FAILED: patch "[PATCH] drm/i915: Nuke skl_update_plane debug message from the pipe" failed to apply to 4.9-stable tree

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From: Maarten Lankhorst <[email protected]>
Date: Wed, 8 Mar 2017 13:00:07 +0100
Subject: [PATCH] drm/i915: Nuke skl_update_plane debug message from the pipe
update critical section
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printks are slow so we should not be doing them from the vblank evade critical section. These could explain why we sometimes seem to blow past our 100 usec deadline.

The problem has been there ever since commit c331879ce8ea ("drm/i915:
skylake sprite plane scaling using shared scalers.") but it may not have been readily visible until commit e1edbd44e23b ("drm/i915: Complain if we take too long under vblank evasion.") increased our chances of noticing it.

index 9ef54688872a..9481ca9a3ae7 100644
@@ -254,9 +254,6 @@ skl_update_plane(struct drm_plane *drm_plane,
 		int scaler_id = plane_state->scaler_id;
 		const struct intel_scaler *scaler;
 
-		DRM_DEBUG_KMS("plane = %d PS_PLANE_SEL(plane) = 0x%x\n",
-			      plane_id, PS_PLANE_SEL(plane_id));
-
 		scaler = &crtc_state->scaler_state.scalers[scaler_id];
 
 		I915_WRITE(SKL_PS_CTRL(pipe, scaler_id),