static int sprd_dma_probe(struct platform_device *pdev)
 err_register:
 	pm_runtime_put_noidle(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
-err_rpm:
 	sprd_dma_disable(sdev);
 	return ret;
 }
-- 
2.51.0

Re: [PATCH] dmaengine: sprd: Fix runtime PM reference leak in probe

Posted by Vinod Koul 3 weeks, 4 days ago

On Thu, 13 Aug 2026 23:31:49 +0800, Ruoyu Wang wrote:
> pm_runtime_get_sync() increments a device's usage counter even when it
> fails. sprd_dma_probe() currently jumps directly to controller clock
> cleanup on that error, bypassing both pm_runtime_put_noidle() and
> pm_runtime_disable(). This can happen if the preceding unchecked
> pm_runtime_set_active() fails and the following runtime-resume attempt
> also returns an error.
> 
> [...]

Applied, thanks!

[1/1] dmaengine: sprd: Fix runtime PM reference leak in probe
      commit: a7df136ec529ee49a789c5029bc37b98b0d4bedd

Best regards,
-- 
~Vinod

Re: [PATCH] dmaengine: sprd: Fix runtime PM reference leak in probe

Posted by Frank Li 1 month, 1 week ago

On Thu, Aug 13, 2026 at 11:31:49PM +0800, Ruoyu Wang wrote:
> pm_runtime_get_sync() increments a device's usage counter even when it
> fails. sprd_dma_probe() currently jumps directly to controller clock
> cleanup on that error, bypassing both pm_runtime_put_noidle() and
> pm_runtime_disable(). This can happen if the preceding unchecked
> pm_runtime_set_active() fails and the following runtime-resume attempt
> also returns an error.
>
> Enter the existing runtime-PM unwind path instead. This drops the
> reference without idling the partially initialized device, disables
> runtime PM, and then releases the controller clocks. The success path
> and propagated error code are unchanged.
>
> This issue was found by a static analysis checker and confirmed by manual
> source review.
>
> Fixes: 9b3b8171f7f4 ("dmaengine: sprd: Add Spreadtrum DMA driver")
> Signed-off-by: Ruoyu Wang <ruoyuw560@gmail.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/dma/sprd-dma.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
> index 087fea3af2e411..19b32a23c882de 100644
> --- a/drivers/dma/sprd-dma.c
> +++ b/drivers/dma/sprd-dma.c
> @@ -1212,7 +1212,7 @@ static int sprd_dma_probe(struct platform_device *pdev)
>
>  	ret = pm_runtime_get_sync(&pdev->dev);
>  	if (ret < 0)
> -		goto err_rpm;
> +		goto err_register;
>
>  	ret = dma_async_device_register(&sdev->dma_dev);
>  	if (ret < 0) {
> @@ -1234,7 +1234,6 @@ static int sprd_dma_probe(struct platform_device *pdev)
>  err_register:
>  	pm_runtime_put_noidle(&pdev->dev);
>  	pm_runtime_disable(&pdev->dev);
> -err_rpm:
>  	sprd_dma_disable(sdev);
>  	return ret;
>  }
> --
> 2.51.0
>

Re: [PATCH] dmaengine: sprd: Fix runtime PM reference leak in probe

Posted by Baolin Wang 1 month, 2 weeks ago


On 8/13/26 11:31 PM, Ruoyu Wang wrote:
> pm_runtime_get_sync() increments a device's usage counter even when it
> fails. sprd_dma_probe() currently jumps directly to controller clock
> cleanup on that error, bypassing both pm_runtime_put_noidle() and
> pm_runtime_disable(). This can happen if the preceding unchecked
> pm_runtime_set_active() fails and the following runtime-resume attempt
> also returns an error.
> 
> Enter the existing runtime-PM unwind path instead. This drops the
> reference without idling the partially initialized device, disables
> runtime PM, and then releases the controller clocks. The success path
> and propagated error code are unchanged.
> 
> This issue was found by a static analysis checker and confirmed by manual
> source review.
> 
> Fixes: 9b3b8171f7f4 ("dmaengine: sprd: Add Spreadtrum DMA driver")
> Signed-off-by: Ruoyu Wang <ruoyuw560@gmail.com>
> ---

LGTM. Thanks.
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>

>   drivers/dma/sprd-dma.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
> index 087fea3af2e411..19b32a23c882de 100644
> --- a/drivers/dma/sprd-dma.c
> +++ b/drivers/dma/sprd-dma.c
> @@ -1212,7 +1212,7 @@ static int sprd_dma_probe(struct platform_device *pdev)
>   
>   	ret = pm_runtime_get_sync(&pdev->dev);
>   	if (ret < 0)
> -		goto err_rpm;
> +		goto err_register;
>   
>   	ret = dma_async_device_register(&sdev->dma_dev);
>   	if (ret < 0) {
> @@ -1234,7 +1234,6 @@ static int sprd_dma_probe(struct platform_device *pdev)
>   err_register:
>   	pm_runtime_put_noidle(&pdev->dev);
>   	pm_runtime_disable(&pdev->dev);
> -err_rpm:
>   	sprd_dma_disable(sdev);
>   	return ret;
>   }