[Bug 586756] Re: update-grub ignores pvops kernels on Xen domU

[Group_6]

update-grub.old 2011-04-06 17:37:34.198906717 +0200
+++ update-grub 2011-04-06 17:37:20.437907250 +0200
@@ -1382,7 +1382,7 @@

 xenKernels=""
-for ver in `grep -l CONFIG_XEN_PRIVILEGED_GUEST=y /boot/config* | sed -e s%/boot/config-%%`; do
+for ver in `grep -l CONFIG_XEN=y /boot/config* | sed -e s%/boot/config-%%`; do
   # ver is a kernel version
   kern="/boot/vmlinuz-$ver"
   if [ -r $kern ] ; then
@@ -1413,7 +1413,7 @@

 sortedKernels=""
 for kern in $(/bin/ls -1vr /boot | grep -v "dpkg-*" | grep "^vmlinuz-") ; do
- if `echo "$xenKernels" | grep -q "$kern "` || `echo "$kern" | grep -q "xen"`; then
+ if `echo "$xenKernels" | grep -q "$kern"` || `echo "$kern" | grep -q "xen"`; then
                is_xen=1
        else
                is_xen=

** Changed in: grub (Ubuntu)
     Assignee: (unassigned) => Group_6 (basavarajmulagund92)

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to grub in Ubuntu.
https://bugs.launchpad.net/bugs/586756

Title:
  update-grub ignores pvops kernels on Xen domU

Status in grub package in Ubuntu:
  Invalid

Bug description:
  Binary package hint: grub

  Ubuntu 10.04 LTS. But the problem also manifests under 9.10 and 9.04.
  grub 0.97-29ubuntu60

  I am running on a Xen domU.

  update-grub seems to have logic in it to choose Xen/non-Xen kernels on
  Xen-domUs / other systems.

  However this logic seems to be flawed.

  Nowadays, Xen domUs can use "ordinary" kernels because modern kernels
  have pvops included.

  1. update-grub seems to be looking for kernels with the word "xen" in
  their name in order to believe that they will work in a Xen domU. This
  is broken because pvops kernels will work under a Xen domU but will
  not have the word "xen" in their name

  2. update-grub seems to be written on the basis that a kernel will
  either be "Xen" or "non-Xen" and those are mutually exclusive. This is
  broken because "ordinary" kernels with pvops will be suitable for both
  Xen and non-Xen working.

  The upshot is that for me update-grub ignores a perfectly usable
  "ordinary" kernel, which I would rather it recogised and configured
  for me.

  My quick workaround was to fudge update-grub to treat all kernels as
  Xen kernels. This made update-grub recognise the kernel, configure it
  into /boot/grub/menu.lst, and the system was then able to boot
  correctly.

  As that kernel does in fact work fine, but update-grub ignored it,
  this suggests a shortcoming in the behaviour of update-grub.

  The fix I would suggest would have two parts:

  1. Improve the ability of update-grub to recognise Xen-capable
  kernels. This could be done by adding another possibility 'or'-ed with
  existing detections, on the detection of Xen-capable kernels. (Though
  see the second part because if the paradigm is altered it may mean a
  re-write to that part of the program.)

  Take the name of the kernel image, e.g. vmlinuz-2.6.32-3-amd64, then
  take off the "vmlinuz-" from the beginning to leave "2.6.32-3-amd64".
  Store this in a variable "kernelSuffix". Then look for the existence
  of a file "/lib/modules/${kernelSuffix}/kernel/drivers/block/xen-
  blkfront.ko". If this file exists, then you have a kernel which is
  suitable for Xen-domU operation (and probably ALSO non-Xen-domU
  operation).

  2. Considering the Xen/Non-Xen attribute ("is_xen") this either needs
  to have a third option "Either", OR it could be split into two
  attributes "xenDomU" (yes/no or "1"/"") and "nonXenDomU" (yes/no or
  "1"/""). Kernels which are detected as Xen domU suitable by the
  detection of the xen-blkfront.ko kernel module will likely be suitable
  for BOTH Xen-domU operation AND non-Xen-DomU operation, so should be
  considered in both cases of Xen-domU and non-Xen-domU systems.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/grub/+bug/586756/+subscriptions