Comment 17 for bug 470490

Preliminary documentation added to <https://wiki.ubuntu.com/KarmicKoala/ReleaseNotes#GRUB%20menu.lst:%20install%20the%20maintainer%27s%20version%20vs.%20keep%20the%20local%20version>:

If you have previously modified the {{{menu.lst}}} bootloader configuration for GRUB, either by hand or with a tool such as {{{kgrubeditor}}}, you may be asked on upgrade whether you wish to keep your local version of the menu.lst or install the package maintainer's version. This question is asked because such changes cannot be merged automatically with 100% reliability, and care is taken to not overwrite the user's manually edited bootloader configuration without warning.

However, if you choose to "keep the local version currently installed," your system will not be set up to boot from any newly-installed kernels. '''Manual action is required on your part to ensure that your system is running the current, security-supported kernel after upgrade.''' If you have local changes to your bootloader config that you want to keep, it is recommended that you follow these steps:

 * Choose "keep the local version currently installed" at the prompt.
 * Open {{{/boot/grub/menu.lst}}} with a text editor (e.g., {{{sudo gedit /boot/grub/menu.lst}}}).
 * Apply any changes you've made to the kernel boot options to the commented variables (e.g., {{{groot}}}, {{{kopt}}}, {{{defoptions}}}) above.

 * Move any manually-added boot options for other operating systems so that they are above the line {{{
### BEGIN AUTOMAGIC KERNELS LIST
}}} or below the line {{{
### END DEBIAN AUTOMAGIC KERNELS LIST
}}}
 * Save the file, and run {{{sudo update-grub}}} from the commandline.
 * Choose "install the package maintainer's version".

For example, if you added an option `i915.modeset=0` to the "kernel" line:

{{{
kernel /vmlinuz-2.6.31-14-generic root=UUID=0e7... ro quiet splash i915.modeset=0
}}}

then add this option to {{{kopt}}}:

{{{
# kopt=root=UUID=0e7... ro i915.modeset=0
}}}

An updated version of the {{{grub}}} package will include information about this problem in the help screen for the {{{menu.lst}}} prompt. (Bug:470490)

N.B. This last line is not yet settled; still discussing whether it's worth an SRU, since the only place we can put a warning is in the extended 'help'.