Re: [PATCH] iommu/ipmmu-vmsa: Check for error num after setting mask

[Joerg Roedel <joro@8bytes.org>]

Adding more potential reviewers.

On Thu, Jan 06, 2022 at 10:43:02AM +0800, Jiasheng Jiang wrote:
> Because of the possible failure of the dma_supported(), the
> dma_set_mask_and_coherent() may return error num.
> Therefore, it should be better to check it and return the error if
> fails.
> 
> Fixes: 1c894225bf5b ("iommu/ipmmu-vmsa: IPMMU device is 40-bit bus master")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  drivers/iommu/ipmmu-vmsa.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index aaa6a4d59057..7df5da44a004 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -1003,7 +1003,9 @@ static int ipmmu_probe(struct platform_device *pdev)
>  	bitmap_zero(mmu->ctx, IPMMU_CTX_MAX);
>  	mmu->features = of_device_get_match_data(&pdev->dev);
>  	memset(mmu->utlb_ctx, IPMMU_CTX_INVALID, mmu->features->num_utlbs);
> -	dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40));
> +	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40));
> +	if (ret)
> +		return ret;
>  
>  	/* Map I/O memory and request IRQ. */
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -- 
> 2.25.1