[SRU] Display broken in initramfs on ARM64 laptops

[Tobias Heider]

[ Impact ]

On affected hardware, the display only works after the initramfs.
This means there is no visible input field if disk encryption was selected in the installer.
The same of course applies for any other output during the initramfs.

[ Test Plan ]

To reproduce the issue, install an affected machine with disk encryption or add break= to the kernel command line to get an interactive initramfs shell.
With the bug present the screen stays dark. It might still be possible to enter
the passphrase blindly or exit the debug shell. After modules are loaded from the root file system the screen should start working.

With the patch applied there should be visible output for the password or shell prompt in the initramfs.

[ Where problems could occur ]

The fix should only include additional modules, we should make sure not to accidentally drop any functionality in the process.

[ Other Info ]

Since dracut and initramfs-tools behave similar enough the same test plan should apply to both. Both are already fixed in questing and there is positive test feedback from users in discourse https://discourse.ubuntu.com/t/faq-ubuntu-25-04-on-snapdragon-x-elite/61016/18

[Tobias Heider (tobhe)]

We could either fix this in ubuntu-x1e-settings and include the required panel manually or make initramfs-tools detect panels automatically and include them. The second option probably scales better.

[Benjamin Drung (bdrung)]

Better fix initramfs-tools. How is the panel module named?

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/2107477

[Tobias Heider (tobhe)]

bdrung: that would be panel_samsung_atna33xc20. Do you think we could solve this in a way where any panel module that is currently loaded would be included?

[Benjamin Drung (bdrung)]

We had a debug session. The result:

* MODULES=most needs to include =drivers/gpu/drm/panel
* MODULES=dep needs to look for panel_* modules
* dracut needs to include =drivers/gpu/drm/panel in the simpledrm module (similar to the drm module)

[Benjamin Drung (bdrung)]

dracut fix: https://github.com/dracut-ng/dracut-ng/pull/1312

[Launchpad Janitor (janitor)]

This bug was fixed in the package dracut - 107-1ubuntu1

---------------
dracut (107-1ubuntu1) questing; urgency=medium

  * Merge with Debian unstable (LP: #2111570). Remaining changes:
    - drop udevsettle patch (these kind of patches should be applied upstream)
    - dracut-core:
      - demote cryptsetup, systemd-cryptsetup, dmsetup, kpartx, lvm2,
        and mdadm to suggests
      - demote binutils to suggests. its only needed when using UEFI executables
    - Include all packages with dracut modules in Apport bug reports
    - autopkgtest: enable tests for s390x again
    - autopkgtest: add TEST-70-ISCSI and TEST-71-ISCSI-MULTI
    - Plymouth hook: Use alternatives instead of plymouth-set-default-theme
    - run upstream-dracut-live autopkgtest on armhf and ppc64el
    - Add update-initramfs (derived from initramfs-tools)
    - Drop debian-initramfs-post-update.patch. Let update-initramfs call the
      bootloader hooks instead of dracut itself.
    - Add bash completion for update-initramfs
    - Avoid updating the initramfs twice for some cases
    - plymouth: Only pull in the SimpleDRM driver by default
  * autopkgtest: depend on curl for test 60-NFS
  * fix(simpledrm): add =drivers/gpu/drm/panel (LP: #2107477)

dracut (107-1) unstable; urgency=medium

  [ Thomas Lange ]
  * new upstream 107
  * drop 90overlay-root in favor of the overlayfs, Closes: #1017039
  * refresh patches, drop patches included upstream
  * rename module systemd-sysusers
  * add module 45simpledrm
  * update revdate for man pages

  [ Benjamin Drung ]
  * Stop shipping the dmraid module (Closes: #1099698)
  * Set -H --hostonly-mode=sloppy as default arguments via a config file
  * d/copyright: fix lintian's old-fsf-address-in-copyright-file
  * autopkgtest:
    - enable test 12 but skip using kernel-install due to bug #1104848
    - Remove possible masked systemd-udevd to avoid test 10 to fail

dracut (106-6) unstable; urgency=medium

  [ cacin ]
  * Drop nonexistent Recommends: dmraid (Closes: #1099698)

dracut (106-5) unstable; urgency=medium

  * disable upstream test 43

dracut (106-4) unstable; urgency=medium

  * skip upstream test 12, time out on Debian

dracut (106-3) unstable; urgency=medium

  * disable autopkgtest for s390x, Closes: #1096001
  * debian/rules: remove dracut.html which does not exist

 -- Benjamin Drung <email address hidden> Fri, 23 May 2025 14:54:03 +0200

[Benjamin Drung (bdrung)]

https://salsa.debian.org/kernel-team/initramfs-tools/-/merge_requests/170 got merged and released in initramfs-tools 0.149. Thus it is fixed in initramfs-tools 0.149ubuntu1 in questing.

[Tobias Heider (tobhe)]

initramfs-tools MR for plucky at https://code.launchpad.net/~tobhe/ubuntu/+source/initramfs-tools/+git/initramfs-tools/+merge/487758

[Timo Aaltonen (tjaalton)]

Hello Tobias, or anyone else affected,

Accepted initramfs-tools into plucky-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/initramfs-tools/0.147ubuntu1.1 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 on 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, what testing has been performed on the package and change the tag from verification-needed-plucky to verification-done-plucky. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-plucky. In either case, without details of your testing we will not be able to proceed.

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

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Ubuntu SRU Bot (ubuntu-sru-bot)]

All autopkgtests for the newly accepted initramfs-tools (0.147ubuntu1.1) for plucky have finished running.
The following regressions have been reported in tests triggered by the package:

clevis/20-1 (ppc64el)
cryptsetup/2:2.7.5-1ubuntu2 (arm64)
initramfs-tools/unknown (i386)
kdump-tools/1:1.10.5ubuntu2 (amd64, ppc64el)
multipath-tools/0.9.9-1ubuntu4 (amd64)

Please visit the excuses page listed below and investigate the failures, proceeding afterwards as per the StableReleaseUpdates policy regarding autopkgtest regressions [1].

https://people.canonical.com/~ubuntu-archive/proposed-migration/plucky/update_excuses.html#initramfs-tools

[1] https://wiki.ubuntu.com/StableReleaseUpdates#Autopkgtest_Regressions

Thank you!

[Johan (cjpalm)]

I have tested this on a Lenovo Yoga slim 7x Arm64 with Ubuntu 25.04 Plucky and can confirm that the bug now is fixed.

[Tobias Heider (tobhe)]

Also confirmed working on my test machine. The reported autopkgtest regressions look like infrastructure issues, triggering a rerun and updating the test tags.

EDIT: seems the tests all passed on second try.