[ltp] Possibly Solved: i855-based ThinkPad R51 suspend-to-RAM

[Ingo van Lil]

On 14 Apr 2005, Ingo van Lil wrote:

> I have to correct myself: The vbetool stuff doesn't seem to be required
> at all. Merely saving and restoring the contents of
> /proc/bus/pci/00/02.0 seems to do the trick. I still have to switch to a
> text console to prevent the X server from dying, though.

Dammit! It used to work just perfectly for three days in a row (no
reboot), but yesterday it suddenly started making problems: At resume
there were some cryptic "mtrr" messages and the desktop suddenly looked
broken. Windows were only partially visible (only some frame fragments
most of the time), in some places text was missing, hard to describe.
Restarting the X server didn't help, using a different X graphics driver
(vesa) did. So, assumedly some kernel driver crashed and prevented the
accellerated driver from working correctly.
Unfortunately the effect wasn't just a bizarre one-time symptom, it now
happens reproducably after every suspend and can only be fixed by
rebooting (which renders suspend-to-ram perfectly useless). I worked
around it by removing the intel-agp/i915 stuff from the kernel and thus
disabling DRM. I'd still like to know what made it stop working so
suddenly.

        Cheers,
            Ingo