Comment 23 for bug 1049630

(In reply to comment #18)
> I have not yet applied Alex's patch, [...]

Have you been able to test it in the meantime? It doesn't seem very likely it'll help, but...

> However, setting the vramlimit to 64 seems (2 reboots later) to clear up the
> corruption.
> vramlimit of 128, 256, and 0 (0 is ignored) each result in corruption

Can others affected by the problem confirm this?

Can you attach the dmesg output from with and without the working vramlimit?

(In reply to comment #19)
> When switching from tuxracer back to the native desktop mode 1366x768, the
> pointer was corrupted.
[...]
> Happily the first time a popup happened that covered the cursor for a moment
> it was restored.

Sounds like that was just intermittent corruption of the hardware cursor memory buffer then, e.g. due to a 3D driver bug causing it to be accidentally overridden. Probably not the same problem this report is about.

> BTW, I am a C programmer... If I knew where to start, I'd love to work on this
> problem from a code angle. I've looked at the code somewhat, but even in the
> code specific to my driver there is a lot of code in different places.

See e.g. rs690_mc_init() in drivers/gpu/drm/radeon/rs690.c .