Bug#555985: Missing xen support, regression from grub1

[Goswin von Brederlow]

Package: grub-pc
Version: 1.96+20090725-1
Severity: normal

Hi,

grub2 does not add entries for xen hypervisor and kernels. After
reading the docs I managed to create an entry manually like this:

menuentry "Xen 3.4, kernel 2.6.31.5 git 20091113" {
    insmod ext2
    set root=(hd0,1)
    search --no-floppy --fs-uuid --set 69c9f9d8-4772-4391-9111-e66ef6b49ac6
    multiboot /xen-3.4-amd64.gz dom0_mem=512M
    module /vmlinuz-2.6.31.5-xen-00513-g47dfde5 nomodeset
    module /initrd.gz
}

I would suggest adding new variables to /etc/default/grub:

# Options for the xen hypervisor and kernel command line
#GRUB_CMDLINE_XEN_HYPERVISOR="dom0_mem=512M"
GRUB_CMDLINE_XEN_KERNEL="nomodeset"

and this in 10_linux ($3 == /boot/xen-3.4-amd64.gz for example):

xen_linux_entry ()
{
  cat << EOF
menuentry "$1" {
EOF
  prepare_grub_to_access_device ${GRUB_DEVICE_BOOT} | sed -e "s/^/\t/"
  cat << EOF
        multiboot  ${rel_dirname}/"$3" ${GRUB_CMDLINE_XEN_HYPERVISOR}
        module     ${rel_dirname}/${basename} root=${linux_root_device_thisversion} ro $2
EOF
  if test -n "${initrd}" ; then
    cat << EOF
        module     ${rel_dirname}/${initrd}
EOF
  fi
  cat << EOF
}
EOF
}


Now the tricky part is when to call that. There can be multiple
hypervisors installed (/boot/xen-<x>.<y>-<flavour>.gz). Also multiple
kernels (/boot/vmlinuz-*xen*). Xen kernels can also be for domU or
dom0+domU. In dom0 adding a domU kernel makes no sense. On the other
hand in domU adding non-xen kernels makes little sense.

So maybe /etc/defaults/grub should have a variable listing the pattern
for images that should be added:

# Add a menuentry for every linux kernel:
GRUB_PATTERN_LINUX="vmlinu[xz]*"

# Add a menuentry for every xen kernel:
GRUB_PATTERN_XEN="vmlinu[xz]*xen*"

# Add a menuentry only for dom0 xen kernel:
#GRUB_PATTERN_XEN="vmlinu[xz]*xen0*"

# Add a menuentry only for domU xen kernel:
#GRUB_PATTERN_XEN="vmlinu[xz]*xenu*"

and 10_linux could then use those to build its list of images.
How does that sound? Should I prepare a patch along those lines?

MfG
	Goswin


-- System Information:
Debian Release: squeeze/sid
  APT prefers unstable-i386
  APT policy: (1001, 'unstable-i386'), (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.29.4-frosties-2 (SMP w/4 CPU cores)
Locale: LANG=C, LC_CTYPE=de_DE (charmap=ISO-8859-1)
Shell: /bin/sh linked to /bin/bash

Versions of packages grub-pc depends on:
ii  debconf [debconf-2.0]    1.5.27          Debian configuration management sy
ii  grub-common              1.96+20090725-1 GRand Unified Bootloader, version 
ii  libc6                    2.10.1-2        GNU C Library: Shared libraries
ii  ucf                      3.0018          Update Configuration File: preserv

grub-pc recommends no packages.

Versions of packages grub-pc suggests:
pn  desktop-base                  <none>     (no description available)
ii  genisoimage                   9:1.1.9-1  Creates ISO-9660 CD-ROM filesystem
pn  os-prober                     <none>     (no description available)

-- debconf information excluded