FAILED: patch "[PATCH] Revert "drm/amd/display: fix dereferencing possible" failed to apply to 4.17-stable tree

The patch below does not apply to the 4.17-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: Harry Wentland <[email protected]>
Date: Thu, 12 Apr 2018 10:51:51 -0400
Subject: [PATCH] Revert "drm/amd/display: fix dereferencing possible
ERR_PTR()"
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This reverts commit cd2d6c92a8e39d7e50a5af9fcc67d07e6a89e91d.

index 265f0166f688..0c29f3b97398 100644
@@ -4941,9 +4941,6 @@ static int dm_atomic_check_plane_state_fb(struct drm_atomic_state *state,
 			return -EDEADLK;
 
 		crtc_state = drm_atomic_get_crtc_state(plane_state->state, crtc);
-		if (IS_ERR(crtc_state))
-			return PTR_ERR(crtc_state);
-
 		if (crtc->primary == plane && crtc_state->active) {
 			if (!plane_state->fb)
 				return -EINVAL;