https://bugs.freedesktop.org/show_bug.cgi?id=87568
--- Comment #3 from almos aaalmosss@gmail.com --- (In reply to Ian Romanick from comment #1)
It can be impossible to tell the difference between a draw that will take a very long time and a draw that will never complete, so possibly not. See also http://en.wikipedia.org/wiki/Halting_problem.
That's why WebGL was a bad idea in the first place.
As far as I can remember the timeout was 1 second, but since then I upgraded my system, kernel included, and when I tried now the timeout was 10s.