lupin merge progress

[ago]

Looks much neater now than my implementation.

Some random thoughts:

1) The partman-auto-loop preseeding requires a disk+partition number.
But the preseed file is generated from within windows (at least when
setup.exe is used), and I do not know any good way to map a windows
drive to a linux device from within windows (some windows expert out
there might correct me on this). A workaround might be to also allow
to preseed some other data to be used to find out the host partition
and the loop file via heuristics.

2) The hosting filesystem will be mostly mounted ro in normal
circumstances, which means that it should be remounted rw, e.g. by
using a /host entry in fstab and by modifying
/etc/init.d/checkroot.sh. I am not sure whether you can change the
fstype when remounting, in which case ntfs-3g has to be installed but
it does not need to be within the initrd (which can use ntfs).

3) Once grub is up, you should be aware of an issue with paths inside
menu.lst, since menu.lst is used by grub4dos (where the kernel will be
in c:/ubuntu/boot/vmlinuz) but menu.lst is generated within ubuntu
where the path to the same file looks different (/boot/vmlinuz). At
the moment this is taken care by
lupin/devel/src/lupin-target/etc/init.d/cpkernel but there is probably
a more elegant way to cope with it.

> Comments welcome! Is it possible to update lupin to make use of this, as
> we discussed a while back?

I can do that but if lupin.postinst is taken care of and initrd can
take a loop argument, there will not be much left of lupin...

What is left, on top of the above, is:

A) fix sendsigs to avoid killing userspace filesystems (I have noticed
you have already submitted a patch)

B) disable hibernation/suspend on loopmounted installations (mjg59
might be able to fix suspend issues, but hibernation should not be
feasible), see lupin/devel/src/lupin-target/DEBIAN/postinst

C) modify sysctl to make the filesystem more robust in case of hard
reboots (those can damage the journal of the nested filesystem). The
settings used at the moment (as suggested by szaka, ntfs-3g author)
are:

vm.dirty_background_ratio=0
vm.dirty_ratio=0
vm.dirty_expire_centisecs=1
vm.dirty_writeback_centisecs=1

D) Patch os-prober and m-a. See
lupin/devel/src/alternate-iso/overlay/var/lib/dpkg/info/load-cdrom.postinst

Other than that lupin should be basically dead.


Ago