Hello

I tried looking at the overflow but i seriously have no idea what are
all these regions the gfx_region_update_* gets.

There is some scn_x and scn_y but these do not seem to be the screen
coordinates of the region.

If I could tell for what region I am doing the update (that is the
x,y,width,height of the region in screen coordinates) I could set the
viewport accordingly so that the content does not overflow.

At the very least the patch replicates the same breakage in much fewer
lines of code.

Thanks

Michal