Reference: bnc#863821
grub.xen is required to boot PV VMs that use the BTRFS filesystem.
This patch forces the use of grub.xen (instead of using pygrub) for
newer suse distros like SLE12 and openSUSE 13.2.
Index: virt-manager-1.4.3/virtinst/guest.py
===================================================================
--- virt-manager-1.4.3.orig/virtinst/guest.py
+++ virt-manager-1.4.3/virtinst/guest.py
@@ -366,8 +366,20 @@ class Guest(XMLBuilder):
         if (not install and
             self.os.is_xenpv() and
             not self.os.kernel):
-            self.bootloader = "/usr/bin/pygrub"
-            self.os.clear()
+            os_ver = self._get_os_variant()
+            if self.os.arch != 'x86_64' or os_ver.startswith("sles9") or \
+               os_ver.startswith("sles10") or os_ver.startswith("sled10") or \
+               os_ver.startswith("opensuse10") or os_ver.startswith("opensuse11"):
+                self.bootloader = "pygrub"
+                self.os.clear()
+            else:
+                self.installer._install_kernel = "/usr/lib/grub2/x86_64-xen/grub.xen"
+                self.installer._install_initrd = None
+                self.installer.extraargs = None
+                # alter_bootconfig won't update the osxml unless it thinks
+                # we are in an install phase. Add force_update param to call
+                self.installer.alter_bootconfig(self, True, True)
+                logging.info("Using grub.xen to boot guest")
 
         return self.get_xml_config()
 
Index: virt-manager-1.4.3/virtinst/installer.py
===================================================================
--- virt-manager-1.4.3.orig/virtinst/installer.py
+++ virt-manager-1.4.3/virtinst/installer.py
@@ -99,7 +99,7 @@ class Installer(object):
                 break
         return bootorder
 
-    def alter_bootconfig(self, guest, isinstall):
+    def alter_bootconfig(self, guest, isinstall, force_update=False):
         """
         Generate the portion of the guest xml that determines boot devices
         and parameters. (typically the <os></os> block)
@@ -110,7 +110,7 @@ class Installer(object):
                           'post-install' phase.
         @type isinstall: C{bool}
         """
-        if isinstall and not self.has_install_phase():
+        if isinstall and not force_update and not self.has_install_phase():
             return
 
         bootorder = guest.os.bootorder