On Sat, Apr 06, 2024 at 02:09:34PM +0800, Baolu Lu wrote: > On 4/3/24 7:59 PM, Jason Gunthorpe wrote: > > On Wed, Apr 03, 2024 at 09:15:12AM +0800, Lu Baolu wrote: > > > + /* A bond already exists, just take a reference`. */ > > > + handle = iommu_attach_handle_get(group, iommu_mm->pasid); > > > + if (handle) { > > > + mutex_unlock(&iommu_sva_lock); > > > + return handle; > > > } > > At least in this context this is not enough we need to ensure that the > > domain on the PASID is actually an SVA domain and it was installed by > > this mechanism, not an iommufd domain for instance. > > > > ie you probably need a type field in the iommu_attach_handle to tell > > what the priv is. > > > > Otherwise this seems like a great idea! > > Yes, you are right. For the SVA case, I will add the following changes. > The IOMMUFD path will also need such enhancement. I will update it in > the next version. The only use for this is the PRI callbacks right? Maybe instead of adding a handle type let's just check domain->iopf_handler ? Ie SVA will pass &ommu_sva_iopf_handler as its "type" Jason