From b411dc88b46890400a2e1ba0aa8650e00f738c23 Mon Sep 17 00:00:00 2001
From: Michael Chang <mchang@suse.com>
Date: Thu, 19 Jul 2012 18:43:55 +0800
Subject: [PATCH] fix menu in xen host server

References: bnc#771689, bnc#757895
Patch-Mainline: no

When system is configred as "Xen Virtual Machines Host Server", the
grub2 menu is not well organized. We could see some issues on it.

 - Many duplicated xen entries generated by links to xen hypervisor
 - Non bootable kernel entries trying to boot xen kernel natively
 - The -dbg xen hypervisor takes precedence over release version

This patch fixes above three issues.

v2:
References: bnc#877040
Create only hypervisor pointed by /boot/xen.gz symlink to not clutter
the menu with multiple versions and also not include -dbg. Use custom.cfg
if you need any other custom entries.

---
 util/grub-mkconfig_lib.in   |    5 +++++
 util/grub.d/10_linux.in     |   12 ++++++++++--
 util/grub.d/20_linux_xen.in |    6 ++++--
 3 files changed, 19 insertions(+), 4 deletions(-)

--- a/util/grub.d/20_linux_xen.in
+++ b/util/grub.d/20_linux_xen.in
@@ -26,6 +26,12 @@
 export TEXTDOMAIN=@PACKAGE@
 export TEXTDOMAINDIR="@localedir@"
 
+if [ ! -e /proc/xen/xsd_port -a -e /proc/xen ]; then
+# we're running on xen domU guest
+# prevent setting up nested virt on HVM or PV domU guest
+    exit 0
+fi
+
 CLASS="--class gnu-linux --class gnu --class os --class xen"
 
 if [ "x${GRUB_DISTRIBUTOR}" = "x" ] ; then
@@ -213,10 +219,18 @@
     esac
 }
 
-xen_list=
-for i in /boot/xen*; do
-    if grub_file_is_not_garbage "$i" && file_is_not_xen_garbage "$i" ; then xen_list="$xen_list $i" ; fi
-done
+# bnc#877040 - Duplicate entries for boot menu created
+# only create /boot/xen.gz symlink boot entry
+if test -L /boot/xen.gz; then
+    xen_list=`readlink -f /boot/xen.gz`
+else
+    # bnc#757895 - Grub2 menu items incorrect when "Xen Virtual Machines Host Server" selected
+    # wildcard expasion with correct suffix (.gz) for not generating many duplicated menu entries
+    xen_list=
+    for i in /boot/xen*.gz; do
+	if grub_file_is_not_garbage "$i" && file_is_not_sym "$i" ; then xen_list="$xen_list $i" ; fi
+    done
+fi
 prepare_boot_cache=
 boot_device_id=
 
--- a/util/grub.d/10_linux.in
+++ b/util/grub.d/10_linux.in
@@ -258,6 +258,40 @@
     fi
   done
 
+  # try to get the kernel config if $linux is a symlink
+  if test -z "${config}" ; then
+    lnk_version=`basename \`readlink -f $linux\` | sed -e "s,^[^0-9]*-,,g"`
+    if (test -n ${lnk_version} && test -e "${dirname}/config-${lnk_version}") ; then
+      config="${dirname}/config-${lnk_version}"
+    fi
+  fi
+
+  # check if we are in xen domU
+  if [ ! -e /proc/xen/xsd_port -a -e /proc/xen ]; then
+    # we're running on xen domU guest
+    dmi=/sys/class/dmi/id
+    if [ -r "${dmi}/product_name" -a -r "${dmi}/sys_vendor" ]; then
+      product_name=`cat ${dmi}/product_name`
+      sys_vendor=`cat ${dmi}/sys_vendor`
+      if test "${sys_vendor}" = "Xen" -a "${product_name}" = "HVM domU"; then
+        # xen HVM guest
+        xen_pv_domU=false
+      fi
+    fi
+  else
+    # we're running on baremetal or xen dom0
+    xen_pv_domU=false
+  fi
+
+  if test "$xen_pv_domU" = "false" ; then
+    # prevent xen kernel without pv_opt support from booting
+    if (grep -qx "CONFIG_XEN=y" "${config}" 2> /dev/null && ! grep -qx "CONFIG_PARAVIRT=y" "${config}" 2> /dev/null); then
+      echo "Skip xenlinux kernel $linux" >&2
+      list=`echo $list | tr ' ' '\n' | grep -vx $linux | tr '\n' ' '`
+      continue
+    fi
+  fi
+
   initramfs=
   if test -n "${config}" ; then
       initramfs=`grep CONFIG_INITRAMFS_SOURCE= "${config}" | cut -f2 -d= | tr -d \"`
