Comment 10 for bug 108056

For anyone still having issues on 855 hardware, specifically when switching VTs, suspending, shutting down, (or even starting the X server up), and wanting to help debug this issue further, I'm put online a .deb (and sources etc..):
http://www2.eng.cam.ac.uk/~pcjc2/ubuntu/debug/
http://www2.eng.cam.ac.uk/~pcjc2/ubuntu/debug/xserver-xorg-video-intel_2.1.1-0ubuntu9~pcjc2.tst_i386.deb

This has the latest ubuntu version of the driver, with all known fixes that have been pushed to Ubuntu. It has an experimental patch of mine to avoid blinking the blackight like crazy when starting the server up, which also has possible side-effects for the load/restore path.

The useful bit, is a load of extra log output at nearly every stage of the restore path. If its failing there, we should be able to narrow down where.

I've added calls to sync() after every log messge I added, so _hopefully_ some of this will make it to disk if the machine hard-locks, although hardware write-caching on the disk may put pay to that.

You might try disabling that before VT switching with:
hdparm -W 0 /dev/HARD_DRIVE

Those who know how to attach strace from a remote machine will be able to see everything even if the machine locks.

I'd be interested to see log output from this for anyone who still has failures. (Running this test version of the driver).