Re: [PATCH v6 07/13] iommufd: Allow pt_id to carry viommu_id for IOMMU_HWPT_ALLOC

[Nicolin Chen <nicolinc@nvidia.com>]

On Thu, Oct 31, 2024 at 10:14:59AM -0300, Jason Gunthorpe wrote:
> On Wed, Oct 30, 2024 at 02:34:33PM -0700, Nicolin Chen wrote:
> > +static struct iommufd_hwpt_nested *
> > +iommufd_viommu_alloc_hwpt_nested(struct iommufd_viommu *viommu, u32 flags,
> > +				 const struct iommu_user_data *user_data)
> > +{
> > +	struct iommufd_hwpt_nested *hwpt_nested;
> > +	struct iommufd_hw_pagetable *hwpt;
> > +	int rc;
> > +
> > +	if ((flags & ~IOMMU_HWPT_FAULT_ID_VALID) || !user_data->len)
> > +		return ERR_PTR(-EOPNOTSUPP);
> 
> Now that flags exists we are expecting the driver to validate it, so
> this check on flags should be dropped?
> 
> Or we go back to hiding FAULT_ID_VALID from the driver (and keep the flags)?

If we plan to fix the HWPT-based side, I think we should just drop
this check on flags here.

Thanks
Nicolin