diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index 611c22fd52..0519dfc9e7 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -2409,7 +2409,7 @@ static int reassign_device_ownership(
                 ret = iommu_identity_mapping(source, p2m_access_x,
                                              rmrr->base_address,
                                              rmrr->end_address, 0);
-                if ( ret != -ENOENT )
+                if ( ret && ret != -ENOENT )
                     return ret;
             }
     }