** Description changed: [ Impact ] Ubuntu Studio uses the lowlatency kernel. With 6.14, the lowlatency kernel is just the generic kernel with some bootargs to make it lowlatency. This breaks the Ubuntu Studio livefs and CD image builds. https://launchpad.net/~ubuntu-cdimage/+livefs/ubuntu/noble/ubuntustudio Problem 1) The postinst hook of the lowlatency-kernel package calls update-grub unconditionally which fails if the package is installed in a chroot. From a livefs build log: Processing triggers for dbus (1.14.10-4ubuntu4.1) ... Processing triggers for libgtk-3-0t64:amd64 (3.24.41-4ubuntu1.3) ... Processing triggers for shared-mime-info (2.4-4) ... Processing triggers for libgtk2.0-0t64:amd64 (2.24.33-4ubuntu1.1) ... Processing triggers for desktop-file-utils (0.27-2build1) ... Processing triggers for initramfs-tools (0.142ubuntu25.5) ... Processing triggers for hicolor-icon-theme (0.17-2) ... Processing triggers for libc-bin (2.39-0ubuntu8.5) ... Processing triggers for man-db (2.12.0-4build2) ... Processing triggers for dictionaries-common (1.29.7) ... Processing triggers for linux-image-6.14.0-24-generic (6.14.0-24.24~24.04.3) ... /etc/kernel/postinst.d/initramfs-tools: update-initramfs: Generating /boot/initrd.img-6.14.0-24-generic cryptsetup: ERROR: Couldn't resolve device overlay cryptsetup: WARNING: Couldn't determine root device cryptsetup: ERROR: Couldn't resolve device /dev/vdb Errors were encountered while processing: lowlatency-kernel Problem 2) The kernel flavor name changed from 'lowlatency' to 'generic'. This breaks livecd-rootfs. [2025-07-30 21:10:37] No catalog entry template for standard.live [2025-07-30 21:10:38] P: Begin unmounting filesystems... [2025-07-30 21:10:38] P: Saving caches... [2025-07-30 21:10:38] No kernel output for lowlatency! [2025-07-30 21:10:38] P: Begin unmounting filesystems... [2025-07-30 21:10:38] P: Saving caches... [2025-07-30 21:10:38] Build failed Problem 3) + The ISO kernel is the generic kernel now so needs additional boot args + to make it lowlatency. Otherwise 'Try Ubuntu Studio' will run the + generic kernel which is likely not what we want. + [ Test Plan ] 1. Trigger an Ubuntu Studio livefs build and watch it succeed. 2. Boot a resulting CD image and verify the running kernel is lowlatency. 3. Install Ubuntu Studio and verify the running kernel is lowlatency. [ Where Problems Could Occur ] Other consumers of livecd-rootfs could fail, i.e., other livefs builds might fail due to livecd-rootfs changes. Machines that have the lowlatency-kernel package installed might not update grub.cfg and hence not switch the kernel to lowlatency but continue to run with generic settings.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2119012 Title: Ubuntu Studio CD image build failure To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/livecd-rootfs/+bug/2119012/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
