drmkms on sandy bridge

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

After a recent -current update, using new drmkms on a sandy bridge,
I found that e.g., when using firefox, the cpu would hit 100%, all
would freeze, and I would have to hard reset, so no actual clue on
the problem.

This is on a:

i915drmkms0 at pci0 dev 2 function 0: Intel Sandy Bridge Integrated Graphics 
Device (rev. 0x09)


The work around was to pop

Option      "AccelMethod" "SNA"

in /etc/X11/xorg.conf, and things are now stable...


Cheers,

Patrick