In commit e3de42b68478a8c95dd27520e9adead2af9477a5 Author: Imre Deak <imre.deak@xxxxxxxxx> Date: Fri May 3 19:44:07 2013 +0200 drm/i915: force full modeset if the connector is in DPMS OFF mode a new function was added that walked over the set of connectors to see if any of the currently associated CRTC was switched off. This function walked an array of connectors, rather than the array of pointers to connectors contained in the drm_mode_set - i.e. it was dereferencing far past the end of the first connector. This only becomes an issue if we attempt to use a clone mode (i.e. more than one connector per CRTC) such that set->num_connectors > 1. Reported-by: Timo Aaltonen <tjaalton@xxxxxxxxxx> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65927 Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Imre Deak <imre.deak@xxxxxxxxx> Cc: Egbert Eich <eich@xxxxxxx> Cc: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/gpu/drm/i915/intel_display.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 9a10e71..6790600 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -8658,15 +8658,20 @@ static void intel_set_config_restore_state(struct drm_device *dev, } static bool -is_crtc_connector_off(struct drm_crtc *crtc, struct drm_connector *connectors, - int num_connectors) +is_crtc_connector_off(struct drm_mode_set *set) { int i; - for (i = 0; i < num_connectors; i++) - if (connectors[i].encoder && - connectors[i].encoder->crtc == crtc && - connectors[i].dpms != DRM_MODE_DPMS_ON) + if (set->num_connectors == 0) + return false; + + if (WARN_ON(set->connectors == NULL)) + return false; + + for (i = 0; i < set->num_connectors; i++) + if (set->connectors[i]->encoder && + set->connectors[i]->encoder->crtc == set->crtc && + set->connectors[i]->dpms != DRM_MODE_DPMS_ON) return true; return false; @@ -8679,10 +8684,8 @@ intel_set_config_compute_mode_changes(struct drm_mode_set *set, /* We should be able to check here if the fb has the same properties * and then just flip_or_move it */ - if (set->connectors != NULL && - is_crtc_connector_off(set->crtc, *set->connectors, - set->num_connectors)) { - config->mode_changed = true; + if (is_crtc_connector_off(set)) { + config->mode_changed = true; } else if (set->crtc->fb != set->fb) { /* If we have no fb then treat it as a full mode set */ if (set->crtc->fb == NULL) { -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html