Re: [PATCH 7/7] iommu/amd: Fully decode all combinations of alloc_paging_flags

[Jason Gunthorpe <jgg@nvidia.com>]

On Tue, Jan 07, 2025 at 04:17:59PM +0530, Vasant Hegde wrote:
> > @@ -2375,24 +2375,25 @@ amd_iommu_domain_alloc_paging_flags(struct device *dev, u32 flags,
> >  	if ((flags & ~supported_flags) || user_data)
                  ^^^^^^

> >  		return ERR_PTR(-EOPNOTSUPP);
> >  
> > -	/* Allocate domain with v2 page table if IOMMU supports PASID. */
> > -	if (flags & IOMMU_HWPT_ALLOC_PASID) {
> > +	switch (flags &
> > +		(IOMMU_HWPT_ALLOC_PASID | IOMMU_HWPT_ALLOC_DIRTY_TRACKING)) {
> 
> Better use supported_flags. Otherwise patch looks good to me.
> With that

For now we can just delete it since we already checked that flags
can't be outside that range.

Maybe when new flags are added it will need to come back someday

-       switch (flags &
-               (IOMMU_HWPT_ALLOC_PASID | IOMMU_HWPT_ALLOC_DIRTY_TRACKING)) {
+       switch (flags & supported_flags) {

Thanks,
Jason