Re: [PATCH 1/2] dmaengine: zynqmp_dma: fix race between runtime PM and device removal

[Pandey, Radhey Shyam]

> In zynqmp_dma_remove(), runtime PM was disabled only after checking
> state and doing a manual suspend. This can race with runtime PM in the
> remove/unbind (rmmod) path.
>
> Disable runtime PM first, then suspend only if the device is not already
> suspended. To prevent any further runtime PM transitions.
>
> Fixes: 72dd8b2914b5 ("dmaengine: zynqmp_dma: Add shutdown operation support")
> Co-developed-by: Prasanna Kumar T S M <ptsm@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Prasanna Kumar T S M <ptsm@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Golla Nagendra <nagendra.golla@xxxxxxx>

Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxx>
Thanks!
> ---
>   drivers/dma/xilinx/zynqmp_dma.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
> index 1402331f7ef5..26f097db593d 100644
> --- a/drivers/dma/xilinx/zynqmp_dma.c
> +++ b/drivers/dma/xilinx/zynqmp_dma.c
> @@ -1188,9 +1188,9 @@ static void zynqmp_dma_remove(struct platform_device *pdev)
>   	dma_async_device_unregister(&zdev->common);
>   
>   	zynqmp_dma_chan_remove(zdev->chan);
> -	if (pm_runtime_active(zdev->dev))
> -		zynqmp_dma_runtime_suspend(zdev->dev);
>   	pm_runtime_disable(zdev->dev);
> +	if (!pm_runtime_status_suspended(zdev->dev))
> +		zynqmp_dma_runtime_suspend(zdev->dev);
>   }
>   
>   static const struct of_device_id zynqmp_dma_of_match[] = {