Xenial minimal install: "W: plymouth: The plugin label.so is missing, the selected theme might not work as expected."

[Daniel Richard G.]

[SRU Justification]
All users of ubuntu-text-based plymouth themes get a spurious warning when generating initramfs. This warning is trivially fixable.

[Regression potential]
Only the regression potential of a new binary build. The only change to the code is to bypass this warning message for the 'ubuntu-text' plugin.

[Test case]
1. Install the plymouth-theme-ubuntu-text package.
2. Uninstall/deconfigure all graphical themes (e.g.: apt remove plymouth-theme-ubuntu)
3. Run update-initramfs -u
4. Confirm that a warning message is shown about label.so being missing.
5. Install plymouth from -proposed.
6. Run update-initramfs -u
7. Confirm that no warning message is shown.
8. Boot and confirm that the text theme is shown correctly.

I installed a minimal Xenial system. Whenever the initramfs is regenerated, I see

    W: plymouth: The plugin label.so is missing, the selected theme might not work as expected.
    W: plymouth: You might want to install the plymouth-themes and plymouth-label package to fix this.

The following plymouth packages are installed:

    # dpkg -l | grep plymouth
    ii libplymouth4:amd64 0.9.2-3ubuntu13 amd64 graphical boot animation and logger - shared libraries
    ii plymouth 0.9.2-3ubuntu13 amd64 boot animation, logger and I/O multiplexer
    ii plymouth-theme-ubuntu-text 0.9.2-3ubuntu13 amd64 boot animation, logger and I/O multiplexer - ubuntu text theme

A minimal install of Ubuntu should pull in the appropriate packages so that Plymouth doesn't complain. (As it is, I don't see much of a splash screen on startup.)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Launchpad Janitor (janitor)]

This bug was fixed in the package plymouth - 0.9.2-3ubuntu15

---------------
plymouth (0.9.2-3ubuntu15) yakkety; urgency=medium

  * Fix hook script to not print warnings about label.so when using the
    ubuntu-text theme. LP: #1578006.

 -- Steve Langasek <email address hidden> Wed, 04 May 2016 19:55:22 -0700

[Adam Conrad (adconrad)]

Hello Daniel, or anyone else affected,

Accepted plymouth into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/plymouth/0.9.2-3ubuntu13.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Daniel Richard G. (skunk)]

On a minimal install:

# update-initramfs -u
update-initramfs: Generating /boot/initrd.img-4.4.0-22-generic
W: plymouth: The plugin label.so is missing, the selected theme might not work as expected.
W: plymouth: You might want to install the plymouth-themes and plymouth-label package to fix this.

# apt-get install plymouth
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  plymouth-theme-ubuntu-text
Suggested packages:
  desktop-base plymouth-themes
The following packages will be upgraded:
  plymouth plymouth-theme-ubuntu-text
2 upgraded, 0 newly installed, 0 to remove and 19 not upgraded.
Need to get 116 kB of archives.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n]
Get:1 http://apt.example.com:3142/ubuntu xenial-proposed/main amd64 plymouth amd64 0.9.2-3ubuntu13.1 [107 kB]
Get:2 http://apt.example.com:3142/ubuntu xenial-proposed/main amd64 plymouth-theme-ubuntu-text amd64 0.9.2-3ubuntu13.1 [9,078 B]
Fetched 116 kB in 2s (39.0 kB/s)
(Reading database ... 82205 files and directories currently installed.)
Preparing to unpack .../plymouth_0.9.2-3ubuntu13.1_amd64.deb ...
Unpacking plymouth (0.9.2-3ubuntu13.1) over (0.9.2-3ubuntu13) ...
Preparing to unpack .../plymouth-theme-ubuntu-text_0.9.2-3ubuntu13.1_amd64.deb ...
Unpacking plymouth-theme-ubuntu-text (0.9.2-3ubuntu13.1) over (0.9.2-3ubuntu13) ...
Processing triggers for ureadahead (0.100.0-19) ...
Processing triggers for systemd (229-4ubuntu4) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up plymouth (0.9.2-3ubuntu13.1) ...
update-initramfs: deferring update (trigger activated)
update-rc.d: warning: start and stop actions are no longer supported; falling back to defaults
update-rc.d: warning: start and stop actions are no longer supported; falling back to defaults
Setting up plymouth-theme-ubuntu-text (0.9.2-3ubuntu13.1) ...
update-initramfs: deferring update (trigger activated)
Processing triggers for initramfs-tools (0.122ubuntu8) ...
update-initramfs: Generating /boot/initrd.img-4.4.0-22-generic

# update-initramfs -u
update-initramfs: Generating /boot/initrd.img-4.4.0-22-generic

Fix is verified.

(Did notice this unrelated issue, however: https://bugs.launchpad.net/bugs/1580445 )

[Launchpad Janitor (janitor)]

This bug was fixed in the package plymouth - 0.9.2-3ubuntu13.1

---------------
plymouth (0.9.2-3ubuntu13.1) xenial; urgency=medium

  * Fix hook script to not print warnings about label.so when using the
    ubuntu-text theme. LP: #1578006.

 -- Steve Langasek <email address hidden> Tue, 10 May 2016 10:28:16 -0700

[Adam Conrad (adconrad)]

The verification of the Stable Release Update for plymouth has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.