Re: [PATCH] crypto: stm32/cryp: fix autosuspend cleanup during teardown

[Maxime MERE <maxime.mere@foss.st.com>]

On 8/8/26 11:36, Guangshuo Li wrote:
> stm32_cryp_probe() calls pm_runtime_use_autosuspend(), but neither the
> probe failure path nor stm32_cryp_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.
> 
> Fixes: 65f9aa36ee47 ("crypto: stm32/cryp - Add power management support")
> Cc: stable@vger.kernel.org
> Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
> ---
>   drivers/crypto/stm32/stm32-cryp.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/crypto/stm32/stm32-cryp.c b/drivers/crypto/stm32/stm32-cryp.c
> index b79877099942..74f6e329b1fa 100644
> --- a/drivers/crypto/stm32/stm32-cryp.c
> +++ b/drivers/crypto/stm32/stm32-cryp.c
> @@ -2691,6 +2691,7 @@ static int stm32_cryp_probe(struct platform_device *pdev)
>   		dma_release_channel(cryp->dma_lch_out);
>   err_dma:
>   err_rst:
> +	pm_runtime_dont_use_autosuspend(dev);
>   	pm_runtime_disable(dev);
>   	pm_runtime_put_noidle(dev);
>   
> @@ -2722,6 +2723,7 @@ static void stm32_cryp_remove(struct platform_device *pdev)
>   	if (cryp->dma_lch_out)
>   		dma_release_channel(cryp->dma_lch_out);
>   
> +	pm_runtime_dont_use_autosuspend(cryp->dev);
>   	pm_runtime_disable(cryp->dev);
>   	pm_runtime_put_noidle(cryp->dev);
>   

Reviewed-by: Maxime Méré <maxime.mere@foss.st.com>

Cheers,

Maxime