Re: [PATCH v5 2/5] media: imx-jpeg: Reset slot data pointers when free data

[Nicolas Dufresne <nicolas@ndufresne.ca>]

Le vendredi 18 avril 2025 à 15:08 +0800, ming.qian@oss.nxp.com a écrit :
> From: Ming Qian <ming.qian@oss.nxp.com>
> 
> To make the function mxc_jpeg_alloc_slot_data() and
> mxc_jpeg_free_slot_data() safe to be called multiple times. Ensure that
> the slot data pointers are reset to NULL and handles are set to 0 after
> freeing the coherent memory.

Perhaps:

   media: imx-jpeg: Reset slot data pointers when freed


   Ensure that the slot data pointers are reset to NULL and handles are
   set to 0 after freeing the coherent memory. This makes he function
   mxc_jpeg_alloc_slot_data() and mxc_jpeg_free_slot_data() safe to be
   called multiple times.

> 
> Fixes: 2db16c6ed72c ("media: imx-jpeg: Add V4L2 driver for i.MX8 JPEG Encoder/Decoder")
> Signed-off-by: Ming Qian <ming.qian@oss.nxp.com>
> ---
> v5
> - Make a single patch to reset the slot data pointers when free data
> 
>  drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
> index 2f7ee5dfa93d..b2f7e9ad1885 100644
> --- a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
> +++ b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
> @@ -758,16 +758,22 @@ static void mxc_jpeg_free_slot_data(struct mxc_jpeg_dev *jpeg)
>  	dma_free_coherent(jpeg->dev, sizeof(struct mxc_jpeg_desc),
>  			  jpeg->slot_data.desc,
>  			  jpeg->slot_data.desc_handle);
> +	jpeg->slot_data.desc = NULL;
> +	jpeg->slot_data.desc_handle = 0;
>  
>  	/* free descriptor for encoder configuration phase / decoder DHT */
>  	dma_free_coherent(jpeg->dev, sizeof(struct mxc_jpeg_desc),
>  			  jpeg->slot_data.cfg_desc,
>  			  jpeg->slot_data.cfg_desc_handle);
> +	jpeg->slot_data.cfg_desc_handle = 0;
> +	jpeg->slot_data.cfg_desc = NULL;
>  
>  	/* free configuration stream */
>  	dma_free_coherent(jpeg->dev, MXC_JPEG_MAX_CFG_STREAM,
>  			  jpeg->slot_data.cfg_stream_vaddr,
>  			  jpeg->slot_data.cfg_stream_handle);
> +	jpeg->slot_data.cfg_stream_vaddr = NULL;
> +	jpeg->slot_data.cfg_stream_handle = 0;
>  
>  	jpeg->slot_data.used = false;
>  }

Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>