Comment 3 for bug 569201

Very easy to replicate.

Extended partition must exist.

Logical partition must exist (in the extended partition, obviously.)

Unallocated space must exist inside the extended partition and before the logical partition (ie between the start of the extended partition and the start of the logical partition it contains.)

Install to any partition using the 'specify partitions manually' option (while retaining the above.) *Target partition must not contain a previous ext filesystem or the partitioner won't have a reason to play with the partition tables*

The ubiquity installer will move the start of the extended partition to (a couple of sectors prior to) the start of the logical partition.

The installer is more than happy to move the start of the extended partition hundreds of gigabytes even, it doesn't care.

So what if I left that space at the start of my extended partition there for a reason? Say I wanted to put a partition there later. Too bad. Even if there are already 3 primary partitions, the installer moves the unallocated space outside! So you can forget about 4K alignment, or Windows 7 1024K alignment, it'll screw that up too.

The problem is even apparent during the manual partition setup page.

Either the installer has problems reading a partitioning system where the extended partition has unallocated space prior to the first logical partition, or it mistakenly *corrects* this configuration.

Either way this is a problem.