drm/amd/display: Fix amdgpu_dm bugs found by smatch

drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:2760
create_eml_sink() warn: variable dereferenced before check
'aconnector->base.edid_blob_ptr' (see line 2758)
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:4270
amdgpu_dm_atomic_commit_tail() warn: variable dereferenced before check
'dm_new_crtc_state->stream' (see line 4266)
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:4417
dm_restore_drm_connector_state() warn: variable dereferenced before
check 'disconnected_acrtc' (see line 4415)

Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Sun peng Li <Sunpeng.Li@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 8b0fb25d84a6ea2cb6548c0a755d5bdaad658ea9..5025dafb0517af219e5beb979642df63db025d09 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2709,7 +2709,7 @@ static void create_eml_sink(struct amdgpu_dm_connector *aconnector)
                        .link = aconnector->dc_link,
                        .sink_signal = SIGNAL_TYPE_VIRTUAL
        };
-       struct edid *edid = (struct edid *) aconnector->base.edid_blob_ptr->data;
+       struct edid *edid;
 
        if (!aconnector->base.edid_blob_ptr ||
                !aconnector->base.edid_blob_ptr->data) {
@@ -2721,6 +2721,8 @@ static void create_eml_sink(struct amdgpu_dm_connector *aconnector)
                return;
        }
 
+       edid = (struct edid *) aconnector->base.edid_blob_ptr->data;
+
        aconnector->edid = edid;
 
        aconnector->dc_em_sink = dc_link_add_remote_sink(
@@ -4198,13 +4200,13 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
                update_stream_scaling_settings(&dm_new_con_state->base.crtc->mode,
                                dm_new_con_state, (struct dc_stream_state *)dm_new_crtc_state->stream);
 
+               if (!dm_new_crtc_state->stream)
+                       continue;
+
                status = dc_stream_get_status(dm_new_crtc_state->stream);
                WARN_ON(!status);
                WARN_ON(!status->plane_count);
 
-               if (!dm_new_crtc_state->stream)
-                       continue;
-
                /*TODO How it works with MPO ?*/
                if (!dc_commit_planes_to_stream(
                                dm->dc,
@@ -4337,9 +4339,11 @@ void dm_restore_drm_connector_state(struct drm_device *dev,
                return;
 
        disconnected_acrtc = to_amdgpu_crtc(connector->encoder->crtc);
-       acrtc_state = to_dm_crtc_state(disconnected_acrtc->base.state);
+       if (!disconnected_acrtc)
+               return;
 
-       if (!disconnected_acrtc || !acrtc_state->stream)
+       acrtc_state = to_dm_crtc_state(disconnected_acrtc->base.state);
+       if (!acrtc_state->stream)
                return;
 
        /*