diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index d84d0327ad..f05a6cb225 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -2270,13 +2270,12 @@ virDomainDiskGetDriver(const virDomainDiskDef *def)
 }
 
 
-int
+void
 virDomainDiskSetDriver(virDomainDiskDefPtr def, const char *name)
 {
     char *tmp = g_strdup(name);
     g_free(def->driverName);
     def->driverName = tmp;
-    return 0;
 }
 
 
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 9fc5841457..4cd6bcd01d 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -3043,8 +3043,7 @@ const char *virDomainDiskGetSource(virDomainDiskDef const *def);
 void virDomainDiskSetSource(virDomainDiskDefPtr def, const char *src);
 void virDomainDiskEmptySource(virDomainDiskDefPtr def);
 const char *virDomainDiskGetDriver(const virDomainDiskDef *def);
-int virDomainDiskSetDriver(virDomainDiskDefPtr def, const char *name)
-    G_GNUC_WARN_UNUSED_RESULT;
+void virDomainDiskSetDriver(virDomainDiskDefPtr def, const char *name);
 int virDomainDiskGetFormat(virDomainDiskDefPtr def);
 void virDomainDiskSetFormat(virDomainDiskDefPtr def, int format);
 virDomainControllerDefPtr
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c
index 43d23565f1..383f2295a2 100644
--- a/src/libxl/libxl_conf.c
+++ b/src/libxl/libxl_conf.c
@@ -1237,7 +1237,7 @@ libxlUpdateDiskDef(virDomainDiskDefPtr l_disk, libxl_device_disk *x_disk)
         break;
     }
     if (driver)
-        ignore_value(virDomainDiskSetDriver(l_disk, driver));
+        virDomainDiskSetDriver(l_disk, driver);
 }
 
 int
diff --git a/src/libxl/libxl_domain.c b/src/libxl/libxl_domain.c
index a3f362a0c8..3669b358f6 100644
--- a/src/libxl/libxl_domain.c
+++ b/src/libxl/libxl_domain.c
@@ -361,9 +361,8 @@ libxlDomainDeviceDefPostParse(virDomainDeviceDefPtr dev,
 
         /* for network-based disks, set 'qemu' as the default driver */
         if (actual_type == VIR_STORAGE_TYPE_NETWORK) {
-            if (!virDomainDiskGetDriver(disk) &&
-                virDomainDiskSetDriver(disk, "qemu") < 0)
-                return -1;
+            if (!virDomainDiskGetDriver(disk))
+                virDomainDiskSetDriver(disk, "qemu");
         }
 
         /* xl.cfg default format is raw. See xl-disk-configuration(5) */
diff --git a/src/libxl/libxl_driver.c b/src/libxl/libxl_driver.c
index 00a74dcb49..2195ecf47b 100644
--- a/src/libxl/libxl_driver.c
+++ b/src/libxl/libxl_driver.c
@@ -4086,8 +4086,7 @@ libxlDomainUpdateDeviceConfig(virDomainDefPtr vmdef, virDomainDeviceDefPtr dev)
             virDomainDiskSetSource(orig, virDomainDiskGetSource(disk));
             virDomainDiskSetType(orig, virDomainDiskGetType(disk));
             virDomainDiskSetFormat(orig, virDomainDiskGetFormat(disk));
-            if (virDomainDiskSetDriver(orig, virDomainDiskGetDriver(disk)) < 0)
-                return -1;
+            virDomainDiskSetDriver(orig, virDomainDiskGetDriver(disk));
             break;
         default:
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
diff --git a/src/libxl/xen_xl.c b/src/libxl/xen_xl.c
index d195f866c5..ed0ce77db4 100644
--- a/src/libxl/xen_xl.c
+++ b/src/libxl/xen_xl.c
@@ -725,8 +725,7 @@ xenParseXLDisk(virConfPtr conf, virDomainDefPtr def)
             disk->removable = libxldisk->removable;
 
             if (libxldisk->is_cdrom) {
-                if (virDomainDiskSetDriver(disk, "qemu") < 0)
-                    goto fail;
+                virDomainDiskSetDriver(disk, "qemu");
 
                 virDomainDiskSetType(disk, VIR_STORAGE_TYPE_FILE);
                 disk->device = VIR_DOMAIN_DISK_DEVICE_CDROM;
@@ -772,21 +771,18 @@ xenParseXLDisk(virConfPtr conf, virDomainDefPtr def)
                 switch (libxldisk->backend) {
                 case LIBXL_DISK_BACKEND_QDISK:
                 case LIBXL_DISK_BACKEND_UNKNOWN:
-                    if (virDomainDiskSetDriver(disk, "qemu") < 0)
-                        goto fail;
+                    virDomainDiskSetDriver(disk, "qemu");
                     if (virDomainDiskGetType(disk) == VIR_STORAGE_TYPE_NONE)
                         virDomainDiskSetType(disk, VIR_STORAGE_TYPE_FILE);
                     break;
 
                 case LIBXL_DISK_BACKEND_TAP:
-                    if (virDomainDiskSetDriver(disk, "tap") < 0)
-                        goto fail;
+                    virDomainDiskSetDriver(disk, "tap");
                     virDomainDiskSetType(disk, VIR_STORAGE_TYPE_FILE);
                     break;
 
                 case LIBXL_DISK_BACKEND_PHY:
-                    if (virDomainDiskSetDriver(disk, "phy") < 0)
-                        goto fail;
+                    virDomainDiskSetDriver(disk, "phy");
                     virDomainDiskSetType(disk, VIR_STORAGE_TYPE_BLOCK);
                     break;
                 default:
diff --git a/src/libxl/xen_xm.c b/src/libxl/xen_xm.c
index 283ed1ee8b..3e81c9ef0d 100644
--- a/src/libxl/xen_xm.c
+++ b/src/libxl/xen_xm.c
@@ -165,10 +165,7 @@ xenParseXMDisk(char *entry, int hvm)
             len = tmp - src;
             tmp = g_strndup(src, len);
 
-            if (virDomainDiskSetDriver(disk, tmp) < 0) {
-                VIR_FREE(tmp);
-                goto error;
-            }
+            virDomainDiskSetDriver(disk, tmp);
             VIR_FREE(tmp);
 
             /* Strip the prefix we found off the source file name */
@@ -208,9 +205,8 @@ xenParseXMDisk(char *entry, int hvm)
     }
 
     /* No source, or driver name, so fix to phy: */
-    if (!virDomainDiskGetDriver(disk) &&
-        virDomainDiskSetDriver(disk, "phy") < 0)
-        goto error;
+    if (!virDomainDiskGetDriver(disk))
+        virDomainDiskSetDriver(disk, "phy");
 
     /* phy: type indicates a block device */
     virDomainDiskSetType(disk,
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 02b5e7422c..70896ad80e 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -5086,9 +5086,8 @@ qemuDomainDeviceDiskDefPostParse(virDomainDiskDefPtr disk,
                                  unsigned int parseFlags)
 {
     /* set default disk types and drivers */
-    if (!virDomainDiskGetDriver(disk) &&
-        virDomainDiskSetDriver(disk, "qemu") < 0)
-        return -1;
+    if (!virDomainDiskGetDriver(disk))
+        virDomainDiskSetDriver(disk, "qemu");
 
     /* default disk format for drives */
     if (virDomainDiskGetFormat(disk) == VIR_STORAGE_FILE_NONE &&
diff --git a/src/vz/vz_sdk.c b/src/vz/vz_sdk.c
index 6a0ab5c862..cdd3f61ee1 100644
--- a/src/vz/vz_sdk.c
+++ b/src/vz/vz_sdk.c
@@ -698,8 +698,7 @@ prlsdkGetDiskInfo(vzDriverPtr driver,
             VIR_FREE(disk->serial);
     }
 
-    if (virDomainDiskSetDriver(disk, "vz") < 0)
-        goto cleanup;
+    virDomainDiskSetDriver(disk, "vz");
 
     if (disk->device == VIR_DOMAIN_DISK_DEVICE_DISK) {
         pret = PrlVmDevHd_GetDiskSize(prldisk, &size);