Ravi Sharma from the Ubuntu Foundations Team summarized the work done over the past year to ensure full support for the ARM64 architecture in Ubuntu. It was noted that improvements in tooling and infrastructure, as well as the promotion of changes to the core of the Linux kernel, have led to resolving specific ARM64 issues over the year, such as the distribution of packages through a separate repository, the lack of support for live patches for the kernel, limited capabilities for gamers, and the unavailability of Secure Boot on laptops with Qualcomm Snapdragon chips.
Key Achievements:
- Packages for the ARM64 architecture have been moved from the ports (ports.ubuntu.com) to the main Ubuntu archive (archive.ubuntu.com), allowing them to utilize the same infrastructure as used for the x86_64 architecture. ARM64 packages are now delivered through the primary mirror system, improving speed and reliability during download. The migration required changes to the cloud-init, live-build, livecd-rootfs, and ubuntu-release-upgrader packages. These changes are included in Ubuntu 26.04 and are being backported for Ubuntu 24.04 LTS.
- The Livepatch service, which allows for kernel fixes on a running system without rebooting, has been extended to ARM64-based systems. Previously, Live patches were available only for the x86_64 architecture as the ARM64 Linux kernel lacked support for reliable stack traces (CONFIG_HAVE_RELIABLE_STACKTRACE) for detecting activity related to interrupt handling, and the objtool and kpatch tooling lacked complete capabilities for assessing the state before and after applying the patch. Support for Live patches for ARM64 is provided in Ubuntu 26.04 LTS and Ubuntu Core 26.
- A stable snap package with the Steam client has been created for the ARM64 architecture. Since the Steam client for Linux is only available for the x86 architecture, an emulation layer based on the FEX package is used to run it on ARM64 systems. The emulation supports GPU pass-through and uses Wine, Proton, DXVK, and vkd3d to run computer games compiled for the x86_64 architecture and distributed through the Steam catalog. The snap package's operation has been tested on laptops with Qualcomm Snapdragon X Elite chips, NVIDIA DGX Spark, and Radxa Orion O6.
- Support has been added for laptops based on Qualcomm Snapdragon X Elite chips, such as the Lenovo Thinkpad X13s/T14s and Dell XPS 9345. Initially, support for these devices was included in the base ISO image for ARM64 systems, but it could not be used for booting in Secure Boot mode due to the use of separate Device Tree configurations, which the laptop firmware did not pass to the Linux kernel. The necessary Device Tree settings were loaded by the GRUB loader from a separate file that wasn't covered by the digital signature.
To resolve the issue, the kernel and the Device Tree database were merged into a single monolithic EFI file, similar to UKI (Unified Kernel Image), signed with the distribution's digital signature. A new EFI layer called 'stubble' was created for loading this file, determining the device model through SMBIOS during boot, selecting the appropriate Device Tree data, and injecting it into the kernel without breaking the Secure Boot trust chain. Work is underway to implement support for laptops with Snapdragon X2 Elite chips.
- A prototype bootable image based on Ubuntu 26.04 has been prepared for laptops with ARM64 SoC CIX P1, which, unlike Snapdragon, allows configuration to be determined through ACPI tables without the use of Device Tree.
- Google has announced the release of official Chrome builds for Linux systems based on ARM64 architecture, allowing the Chrome browser with the Widevine Content Decryption Module (CDM), which is not available in Chromium, to run on ARM64 builds of Ubuntu. The supply of Widevine will enable viewing copyright-protected media content (DRM) hosted on services like Netflix, Spotify, and Disney+ without third-party patches. Support for Widevine is also planned to be integrated into snap packages with Firefox and Spotify.
- New application builds are available in snap format for ARM64 architecture. Among other things, the publication of snap packages for OnlyOffice, FreeCAD, and Teams for Linux has begun for ARM64.
Source: opennet.ru
