Comment 12 for bug 305979

The following kernel commit may fix things.

Also, please include dmesg with bug reports.

commit 52440211dcdc52c0b757f8b34d122e11b12cdd50
Author: Keith Packard <email address hidden>
Date: Tue Nov 18 09:30:25 2008 -0800

    drm: move drm vblank initialization/cleanup to driver load/unload

    drm vblank initialization keeps track of the changes in driver-supplied
    frame counts across vt switch and mode setting, but only if you let it by
    not tearing down the drm vblank structure.

    Signed-off-by: Keith Packard <email address hidden>
    Signed-off-by: Dave Airlie <email address hidden>