iommu/vt-d: Fix bind svm with multiple devices

If multiple devices try to bind to the same mm/PASID, we need to
set up first level PASID entries for all the devices. The current
code does not consider this case which results in failed DMA for
devices after the first bind.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reported-by: Mike Campin <mike.campin@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel-svm.c

@@ -374,6 +374,21 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_
 		}
 
 		list_add_tail(&svm->list, &global_svm_list);
+	} else {
+		/*
+		 * Binding a new device with existing PASID, need to setup
+		 * the PASID entry.
+		 */
+		spin_lock(&iommu->lock);
+		ret = intel_pasid_setup_first_level(iommu, dev,
+						mm ? mm->pgd : init_mm.pgd,
+						svm->pasid, FLPT_DEFAULT_DID,
+						mm ? 0 : PASID_FLAG_SUPERVISOR_MODE);
+		spin_unlock(&iommu->lock);
+		if (ret) {
+			kfree(sdev);
+			goto out;
+		}
 	}
 	list_add_rcu(&sdev->list, &svm->devs);