drm/amd/display: fix dereferencing possible ERR_PTR()

This patch fixes static checker warning caused by
"36cc549d5986: "drm/amd/display: disable CRTCs with
NULL FB on their primary plane (V2)"

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Shirish S <shirish.s@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Alex Deucher <alexander.deucher@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 9e2f673..ae512ec 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -4854,6 +4854,9 @@ static int dm_atomic_check_plane_state_fb(struct drm_atomic_state *state,
                        return -EDEADLK;
 
                crtc_state = drm_atomic_get_crtc_state(plane_state->state, crtc);
+               if (IS_ERR(crtc_state))
+                       return PTR_ERR(crtc_state);
+
                if (crtc->primary == plane && crtc_state->active) {
                        if (!plane_state->fb)
                                return -EINVAL;