From a9d951b007904942e2519bc8ff7ba2d1b4121060 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Thu, 7 Dec 2023 21:34:34 +0200 Subject: [PATCH] drm/i915: Fix intel_atomic_setup_scalers() plane_state handling MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit commit c3070f080f9ba18dea92eaa21730f7ab85b5c8f4 upstream. Since the plane_state variable is declared outside the scaler_users loop in intel_atomic_setup_scalers(), and it's never reset back to NULL inside the loop we may end up calling intel_atomic_setup_scaler() with a non-NULL plane state for the pipe scaling case. That is bad because intel_atomic_setup_scaler() determines whether we are doing plane scaling or pipe scaling based on plane_state!=NULL. The end result is that we may miscalculate the scaler mode for pipe scaling. The hardware becomes somewhat upset if we end up in this situation when scanning out a planar format on a SDR plane. We end up programming the pipe scaler into planar mode as well, and the result is a screenfull of garbage. Fix the situation by making sure we pass the correct plane_state==NULL when calculating the scaler mode for pipe scaling. Cc: stable@vger.kernel.org Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20231207193441.20206-2-ville.syrjala@linux.intel.com Reviewed-by: Jani Nikula (cherry picked from commit e81144106e21271c619f0c722a09e27ccb8c043d) Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/display/skl_scaler.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/skl_scaler.c b/drivers/gpu/drm/i915/display/skl_scaler.c index 1e7c972..8a934ba 100644 --- a/drivers/gpu/drm/i915/display/skl_scaler.c +++ b/drivers/gpu/drm/i915/display/skl_scaler.c @@ -504,7 +504,6 @@ int intel_atomic_setup_scalers(struct drm_i915_private *dev_priv, { struct drm_plane *plane = NULL; struct intel_plane *intel_plane; - struct intel_plane_state *plane_state = NULL; struct intel_crtc_scaler_state *scaler_state = &crtc_state->scaler_state; struct drm_atomic_state *drm_state = crtc_state->uapi.state; @@ -536,6 +535,7 @@ int intel_atomic_setup_scalers(struct drm_i915_private *dev_priv, /* walkthrough scaler_users bits and start assigning scalers */ for (i = 0; i < sizeof(scaler_state->scaler_users) * 8; i++) { + struct intel_plane_state *plane_state = NULL; int *scaler_id; const char *name; int idx, ret; -- 2.7.4