[PATCH AUTOSEL 5.10 022/116] drm/amd/display: check top_pipe_to_program pointer

[Sasha Levin]

From: Yang Li <yang....@linux.alibaba.com>

[ Upstream commit a689e8d1f80012f90384ebac9dcfac4201f9f77e ]

Clang static analysis reports this error

drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc.c:2870:7: warning:
Dereference of null pointer [clang-analyzer-core.NullDereference]
                if
(top_pipe_to_program->stream_res.tg->funcs->lock_doublebuffer_enable) {
                    ^

top_pipe_to_program being NULL is caught as an error
But then it is used to report the error.

So add a check before using it.

Reported-by: Abaci Robot <ab...@linux.alibaba.com>
Signed-off-by: Yang Li <yang....@linux.alibaba.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/gpu/drm/amd/display/dc/core/dc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c 
b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 284ed1c8a35ac..93f5229c303e7 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -2436,7 +2436,8 @@ static void commit_planes_for_stream(struct dc *dc,
        }
 
        if ((update_type != UPDATE_TYPE_FAST) && 
stream->update_flags.bits.dsc_changed)
-               if 
(top_pipe_to_program->stream_res.tg->funcs->lock_doublebuffer_enable) {
+               if (top_pipe_to_program &&
+                       
top_pipe_to_program->stream_res.tg->funcs->lock_doublebuffer_enable) {
                        if (should_use_dmub_lock(stream->link)) {
                                union dmub_hw_lock_flags hw_locks = { 0 };
                                struct dmub_hw_lock_inst_flags inst_flags = { 0 
};
-- 
2.34.1