From: Wenjing Liu <wenjing.liu@amd.com>
Date: Tue, 20 Jan 2026 22:40:07 +0000 (+0000)
Subject: drm/amd/display: Fix a NULL pointer dereference in dcn20_hwseq.c
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9d6bd60695806782bec8562ab73aefafce067f05;p=thirdparty%2Flinux.git

drm/amd/display: Fix a NULL pointer dereference in dcn20_hwseq.c

[why]
hws->funcs.dccg_init is accessed without checking if it is NULL, which
may lead to a NULL pointer dereference.

[how]
Add a NULL check before calling dccg_init.

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
index 87a1dc27def4..307e8f8060e6 100644
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
@@ -3140,7 +3140,8 @@ void dcn20_fpga_init_hw(struct dc *dc)
 
 	dcn10_hubbub_global_timer_enable(dc->res_pool->hubbub, true, 2);
 
-	hws->funcs.dccg_init(hws);
+	if (hws->funcs.dccg_init)
+		hws->funcs.dccg_init(hws);
 
 	if (dc->res_pool->dccg && dc->res_pool->dccg->funcs && dc->res_pool->dccg->funcs->refclk_setup)
 		dc->res_pool->dccg->funcs->refclk_setup(dc->res_pool->dccg);