Re: [PATCH] dmaengine: qcom: hidma: fix autosuspend cleanup during teardown
Frank Li <[email protected]>
| Newsgroups | org.kernel.vger.linux-arm-msm,org.infradead.lists.linux-arm-kernel,org.kernel.vger.dmaengine,org.kernel.vger.linux-kernel,org.kernel.vger.stable |
|---|---|
| Message-ID | <an9pMnafob9F-Ry_@lizhi-Precision-Tower-5810> |
On Sat, Aug 08, 2026 at 07:25:51PM +0800, Guangshuo Li wrote:
> hidma_probe() calls pm_runtime_use_autosuspend(), but neither the probe
> failure path nor hidma_remove() calls the matching
> pm_runtime_dont_use_autosuspend() before disabling runtime PM.
>
> If the autosuspend delay is set to a negative value while autosuspend
> is enabled, the runtime PM core increments usage_count to prevent
> runtime suspend. Without calling pm_runtime_dont_use_autosuspend()
> during teardown, this reference is not dropped and usage_count remains
> unbalanced.
>
> Add the missing pm_runtime_dont_use_autosuspend() calls to both the
> probe failure and remove paths before disabling runtime PM.
>
> This issue was found by manual code inspection.
I seen many similar patches to fix similar problem for difference DMA
engineer driver.
Please use devm_runtime_pm_enable() to fix it.
Frank
>
> Fixes: 67a2003e0607 ("dmaengine: add Qualcomm Technologies HIDMA channel driver")
> Cc: [email protected]
> Signed-off-by: Guangshuo Li <[email protected]>
> ---
> drivers/dma/qcom/hidma.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/dma/qcom/hidma.c b/drivers/dma/qcom/hidma.c
> index c939635be21d..78fd765c81e4 100644
> --- a/drivers/dma/qcom/hidma.c
> +++ b/drivers/dma/qcom/hidma.c
> @@ -893,6 +893,7 @@ static int hidma_probe(struct platform_device *pdev)
> hidma_free(dmadev);
> bailout:
> pm_runtime_put_sync(&pdev->dev);
> + pm_runtime_dont_use_autosuspend(&pdev->dev);
> pm_runtime_disable(&pdev->dev);
> return rc;
> }
> @@ -930,6 +931,7 @@ static void hidma_remove(struct platform_device *pdev)
>
> dev_info(&pdev->dev, "HI-DMA engine removed\n");
> pm_runtime_put_sync_suspend(&pdev->dev);
> + pm_runtime_dont_use_autosuspend(&pdev->dev);
> pm_runtime_disable(&pdev->dev);
> }
>
> --
> 2.43.0
>