[PATCH 2/2] drm/amd/display: Fix null check for pipe_ctx->plane_state in hwss_setup_dpp

[Zicheng Qu]

This commit addresses a null pointer dereference issue in
hwss_setup_dpp(). The issue could occur when pipe_ctx->plane_state is
null. The fix adds a check to ensure `pipe_ctx->plane_state` is not null
before accessing. This prevents a null pointer dereference.

Fixes: 0baae6246307 ("drm/amd/display: Refactor fast update to use new HWSS 
build sequence")
Signed-off-by: Zicheng Qu <quzich...@huawei.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c 
b/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
index 7ee2be8f82c4..bb766c2a7417 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
@@ -881,6 +881,9 @@ void hwss_setup_dpp(union block_sequence_params *params)
        struct dpp *dpp = pipe_ctx->plane_res.dpp;
        struct dc_plane_state *plane_state = pipe_ctx->plane_state;
 
+       if (!plane_state)
+               return;
+
        if (dpp && dpp->funcs->dpp_setup) {
                // program the input csc
                dpp->funcs->dpp_setup(dpp,
-- 
2.34.1