If it says that direct rendering is enabled, then simply install libgl1-mesa-dri: glxinfo should then say that direct rendering is enabled. This seed problem should have been fixed after Flight 1
If Xorg.0.log says that it is disabled, then I guess it is a driver problem and you should confirm this bug.
Please report the output of
grep -i rendering /var/log/Xorg.0.log
If it says that direct rendering is enabled, then simply install libgl1-mesa-dri: glxinfo should then say that direct rendering is enabled. This seed problem should have been fixed after Flight 1
If Xorg.0.log says that it is disabled, then I guess it is a driver problem and you should confirm this bug.