RE: [PATCH v5 04/13] iommufd/hw_pagetable: Enforce invalidation op on vIOMMU-based hwpt_nested

30 Oct 2024


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From: Jason Gunthorpe jgg@nvidia.com
Sent: Wednesday, October 30, 2024 12:05 AM
On Tue, Oct 29, 2024 at 08:22:43AM +0000, Tian, Kevin wrote:
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From: Nicolin Chen nicolinc@nvidia.com
Sent: Saturday, October 26, 2024 7:51 AM
@@ -302,7 +302,9 @@ iommufd_viommu_alloc_hwpt_nested(struct
iommufd_viommu *viommu, u32 flags,
   }
   hwpt->domain->owner = viommu->iommu_dev->ops;

if (WARN_ON_ONCE(hwpt->domain->type !=

IOMMU_DOMAIN_NESTED)) {

if (WARN_ON_ONCE(hwpt->domain->type !=

IOMMU_DOMAIN_NESTED ||

	 (!viommu->ops->cache_invalidate &&


	  !hwpt->domain->ops->cache_invalidate_user))) {

rc = -EINVAL;
goto out_abort;
}

According to patch5, cache invalidate in viommu only uses
viommu->ops->cache_invalidate. Is here intended to allow
nested hwpt created via viommu to still support the old
method?
I think that is reasonable?
Yes, just want to confirm.
Reviewed-by: Kevin Tian kevin.tian@intel.com

    