diff --git a/src/xenconfig/xen_xl.c b/src/xenconfig/xen_xl.c
index be194e3..f3e8b55 100644
--- a/src/xenconfig/xen_xl.c
+++ b/src/xenconfig/xen_xl.c
@@ -587,9 +587,8 @@ xenFormatXLDisk(virConfValuePtr list, virDomainDiskDefPtr disk)
     int format = virDomainDiskGetFormat(disk);
     const char *driver = virDomainDiskGetDriver(disk);
 
-    /* target */
-    virBufferAsprintf(&buf, "%s,", src);
     /* format */
+    virBufferAddLit(&buf, "format=");
     switch (format) {
         case VIR_STORAGE_FILE_RAW:
             virBufferAddLit(&buf, "raw,");
@@ -609,31 +608,37 @@ xenFormatXLDisk(virConfValuePtr list, virDomainDiskDefPtr disk)
     }
 
     /* device */
-    virBufferAdd(&buf, disk->dst, -1);
-
-    virBufferAddLit(&buf, ",");
+    virBufferAsprintf(&buf, "vdev=%s,", disk->dst);
 
+    /* access */
+    virBufferAddLit(&buf, "access=");
     if (disk->src->readonly)
-        virBufferAddLit(&buf, "r,");
+        virBufferAddLit(&buf, "ro,");
     else if (disk->src->shared)
         virBufferAddLit(&buf, "!,");
     else
-        virBufferAddLit(&buf, "w,");
+        virBufferAddLit(&buf, "rw,");
     if (disk->transient) {
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                        _("transient disks not supported yet"));
         goto cleanup;
     }
 
+    /* backendtype */
+    virBufferAddLit(&buf, "backendtype=");
     if (STREQ_NULLABLE(driver, "qemu"))
-        virBufferAddLit(&buf, "backendtype=qdisk");
+        virBufferAddLit(&buf, "qdisk,");
     else if (STREQ_NULLABLE(driver, "tap"))
-        virBufferAddLit(&buf, "backendtype=tap");
+        virBufferAddLit(&buf, "tap,");
     else if (STREQ_NULLABLE(driver, "phy"))
-        virBufferAddLit(&buf, "backendtype=phy");
+        virBufferAddLit(&buf, "phy,");
 
+    /* devtype */
     if (disk->device == VIR_DOMAIN_DISK_DEVICE_CDROM)
-        virBufferAddLit(&buf, ",devtype=cdrom");
+        virBufferAddLit(&buf, "devtype=cdrom,");
+
+    /* target */
+    virBufferAsprintf(&buf, "target=%s", src);
 
     if (virBufferCheckError(&buf) < 0)
         goto cleanup;
diff --git a/tests/xlconfigdata/test-disk-positional-parms-full.cfg b/tests/xlconfigdata/test-disk-positional-parms-full.cfg
new file mode 100644
index 0000000..026e451
--- /dev/null
+++ b/tests/xlconfigdata/test-disk-positional-parms-full.cfg
@@ -0,0 +1,26 @@
+name = "XenGuest2"
+uuid = "c7a5fdb2-cdaf-9455-926a-d65c16db1809"
+maxmem = 579
+memory = 394
+vcpus = 1
+pae = 1
+acpi = 1
+apic = 1
+hap = 0
+viridian = 0
+rtc_timeoffset = 0
+localtime = 0
+on_poweroff = "destroy"
+on_reboot = "restart"
+on_crash = "restart"
+device_model = "/usr/lib/xen/bin/qemu-dm"
+sdl = 0
+vnc = 1
+vncunused = 1
+vnclisten = "127.0.0.1"
+vif = [ "mac=00:16:3e:66:92:9c,bridge=xenbr1,script=vif-bridge,model=e1000" ]
+parallel = "none"
+serial = "none"
+builder = "hvm"
+boot = "d"
+disk = [ "/dev/HostVG/XenGuest2,raw,hda,rw,backendtype=phy", "/var/lib/libvirt/images/XenGuest2-home,qcow2,hdb,rw", "/root/boot.iso,raw,hdc,ro,devtype=cdrom" ]
diff --git a/tests/xlconfigdata/test-disk-positional-parms-full.xml b/tests/xlconfigdata/test-disk-positional-parms-full.xml
new file mode 100644
index 0000000..49f6dbe
--- /dev/null
+++ b/tests/xlconfigdata/test-disk-positional-parms-full.xml
@@ -0,0 +1,54 @@
+<domain type='xen'>
+  <name>XenGuest2</name>
+  <uuid>c7a5fdb2-cdaf-9455-926a-d65c16db1809</uuid>
+  <memory unit='KiB'>592896</memory>
+  <currentMemory unit='KiB'>403456</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64' machine='xenfv'>hvm</type>
+    <loader type='rom'>/usr/lib/xen/boot/hvmloader</loader>
+    <boot dev='cdrom'/>
+  </os>
+  <features>
+    <acpi/>
+    <apic/>
+    <pae/>
+  </features>
+  <clock offset='variable' adjustment='0' basis='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>restart</on_crash>
+  <devices>
+    <emulator>/usr/lib/xen/bin/qemu-dm</emulator>
+    <disk type='block' device='disk'>
+      <driver name='phy' type='raw'/>
+      <source dev='/dev/HostVG/XenGuest2'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <disk type='file' device='disk'>
+      <driver name='qemu' type='qcow2'/>
+      <source file='/var/lib/libvirt/images/XenGuest2-home'/>
+      <target dev='hdb' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
+    </disk>
+    <disk type='file' device='cdrom'>
+      <driver name='qemu' type='raw'/>
+      <source file='/root/boot.iso'/>
+      <target dev='hdc' bus='ide'/>
+      <readonly/>
+      <address type='drive' controller='0' bus='1' target='0' unit='0'/>
+    </disk>
+    <interface type='bridge'>
+      <mac address='00:16:3e:66:92:9c'/>
+      <source bridge='xenbr1'/>
+      <script path='vif-bridge'/>
+      <model type='e1000'/>
+    </interface>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <graphics type='vnc' port='-1' autoport='yes' listen='127.0.0.1'>
+      <listen type='address' address='127.0.0.1'/>
+    </graphics>
+  </devices>
+</domain>
diff --git a/tests/xlconfigdata/test-disk-positional-parms-partial.cfg b/tests/xlconfigdata/test-disk-positional-parms-partial.cfg
new file mode 100644
index 0000000..0591037
--- /dev/null
+++ b/tests/xlconfigdata/test-disk-positional-parms-partial.cfg
@@ -0,0 +1,26 @@
+name = "XenGuest2"
+uuid = "c7a5fdb2-cdaf-9455-926a-d65c16db1809"
+maxmem = 579
+memory = 394
+vcpus = 1
+pae = 1
+acpi = 1
+apic = 1
+hap = 0
+viridian = 0
+rtc_timeoffset = 0
+localtime = 0
+on_poweroff = "destroy"
+on_reboot = "restart"
+on_crash = "restart"
+device_model = "/usr/lib/xen/bin/qemu-dm"
+sdl = 0
+vnc = 1
+vncunused = 1
+vnclisten = "127.0.0.1"
+vif = [ "mac=00:16:3e:66:92:9c,bridge=xenbr1,script=vif-bridge,model=e1000" ]
+parallel = "none"
+serial = "none"
+builder = "hvm"
+boot = "d"
+disk = [ "/dev/HostVG/XenGuest2,,hda,,backendtype=phy", "/var/lib/libvirt/images/XenGuest2-home,,hdb,,", "/root/boot.iso,,hdc,,devtype=cdrom" ]
diff --git a/tests/xlconfigdata/test-disk-positional-parms-partial.xml b/tests/xlconfigdata/test-disk-positional-parms-partial.xml
new file mode 100644
index 0000000..3268295
--- /dev/null
+++ b/tests/xlconfigdata/test-disk-positional-parms-partial.xml
@@ -0,0 +1,54 @@
+<domain type='xen'>
+  <name>XenGuest2</name>
+  <uuid>c7a5fdb2-cdaf-9455-926a-d65c16db1809</uuid>
+  <memory unit='KiB'>592896</memory>
+  <currentMemory unit='KiB'>403456</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64' machine='xenfv'>hvm</type>
+    <loader type='rom'>/usr/lib/xen/boot/hvmloader</loader>
+    <boot dev='cdrom'/>
+  </os>
+  <features>
+    <acpi/>
+    <apic/>
+    <pae/>
+  </features>
+  <clock offset='variable' adjustment='0' basis='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>restart</on_crash>
+  <devices>
+    <emulator>/usr/lib/xen/bin/qemu-dm</emulator>
+    <disk type='block' device='disk'>
+      <driver name='phy' type='raw'/>
+      <source dev='/dev/HostVG/XenGuest2'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <disk type='file' device='disk'>
+      <driver name='qemu' type='raw'/>
+      <source file='/var/lib/libvirt/images/XenGuest2-home'/>
+      <target dev='hdb' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
+    </disk>
+    <disk type='file' device='cdrom'>
+      <driver name='qemu' type='raw'/>
+      <source file='/root/boot.iso'/>
+      <target dev='hdc' bus='ide'/>
+      <readonly/>
+      <address type='drive' controller='0' bus='1' target='0' unit='0'/>
+    </disk>
+    <interface type='bridge'>
+      <mac address='00:16:3e:66:92:9c'/>
+      <source bridge='xenbr1'/>
+      <script path='vif-bridge'/>
+      <model type='e1000'/>
+    </interface>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <graphics type='vnc' port='-1' autoport='yes' listen='127.0.0.1'>
+      <listen type='address' address='127.0.0.1'/>
+    </graphics>
+  </devices>
+</domain>
diff --git a/tests/xlconfigdata/test-fullvirt-direct-kernel-boot.cfg b/tests/xlconfigdata/test-fullvirt-direct-kernel-boot.cfg
index 32b08e1..9ebbc89 100644
--- a/tests/xlconfigdata/test-fullvirt-direct-kernel-boot.cfg
+++ b/tests/xlconfigdata/test-fullvirt-direct-kernel-boot.cfg
@@ -27,4 +27,4 @@ kernel = "/tmp/vmlinuz"
 ramdisk = "/tmp/initrd"
 cmdline = "ignore_loglvl"
 boot = "d"
-disk = [ "/dev/HostVG/XenGuest2,raw,hda,w,backendtype=phy", "/root/boot.iso,raw,hdc,r,backendtype=qdisk,devtype=cdrom" ]
+disk = [ "format=raw,vdev=hda,access=rw,backendtype=phy,target=/dev/HostVG/XenGuest2", "format=raw,vdev=hdc,access=ro,backendtype=qdisk,devtype=cdrom,target=/root/boot.iso" ]
diff --git a/tests/xlconfigdata/test-fullvirt-multiusb.cfg b/tests/xlconfigdata/test-fullvirt-multiusb.cfg
index d0482a8..097de88 100755
--- a/tests/xlconfigdata/test-fullvirt-multiusb.cfg
+++ b/tests/xlconfigdata/test-fullvirt-multiusb.cfg
@@ -24,6 +24,6 @@ parallel = "none"
 serial = "none"
 builder = "hvm"
 boot = "d"
-disk = [ "/dev/HostVG/XenGuest2,raw,hda,w,backendtype=phy", "/root/boot.iso,raw,hdc,r,backendtype=qdisk,devtype=cdrom" ]
+disk = [ "format=raw,vdev=hda,access=rw,backendtype=phy,target=/dev/HostVG/XenGuest2", "format=raw,vdev=hdc,access=ro,backendtype=qdisk,devtype=cdrom,target=/root/boot.iso" ]
 usb = 1
 usbdevice = [ "mouse", "tablet" ]
diff --git a/tests/xlconfigdata/test-new-disk.cfg b/tests/xlconfigdata/test-new-disk.cfg
index 9b9fb36..4a5b66e 100644
--- a/tests/xlconfigdata/test-new-disk.cfg
+++ b/tests/xlconfigdata/test-new-disk.cfg
@@ -23,4 +23,4 @@ parallel = "none"
 serial = "none"
 builder = "hvm"
 boot = "d"
-disk = [ "/dev/HostVG/XenGuest2,raw,hda,w,backendtype=phy", "/var/lib/libvirt/images/XenGuest2-home,qcow2,hdb,w,backendtype=qdisk", "/root/boot.iso,raw,hdc,r,backendtype=qdisk,devtype=cdrom" ]
+disk = [ "format=raw,vdev=hda,access=rw,backendtype=phy,target=/dev/HostVG/XenGuest2", "format=qcow2,vdev=hdb,access=rw,backendtype=qdisk,target=/var/lib/libvirt/images/XenGuest2-home", "format=raw,vdev=hdc,access=ro,backendtype=qdisk,devtype=cdrom,target=/root/boot.iso" ]
diff --git a/tests/xlconfigdata/test-paravirt-cmdline.cfg b/tests/xlconfigdata/test-paravirt-cmdline.cfg
index c512a05..e82d900 100644
--- a/tests/xlconfigdata/test-paravirt-cmdline.cfg
+++ b/tests/xlconfigdata/test-paravirt-cmdline.cfg
@@ -11,4 +11,4 @@ vif = [ "mac=00:16:3e:66:92:9c,bridge=xenbr1,script=vif-bridge" ]
 kernel = "/tmp/vmlinuz"
 ramdisk = "/tmp/initrd"
 cmdline = "root=/dev/xvda1 console=hvc0"
-disk = [ "/dev/HostVG/XenGuest2,raw,xvda,w,backendtype=qdisk" ]
+disk = [ "format=raw,vdev=xvda,access=rw,backendtype=qdisk,target=/dev/HostVG/XenGuest2" ]
diff --git a/tests/xlconfigdata/test-paravirt-maxvcpus.cfg b/tests/xlconfigdata/test-paravirt-maxvcpus.cfg
index d506b75..8316774 100644
--- a/tests/xlconfigdata/test-paravirt-maxvcpus.cfg
+++ b/tests/xlconfigdata/test-paravirt-maxvcpus.cfg
@@ -10,4 +10,4 @@ on_reboot = "restart"
 on_crash = "preserve"
 vif = [ "mac=5a:36:0e:be:00:09" ]
 bootloader = "/usr/bin/pygrub"
-disk = [ "/var/lib/xen/images/debian/disk.qcow2,qcow2,xvda,w,backendtype=qdisk" ]
+disk = [ "format=qcow2,vdev=xvda,access=rw,backendtype=qdisk,target=/var/lib/xen/images/debian/disk.qcow2" ]
diff --git a/tests/xlconfigdata/test-spice-features.cfg b/tests/xlconfigdata/test-spice-features.cfg
index 152cb27..8c1ca18 100644
--- a/tests/xlconfigdata/test-spice-features.cfg
+++ b/tests/xlconfigdata/test-spice-features.cfg
@@ -19,7 +19,7 @@ parallel = "none"
 serial = "none"
 builder = "hvm"
 boot = "d"
-disk = [ "/dev/HostVG/XenGuest2,raw,hda,w,backendtype=phy", "/root/boot.iso,raw,hdc,r,backendtype=qdisk,devtype=cdrom" ]
+disk = [ "format=raw,vdev=hda,access=rw,backendtype=phy,target=/dev/HostVG/XenGuest2", "format=raw,vdev=hdc,access=ro,backendtype=qdisk,devtype=cdrom,target=/root/boot.iso" ]
 sdl = 0
 vnc = 0
 spice = 1
diff --git a/tests/xlconfigdata/test-spice.cfg b/tests/xlconfigdata/test-spice.cfg
index 1a96114..84b3ae6 100644
--- a/tests/xlconfigdata/test-spice.cfg
+++ b/tests/xlconfigdata/test-spice.cfg
@@ -19,7 +19,7 @@ parallel = "none"
 serial = "none"
 builder = "hvm"
 boot = "d"
-disk = [ "/dev/HostVG/XenGuest2,raw,hda,w,backendtype=phy", "/root/boot.iso,raw,hdc,r,backendtype=qdisk,devtype=cdrom" ]
+disk = [ "format=raw,vdev=hda,access=rw,backendtype=phy,target=/dev/HostVG/XenGuest2", "format=raw,vdev=hdc,access=ro,backendtype=qdisk,devtype=cdrom,target=/root/boot.iso" ]
 sdl = 0
 vnc = 0
 spice = 1
diff --git a/tests/xlconfigdata/test-vif-rate.cfg b/tests/xlconfigdata/test-vif-rate.cfg
index c5484dc..44bfa3c 100644
--- a/tests/xlconfigdata/test-vif-rate.cfg
+++ b/tests/xlconfigdata/test-vif-rate.cfg
@@ -23,4 +23,4 @@ parallel = "none"
 serial = "none"
 builder = "hvm"
 boot = "d"
-disk = [ "/dev/HostVG/XenGuest2,raw,hda,w,backendtype=phy", "/var/lib/libvirt/images/XenGuest2-home,qcow2,hdb,w,backendtype=qdisk", "/root/boot.iso,raw,hdc,r,backendtype=qdisk,devtype=cdrom" ]
+disk = [ "format=raw,vdev=hda,access=rw,backendtype=phy,target=/dev/HostVG/XenGuest2", "format=qcow2,vdev=hdb,access=rw,backendtype=qdisk,target=/var/lib/libvirt/images/XenGuest2-home", "format=raw,vdev=hdc,access=ro,backendtype=qdisk,devtype=cdrom,target=/root/boot.iso" ]
diff --git a/tests/xlconfigtest.c b/tests/xlconfigtest.c
index aa53ed8..13b99f2 100644
--- a/tests/xlconfigtest.c
+++ b/tests/xlconfigtest.c
@@ -208,6 +208,8 @@ mymain(void)
 
     DO_TEST("paravirt-maxvcpus");
     DO_TEST("new-disk");
+    DO_TEST_FORMAT("disk-positional-parms-full");
+    DO_TEST_FORMAT("disk-positional-parms-partial");
     DO_TEST("spice");
     DO_TEST("spice-features");
     DO_TEST("vif-rate");
