Comment 9 for bug 1858376

While investigating this bug, another issue was discovered: The list of vmlinuz and initrd files is larger than it should be. The actual list should contain 10 entries, but it actually contains 17 entries.

(The 10 entries are computed as follows: there are 3 vmlinuz files and there are 3 initrd files, all for the same kernel version, 5.3.0-26. Therefore there are 9 possible combinations (3x3=9) of these files the user could select. Finally, there is one vmlinuz and initrd file combination for version 5.3.0-18 from the original ISO. Therefore, there should be 9 + 1 = 10 possible kernel rows the user could chose from, not 16 + 1 = 17).

Cubic's algorithm that matches vmlinuz and initrd files, to list on the Boot Kernels tab, ends up adding more entries than are necessary.

One contributor to this issue is that, in Ubuntu 19.04, after an `apt update`, multiple simlinks are created, pointing to the same vmlinuz or initrd files. For example "vmlinuz" and "vmlinuz.old" both point to "vmlinuz-5.3.0-26-generic", and "initrd.img" and ""initrd.img.old" both point to "initrd.img-5.3.0-26-generic".