force_extend_topology() was added before the resolve loop to de-clone a fresh IDD on
integrated-screen boxes (laptops), but its bare SDC_TOPOLOGY_EXTEND preset is
ACCESS_DENIED from the Session-0 service context on a HEADLESS box and broke the IDD
auto-activation there: resolve_gdi_name stayed None -> "not an active display path" ->
black screen. That regressed the headless/primary platform (live RTX box).
Revert to the proven c7ef0e4 flow: resolve FIRST (Windows auto-activates the IDD as its
own extended path), and force-EXTEND only as the FALLBACK when resolve returns None (the
integrated-screen clone case, observed live to leave resolve None). The success path is
byte-identical to c7ef0e4 (resolve -> set_active_mode -> isolate_displays_ccd).
Validated live: the headless RTX box streams again (probe: frames flow, driver attaches
to the ring, host/driver render LUIDs match).
Reviewed multi-agent + adversarial: no regression on the validated headless path or the
observed Optimus-laptop clone path (a cloned IddCx target resolves to None there, so the
is_none() fallback fires + de-clones). Known theoretical caveat, documented inline and
unobserved for IddCx but untested across GPU/driver/OS: a CCD clone that manifests as a
shared-source ACTIVE path would resolve to Some and bypass the is_none() gate. Follow-up:
widen the gate (a target_is_cloned helper) once an integrated-screen box is available to
validate.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
enricobuehler
a93f84cadf