[PATCH v3] iommu/riscv: prevent NULL deref in iova_to_phys

[Joerg Roedel]

On Fri, Aug 15, 2025 at 03:12:44PM +0800, XianLiang Huang wrote:
> diff --git a/drivers/iommu/riscv/iommu.c b/drivers/iommu/riscv/iommu.c
> index 2d0d31ba2886..0eae2f4bdc5e 100644
> --- a/drivers/iommu/riscv/iommu.c
> +++ b/drivers/iommu/riscv/iommu.c
> @@ -1283,7 +1283,7 @@ static phys_addr_t riscv_iommu_iova_to_phys(struct iommu_domain *iommu_domain,
>  	unsigned long *ptr;
>  
>  	ptr = riscv_iommu_pte_fetch(domain, iova, &pte_size);
> -	if (_io_pte_none(*ptr) || !_io_pte_present(*ptr))
> +	if (!ptr)
>  		return 0;

Zero is usually not an invalid physical address, or is it on RISC-V?

-Joerg