Comment 25 for bug 1665802

Dropped priority.

Now we understand this problem, it's just going to be a series of workarounds in Mir, and Chris suggested another good one in the hangout today that might also fix it for radeon and nouveau (bug 1211700). Plus we have some workarounds proven already in comment #20.

Long term we need a proper fix in the driver, so it's a Mesa bug. A solution in theory already exists:
   https://www.usenix.org/legacy/event/atc11/tech/final_files/Kato.pdf