diff --git a/src/conf/capabilities.c b/src/conf/capabilities.c
index 4478d85f40095ba44d23f73d20c6cc4ae0eccf13..36f97b9b3f6638ac2febb4ba3ec79422676eba8d 100644
--- a/src/conf/capabilities.c
+++ b/src/conf/capabilities.c
@@ -175,6 +175,9 @@ virCapabilitiesFree(virCapsPtr caps) {
     VIR_FREE(caps->host.secModel.doi);
     virCPUDefFree(caps->host.cpu);
 
+    VIR_FREE(caps->defaultDiskDriverName);
+    VIR_FREE(caps->defaultDiskDriverType);
+
     VIR_FREE(caps);
 }
 
diff --git a/src/conf/capabilities.h b/src/conf/capabilities.h
index 9290c826dab0c15b42a322b74f3e01a879d3debc..f676eb8014ca8fa034f362815113d4b8b1d356d0 100644
--- a/src/conf/capabilities.h
+++ b/src/conf/capabilities.h
@@ -123,6 +123,8 @@ struct _virCaps {
     virCapsGuestPtr *guests;
     unsigned char macPrefix[VIR_MAC_PREFIX_BUFLEN];
     unsigned int emulatorRequired : 1;
+    const char *defaultDiskDriverName;
+    const char *defaultDiskDriverType;
     void *(*privateDataAllocFunc)(void);
     void (*privateDataFreeFunc)(void *);
     int (*privateDataXMLFormat)(virBufferPtr, void *);
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index b20ca975e5c1ff5074f3f3989837ded5d1008c77..f3b8cfa3a56b0b8ac539e2669002495bcd1b76d5 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1639,6 +1639,16 @@ virDomainDiskDefParseXML(virCapsPtr caps,
     def->serial = serial;
     serial = NULL;
 
+    if (!def->driverType &&
+        caps->defaultDiskDriverType &&
+        !(def->driverType = strdup(caps->defaultDiskDriverType)))
+        goto no_memory;
+
+    if (!def->driverName &&
+        caps->defaultDiskDriverName &&
+        !(def->driverName = strdup(caps->defaultDiskDriverName)))
+        goto no_memory;
+
     if (def->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE
         && virDomainDiskDefAssignAddress(caps, def) < 0)
         goto error;
@@ -1659,6 +1669,9 @@ cleanup:
 
     return def;
 
+no_memory:
+    virReportOOMError();
+
  error:
     virDomainDiskDefFree(def);
     def = NULL;
@@ -4275,7 +4288,8 @@ static virDomainDefPtr virDomainDefParseXML(virCapsPtr caps,
     if (n && VIR_ALLOC_N(def->disks, n) < 0)
         goto no_memory;
     for (i = 0 ; i < n ; i++) {
-        virDomainDiskDefPtr disk = virDomainDiskDefParseXML(caps, nodes[i],
+        virDomainDiskDefPtr disk = virDomainDiskDefParseXML(caps,
+                                                            nodes[i],
                                                             flags);
         if (!disk)
             goto error;
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index ca87ca80a40fce0619acac9f2e6f19c8f107a72d..2eb254e7d1365f471e8cc49b078222a5cd473456 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -1361,6 +1361,14 @@ qemuCreateCapabilities(virCapsPtr oldcaps,
         return NULL;
     }
 
+    if (driver->allowDiskFormatProbing) {
+        caps->defaultDiskDriverName = NULL;
+        caps->defaultDiskDriverType = NULL;
+    } else {
+        caps->defaultDiskDriverName = "qemu";
+        caps->defaultDiskDriverType = "raw";
+    }
+
     /* Domain XML parser hooks */
     caps->privateDataAllocFunc = qemuDomainObjPrivateAlloc;
     caps->privateDataFreeFunc = qemuDomainObjPrivateFree;