From 2a00299e7447395d0898e7c6214817c06a61a8e8 Mon Sep 17 00:00:00 2001
From: Leo Li <sunpeng.li@amd.com>
Date: Thu, 9 Feb 2023 12:15:21 -0500
Subject: [PATCH] drm/amd/display: Fail atomic_check early on normalize_zpos error
Git-commit: 2a00299e7447395d0898e7c6214817c06a61a8e8
Patch-mainline: v6.2
References: git-fixes
Alt-commit: ac0bb08d2cb711dc0e332f91c4e67783fcbe3439

[Why]

drm_atomic_normalize_zpos() can return an error code when there's
modeset lock contention. This was being ignored.

[How]

Bail out of atomic check if normalize_zpos() returns an error.

Fixes: b261509952bc ("drm/amd/display: Fix double cursor on non-video RGB MPO")
Signed-off-by: Leo Li <sunpeng.li@amd.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 93dee3d1a483..9c7b69d377bd 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -9658,7 +9658,11 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 	 * `dcn10_can_pipe_disable_cursor`). By now, all modified planes are in
 	 * atomic state, so call drm helper to normalize zpos.
 	 */
-	drm_atomic_normalize_zpos(dev, state);
+	ret = drm_atomic_normalize_zpos(dev, state);
+	if (ret) {
+		drm_dbg(dev, "drm_atomic_normalize_zpos() failed\n");
+		goto fail;
+	}
 
 	/* Remove exiting planes if they are modified */
 	for_each_oldnew_plane_in_state_reverse(state, plane, old_plane_state, new_plane_state, i) {
-- 
2.35.3