diff --git a/src/bhyve/bhyve_domain.c b/src/bhyve/bhyve_domain.c
index 4924766030468b03fd6d7bf2104cf7767442df55..9a21cde452e355a5a8067a56f2e65d75449db9c4 100644
--- a/src/bhyve/bhyve_domain.c
+++ b/src/bhyve/bhyve_domain.c
@@ -277,5 +277,6 @@ virXMLNamespace virBhyveDriverDomainXMLNamespace = {
     .parse = bhyveDomainDefNamespaceParse,
     .free = bhyveDomainDefNamespaceFree,
     .format = bhyveDomainDefNamespaceFormatXML,
+    .prefix = "bhyve",
     .href = bhyveDomainDefNamespaceHref,
 };
diff --git a/src/lxc/lxc_domain.c b/src/lxc/lxc_domain.c
index df847b4fcaf74306a2a734f4192078dabea11e3c..b61c17280455e3188d5f174322a23daf87aad708 100644
--- a/src/lxc/lxc_domain.c
+++ b/src/lxc/lxc_domain.c
@@ -321,6 +321,7 @@ virXMLNamespace virLXCDriverDomainXMLNamespace = {
     .parse = lxcDomainDefNamespaceParse,
     .free = lxcDomainDefNamespaceFree,
     .format = lxcDomainDefNamespaceFormatXML,
+    .prefix = "lxc",
     .href = lxcDomainDefNamespaceHref,
 };
 
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index f92b483bcfcf4fc5e14814f8e509027572c5a9d6..bd124b824c8eb02c693ed3dd1fb4b0eccc2e3a36 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -3732,6 +3732,7 @@ virXMLNamespace virQEMUDriverDomainXMLNamespace = {
     .parse = qemuDomainDefNamespaceParse,
     .free = qemuDomainDefNamespaceFree,
     .format = qemuDomainDefNamespaceFormatXML,
+    .prefix = "qemu",
     .href = qemuDomainDefNamespaceHref,
 };
 
diff --git a/src/test/test_driver.c b/src/test/test_driver.c
index 6dbd76d4499b88159b67e04d8752f0e20ce4b472..adda3ac4c06ad5cbe02e81e3bfbfb1d521551760 100644
--- a/src/test/test_driver.c
+++ b/src/test/test_driver.c
@@ -429,6 +429,7 @@ testDriverNew(void)
     virXMLNamespace ns = {
         .parse = testDomainDefNamespaceParse,
         .free = testDomainDefNamespaceFree,
+        .prefix = "test",
     };
     virDomainDefParserConfig config = {
         .features = VIR_DOMAIN_DEF_FEATURE_MEMORY_HOTPLUG |
diff --git a/src/vmx/vmx.c b/src/vmx/vmx.c
index 0f7c2d5f20f6972d28acf0a7aa2a0b31c20173af..ac24e765d45d4f680dff65ba6a147b03e0ea52c2 100644
--- a/src/vmx/vmx.c
+++ b/src/vmx/vmx.c
@@ -607,6 +607,7 @@ static virXMLNamespace virVMXDomainXMLNamespace = {
     .parse = NULL,
     .free = virVMXDomainDefNamespaceFree,
     .format = virVMXDomainDefNamespaceFormatXML,
+    .prefix = "vmware",
     .href = virVMXDomainDefNamespaceHref,
 };