Re: [PATCH RFC 04/10] intel_iommu: Second Stage Access Dirty bit support

[Peter Xu]

Hi, Joao,

On Thu, Apr 28, 2022 at 10:13:45PM +0100, Joao Martins wrote:
> +/* Get the content of a spte located in @base_addr[@index] */
> +static uint64_t vtd_set_slpte(dma_addr_t base_addr, uint32_t index,
> +                              uint64_t slpte)
> +{
> +
> +    if (dma_memory_write(&address_space_memory,
> +                         base_addr + index * sizeof(slpte), &slpte,
> +                         sizeof(slpte), MEMTXATTRS_UNSPECIFIED)) {
> +        slpte = (uint64_t)-1;
> +        return slpte;
> +    }
> +
> +    return vtd_get_slpte(base_addr, index);
> +}

Could I ask when the write succeeded, why need to read slpte again?

Thanks,

-- 
Peter Xu