RE: [PATCH 09/14] iommufd: Add iommufd_device_replace()

From: Jason Gunthorpe jgg@nvidia.com Sent: Saturday, February 25, 2023 8:28 AM

+static struct iommufd_hw_pagetable * +iommufd_device_do_replace_locked(struct iommufd_device *idev,

• 		 struct iommufd_hw_pagetable *hwpt)
  

+{

• struct iommufd_hw_pagetable *old_hwpt;
• int rc;
• lockdep_assert_held(&idev->igroup->lock);
• /* Try to upgrade the domain we have */
• if (idev->enforce_cache_coherency) {

• rc = iommufd_hw_pagetable_enforce_cc(hwpt);
  

• if (rc)
  

• 	return ERR_PTR(-EINVAL);
  

• }
• rc = iommufd_device_setup_msi(idev, hwpt);
• if (rc)

• return ERR_PTR(rc);
  

• old_hwpt = idev->igroup->hwpt;
• if (hwpt->ioas != old_hwpt->ioas) {

• rc = iopt_table_enforce_group_resv_regions(
  

• 	&hwpt->ioas->iopt, idev->igroup->group, NULL);
  

• if (rc)
  

• 	return ERR_PTR(rc);
  

• }

This is inconsistent with the earlier cleanup in the attach path where setup_msi/enforce_group_resv_region are done only once per group (if that is the right thing to do).