diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c
index 3104bf9e684a4dfd1eed25110a468bdfd56f0ab3..bc65815d7bc15e40e965b091ed45979b557c10b9 100644
--- a/src/lxc/lxc_driver.c
+++ b/src/lxc/lxc_driver.c
@@ -5025,13 +5025,14 @@ static int lxcDomainAttachDeviceFlags(virDomainPtr dom,
     }
 
     if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
-        if (virDomainDefCompatibleDevice(vm->def, dev) < 0)
-            goto cleanup;
-
         /* Make a copy for updated domain. */
         vmdef = virDomainObjCopyPersistentDef(vm, caps, driver->xmlopt);
         if (!vmdef)
             goto cleanup;
+
+        if (virDomainDefCompatibleDevice(vmdef, dev) < 0)
+            goto cleanup;
+
         if ((ret = lxcDomainAttachDeviceConfig(vmdef, dev)) < 0)
             goto cleanup;
     }
@@ -5151,13 +5152,14 @@ static int lxcDomainUpdateDeviceFlags(virDomainPtr dom,
     }
 
     if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
-        if (virDomainDefCompatibleDevice(vm->def, dev) < 0)
-            goto cleanup;
-
         /* Make a copy for updated domain. */
         vmdef = virDomainObjCopyPersistentDef(vm, caps, driver->xmlopt);
         if (!vmdef)
             goto cleanup;
+
+        if (virDomainDefCompatibleDevice(vmdef, dev) < 0)
+            goto cleanup;
+
         if ((ret = lxcDomainUpdateDeviceConfig(vmdef, dev)) < 0)
             goto cleanup;
     }
@@ -5261,14 +5263,14 @@ static int lxcDomainDetachDeviceFlags(virDomainPtr dom,
     }
 
     if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
-        if (virDomainDefCompatibleDevice(vm->def, dev) < 0)
-            goto cleanup;
-
         /* Make a copy for updated domain. */
         vmdef = virDomainObjCopyPersistentDef(vm, caps, driver->xmlopt);
         if (!vmdef)
             goto cleanup;
 
+        if (virDomainDefCompatibleDevice(vmdef, dev) < 0)
+            goto cleanup;
+
         if ((ret = lxcDomainDetachDeviceConfig(vmdef, dev)) < 0)
             goto cleanup;
     }
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index fdc3549775e579ba7c1cbe6ff63d09a769c64610..1d90a206758ca07f65e8832b5f93f5b8c9f4dbd1 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -6972,13 +6972,14 @@ static int qemuDomainAttachDeviceFlags(virDomainPtr dom, const char *xml,
         goto cleanup;
 
     if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
-        if (virDomainDefCompatibleDevice(vm->def, dev) < 0)
-            goto endjob;
-
         /* Make a copy for updated domain. */
         vmdef = virDomainObjCopyPersistentDef(vm, caps, driver->xmlopt);
         if (!vmdef)
             goto endjob;
+
+        if (virDomainDefCompatibleDevice(vmdef, dev) < 0)
+            goto endjob;
+
         if ((ret = qemuDomainAttachDeviceConfig(qemuCaps, vmdef, dev)) < 0)
             goto endjob;
     }
@@ -7115,14 +7116,14 @@ static int qemuDomainUpdateDeviceFlags(virDomainPtr dom,
         goto cleanup;
 
     if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
-        if (virDomainDefCompatibleDevice(vm->def, dev) < 0)
-            goto endjob;
-
         /* Make a copy for updated domain. */
         vmdef = virDomainObjCopyPersistentDef(vm, caps, driver->xmlopt);
         if (!vmdef)
             goto endjob;
 
+        if (virDomainDefCompatibleDevice(vmdef, dev) < 0)
+            goto endjob;
+
         if ((ret = qemuDomainUpdateDeviceConfig(qemuCaps, vmdef, dev)) < 0)
             goto endjob;
     }
@@ -7254,13 +7255,14 @@ static int qemuDomainDetachDeviceFlags(virDomainPtr dom, const char *xml,
         goto cleanup;
 
     if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
-        if (virDomainDefCompatibleDevice(vm->def, dev) < 0)
-            goto endjob;
-
         /* Make a copy for updated domain. */
         vmdef = virDomainObjCopyPersistentDef(vm, caps, driver->xmlopt);
         if (!vmdef)
             goto endjob;
+
+        if (virDomainDefCompatibleDevice(vmdef, dev) < 0)
+            goto endjob;
+
         if ((ret = qemuDomainDetachDeviceConfig(vmdef, dev)) < 0)
             goto endjob;
     }