casper 1.340.1 breaks previous persistency
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
casper (Ubuntu) |
Fix Released
|
Medium
|
Andy Whitcroft | ||
Trusty |
Fix Released
|
High
|
Andy Whitcroft | ||
Vivid |
Triaged
|
Medium
|
Andy Whitcroft | ||
Wily |
Fix Released
|
Medium
|
Andy Whitcroft |
Bug Description
Likely scenario (unless I missed a crucial piece of information):
- User has a working persistency file (or partition), with an Ubuntu 14.04.2 ISO
- User upgrades to an Ubuntu 14.04.3 ISO, and boots it with the same persistency settings
Likely result:
- It appears to the user that the persistent data is lost
Cause:
- In casper 1.340, persistency data is stored in the root of the persistency partition
- In casper 1.340.1, persistency data is stored in the /upper directory of the persistency partition
Actual issue I faced:
- I maintain a personal, custom Kubuntu ISO. Nothing too fancy: it is just the regular Kubuntu ISO, with many additional packages (digikam, darktable, etc.; all from the official Ubuntu repository). I regularly update my ISO by chrooting in the uncompressed squashfs and running aptitude there. I have a script to rebuild the ISO afterwards.
- Today's update brought me casper 1.340.1, which broke my persistency as described above
- Additionally, since I'm still running Linux 3.16, casper.log also featured a magnificent red herring:
> mount: mounting /cow on /root failed: Invalid argument
It took me a while to understand that the mount was actually successful (the first mount with the workdir option fails and emits the message, the second mount succeeds silently).
My solution was quite simply:
- Boot without persistency
- Mount the persistent partition
- Empty the /upper directory that had been created when I first booted with casper 1.340.1
- Move data from the root of the persistent partition to the /upper directory
- Reboot with persistency
I'm not sure all users of the persistency feature will be as adept at fixing their persistency partition. It is surprising to see such an incompatible change introduced in a minor update of an LTS version.
Related branches
Changed in casper (Ubuntu): | |
assignee: | nobody → Andy Whitcroft (apw) |
tags: | added: trusty |
Changed in casper (Ubuntu): | |
milestone: | none → ubuntu-15.08 |
status: | Triaged → In Progress |
Changed in casper (Ubuntu Trusty): | |
milestone: | none → ubuntu-14.04.3 |
Changed in casper (Ubuntu Trusty): | |
importance: | Undecided → High |
Changed in casper (Ubuntu Vivid): | |
status: | New → Triaged |
importance: | Undecided → Medium |
Adding tag "regression-update" as per comment #7 of bug #1401620