Re: [PATCH] media: rkvdec: Fix a NULL vs IS_ERR() bug in probe()

[Detlev Casanova <detlev.casanova@collabora.com>]

Hi Dan,

On Wednesday, 25 June 2025 11:23:10 EDT Dan Carpenter wrote:
> The iommu_paging_domain_alloc() function doesn't return NULL on error it
> returns error pointers.  Update the check and then set ->empty_domain to
> NULL because the rest of the driver assumes it can be NULL.
> 
> Fixes: ff8c5622f9f7 ("media: rkvdec: Restore iommu addresses on errors")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
>  drivers/staging/media/rkvdec/rkvdec.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/media/rkvdec/rkvdec.c
> b/drivers/staging/media/rkvdec/rkvdec.c index d707088ec0dc..1b7f27e4d961
> 100644
> --- a/drivers/staging/media/rkvdec/rkvdec.c
> +++ b/drivers/staging/media/rkvdec/rkvdec.c
> @@ -1162,8 +1162,10 @@ static int rkvdec_probe(struct platform_device *pdev)
> if (iommu_get_domain_for_dev(&pdev->dev)) {
>  		rkvdec->empty_domain = 
iommu_paging_domain_alloc(rkvdec->dev);
> 
> -		if (!rkvdec->empty_domain)
> +		if (IS_ERR(rkvdec->empty_domain)) {
> +			rkvdec->empty_domain = NULL;
>  			dev_warn(rkvdec->dev, "cannot alloc new 
empty domain\n");
> +		}
>  	}
> 
>  	vb2_dma_contig_set_max_seg_size(&pdev->dev, DMA_BIT_MASK(32));

Thank you for finding this one. I tested it on rock 5b and all is good. 

Tested-by: Detlev Casanova <detlev.casanova@collabora.com>

Regards,
Detlev.