https://bugzilla.kernel.org/show_bug.cgi?id=43751
--- Comment #16 from Peter Barth kernel@won2.de 2013-04-24 21:06:27 --- I'll give mesa git a try and hope to be able to switch back to kwin soon. However, shouldn't the memory be freed after killing kwin and after shutting down xdm and so on? But that's not the case, the error resides.