Re: [PATCH v6 8/8] iommu/vt-d: Disallow read-only mappings to nest parent domain

[Baolu Lu]

On 2023/10/23 19:15, Liu, Yi L wrote:
> > I would also prefer to introduce is_nested_parent_domain to the user
> > domain allocation patch (patch 7/8). This field should be checked when
> > allocating a nested user domain.
> A ctually, no need. This should be a common check, so iommufd core already
> has the check. So the parent should be a nest parent domain, otherwise already
> returned in iommufd.
>
> +	if (!parent->nest_parent)
> +		return ERR_PTR(-EINVAL);

I know this will not cause errors in the code. But since you are
introducing is_parent property in the vt-d driver. The integrity of the
property should be ensured. In this way, it will make the code more
readable and maintainable.

Best regards,
baolu