[Intel-gfx] [PATCH 07/15] drm/i915: Unconditionally clear plane_state->visible flag

[Maarten Lankhorst]

If we ever hit bugs in our readout code we may have set
plane_state->visible without setting a fb/crtc. Our code implicitly
assumes that plane_state->visible is only true when both are set,
so we will either null deref in intel_fbc_choose_crtc() or
do something bad during the actual commit which cares even more.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_atomic_plane.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_atomic_plane.c b/drivers/gpu/drm/i915/intel_atomic_plane.c
index e067fb531a29..d754a8ba9ffb 100644
--- a/drivers/gpu/drm/i915/intel_atomic_plane.c
+++ b/drivers/gpu/drm/i915/intel_atomic_plane.c
@@ -117,10 +117,10 @@ int intel_plane_atomic_check_with_state(const struct intel_crtc_state *old_crtc_
 	struct intel_plane *intel_plane = to_intel_plane(plane);
 	int ret;
 
+	intel_state->base.visible = false;
 	if (!intel_state->base.crtc && !old_plane_state->base.crtc)
 		return 0;
 
-	intel_state->base.visible = false;
 	ret = intel_plane->check_plane(crtc_state, intel_state);
 	if (ret)
 		return ret;
@@ -152,6 +152,7 @@ static int intel_plane_atomic_check(struct drm_plane *plane,
 	const struct drm_crtc_state *old_crtc_state;
 	struct drm_crtc_state *new_crtc_state;
 
+	new_plane_state->visible = false;
 	if (!crtc)
 		return 0;
 
-- 
2.18.0