Identifying if the issue is a bug or not
If you aren't sure if you have encountered a software bug in Ubuntu, then you would want to seek help in determining if the issue is a bug or not from here.
If you have confirmed the issue is a bug, please read on.
Determining which type of bug you have
Not all bugs where X seems to be the root cause are in fact an X related bug. Hence, here is documentation on potential root causes:
i855 is Unsupported - Explanation of why i845, i855, i865, etc. chips aren't supported
Glossary - Common error messages and terminology
X Transitions - Explanation for "installing xserver-xorg-core would break existing software"
Reporting a confirmed X bug to Launchpad
Initial filing of the report
First, please install the package xdiagnose.
Next, ensure you click the Yes button for attaching additional debugging information after running the following via a terminal:
Include developer information in your report
One will want to answer the following questions in order for a developer to address the issue:
- Does the report include debugging information from the relevant article relating to the reported issue?
- Is this a regression?
- Does this happen in the latest version of Ubuntu?
- Does this happen in the latest version available from upstream?
Non-Graphical Booting - Running X manually, without a display manager (like lightdm, kdm, gdm...)
Wireless Without X - How to get a wireless network connection without X.
Direct Wired Without WAP - How to connect two laptops with direct ethernet cord.
Crashes and Freezes
X Backtracing - How to collect a backtrace for an X crash
Interpreting GPU Dumps - Ringbuffers, batchbuffers, and the meaning of intel_gpu_dump output
Valgrind - Debugging memory leaks
X Bisecting - Using bisection techniques to solve regressions or backport fixes
X/Testing/Touch - Touchscreen and multi-touch testing
Triaging and tagging X bugs
Please see here for more on triaging X bugs, and here for tagging.
Fixing an X crash
Video Resources at help.ubuntu.com