Here’s i915_error_state as requested on https://wiki.ubuntu.com/X/Troubleshooting/Freeze#. I made a copy (using cp), and I should mention that my first try to do so resulted in an error message: ”failed to extend” … and something about not having enough memory, in Finnish. When I preceded the command with LC_ALL=C to get the entire error message in English, the copying was suddenly successful. I hope this doesn’t mean the actual error state from the hang had been replaced by a new state which I’m now submitting.