Fix Fedora 41 RPM dependency issue with liblttng-ust compatibility handling

[Copilot]

The GitHub Actions runner binaries are compiled with a dependency on liblttng-ust.so.0, but Fedora 41 ships with lttng-ust version 2.13.8 which provides liblttng-ust.so.1. This causes RPM installation failures with errors like:

Problem: conflicting requests
  - nothing provides liblttng-ust.so.0()(64bit) needed by github-actions-agent-2.325.0-3.fc41.x86_64

The root cause was that the installdependencies.sh script for Fedora-based systems only attempted to install the lttng-ust package without any fallback handling for version compatibility, unlike Debian-based systems which have robust fallback logic.

Changes Made

1. Enhanced Fedora dependency installation logic: Modified the dnf installation section in src/Misc/layoutbin/installdependencies.sh to:

   • Install basic dependencies first (openssl-libs, krb5-libs, zlib, libicu)
   • Use a new dnf_with_lttng_fallbacks() function for lttng-ust handling
   • Check if the installed package provides the required liblttng-ust.so.0
   • Create compatibility symlinks when needed (e.g., liblttng-ust.so.0 → liblttng-ust.so.1)
   • Update ldconfig to register the new symlinks

2. Updated documentation: Enhanced docs/start/envlinux.md to document the automatic compatibility handling for Fedora-based systems.

Testing

• Verified that existing Debian/Ubuntu systems continue to work correctly
• Created unit tests to validate the Fedora fallback logic
• Confirmed the build process works without issues after changes

This approach provides a robust solution that maintains backward compatibility while supporting newer Fedora versions that ship with updated lttng-ust libraries.

Fixes #3937.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• esm.ubuntu.com
  • Triggering command: /usr/lib/apt/methods/https (dns block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/CompositeLimit
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.413/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 34283 --endpoint 127.0.0.1:034283 --role client --parentprocessid 4771 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/RepositoryActionWithInvalidWrapperActionfile_Node
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.413/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 34283 --endpoint 127.0.0.1:034283 --role client --parentprocessid 4771 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/RepositoryActionWithWrapperActionfile_Node
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.413/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 34283 --endpoint 127.0.0.1:034283 --role client --parentprocessid 4771 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/repositoryactionwithactionfileanddockerfile
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.413/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 34283 --endpoint 127.0.0.1:034283 --role client --parentprocessid 4771 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/repositoryactionwithdockerfile
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.413/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 34283 --endpoint 127.0.0.1:034283 --role client --parentprocessid 4771 --telemetryoptedin false (http block)
• https://api.github.com/repos/actions/download-artifact/tarball/master
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.413/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 34283 --endpoint 127.0.0.1:034283 --role client --parentprocessid 4771 --telemetryoptedin false (http block)
• https://api.github.com/repos/actions/setup-node/tarball/v1
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.413/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 34283 --endpoint 127.0.0.1:034283 --role client --parentprocessid 4771 --telemetryoptedin false (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

---

💬 Share your feedback on Copilot coding agent for the chance to win a $200 gift card! Click here to start the survey.