From 9f60fce433a6b455db203b7c22c01056bd2a1d27 Mon Sep 17 00:00:00 2001
From: Mikita Lipski <mikita.lipski@amd.com>
Date: Mon, 15 Nov 2021 16:07:38 -0500
Subject: drm/amd/display: prevent reading unitialized links
Git-commit: 0755c38eb007196a5f779298b4a5f46c4eec41d2
Patch-mainline: v5.16-rc5
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
[why/how]
The function can be called on boot or after suspend when
links are not initialized, to prevent it guard it with
NULL pointer check
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Pavle Kotarac <Pavle.Kotarac@amd.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/dc/dc_link.h | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h
index b01077a6af0e..fad3d883ed89 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -226,6 +226,8 @@ static inline void get_edp_links(const struct dc *dc,
*edp_num = 0;
for (i = 0; i < dc->link_count; i++) {
// report any eDP links, even unconnected DDI's
+ if (!dc->links[i])
+ continue;
if (dc->links[i]->connector_signal == SIGNAL_TYPE_EDP) {
edp_links[*edp_num] = dc->links[i];
if (++(*edp_num) == MAX_NUM_EDP)
--
2.38.1