This is a note to let you know that I've just added the patch titled
drm/amd/display: Validate hw_points_num before using it
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-amd-display-validate-hw_points_num-before-using-.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b6ea496a3276a22dce5954fb120ba00e32648b8e
Author: Alex Hung <alex.hung@xxxxxxx>
Date: Mon Jul 10 18:23:58 2023 -0600
drm/amd/display: Validate hw_points_num before using it
[ Upstream commit 58c3b3341cea4f75dc8c003b89f8a6dd8ec55e50 ]
[WHAT]
hw_points_num is 0 before ogam LUT is programmed; however, function
"dwb3_program_ogam_pwl" assumes hw_points_num is always greater than 0,
i.e. substracting it by 1 as an array index.
[HOW]
Check hw_points_num is not equal to 0 before using it.
Reviewed-by: Harry Wentland <harry.wentland@xxxxxxx>
Signed-off-by: Alex Hung <alex.hung@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_dwb_cm.c b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_dwb_cm.c
index 6a3d3a0ec0a36..0f2e7fba0c938 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_dwb_cm.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_dwb_cm.c
@@ -243,6 +243,9 @@ static bool dwb3_program_ogam_lut(
return false;
}
+ if (params->hw_points_num == 0)
+ return false;
+
REG_SET(DWB_OGAM_CONTROL, 0, DWB_OGAM_MODE, 2);
current_mode = dwb3_get_ogam_current(dwbc30);
