# Cross-reference — absorbed events vs Phase W wedge ground truth Baseline diff: Phase W cold canary `canary-wedge.head250k.jsonl` (56 MB, head-truncated to ~250k canary tid=6 events) vs ours `ours-postfix.jsonl` (28 MB). Default tid-map `6=1,4=11,7=2,12=7,14=9,15=10`. ## Total absorbed events: 8 | absorber | side | events | |---|---|---| | shared-global | ours | 1 | | wait-begin | canary | 1 | | nested-cs | canary | 6 (1 [E,L] pair = 6 events) | ## Per-absorbed-event analysis ### Nested-cs (6 events, canary tid=6 idx 104607–104612) Pure `RtlEnterCriticalSection`+`RtlLeaveCriticalSection` import/kernel.call/ kernel.return triples on canary's side. Return values all `0x00000000` (uncontended fast-path). **No handles referenced.** Not wedge-relevant by construction — these are CS API calls, not signal-flow events. ### Wait-begin (1 event, canary tid=6 idx 104622) ``` SID: a25a16a4f6f547aa (object_type=1 EVENT) raw_handle_id: 0xf8000044 (canary kernel-table slot) created at: canary tid=10 idx=843 (worker thread) used by: 108 wait.begin events across canary tids 6, 9, 10, 17, 18 ``` **Embedded inside an `RtlEnterCriticalSection` block** (idx 104620 import.call → 104621 kernel.call → 104622 wait.begin → 104623 kernel.return). This is canary's CS slow-path — the CS was contended so the wait.begin fired on the **CS dispatcher Event**. Object_type=1 (EVENT) is the Xbox kernel's representation of the CS's owned-by-other-thread dispatcher; NOT a user-mode `NtCreateEvent`-created Event. The Event is created on worker tid=10 because in canary the worker did run and contend on this CS. In ours the workers don't run so the CS is never contended; ours fast-paths through (uncontended kernel.return at idx 104616 with status 0). **Wedge handles in ours** (per `halt-on-deadlock-dump.txt`) are: `0x12d0`, `0x1020`, `0x1040`, `0x10b0`, `0x10ec`, `0x12e4` — all `object_type=1 EVENT` but all created via `NtCreateEvent` at `LR=0x824a9f6c` from worker tid=13. They're worker-LOCAL Events (SIDs `d5e23609d3948568` etc., computed from ours's per-tid recipe), NOT the shared CS dispatcher Event `a25a16a4f6f547aa`. **Verdict**: absorber is correctly suppressing CS-contention scheduling jitter, not wedge signal flow. The Event canary waits on is the CS dispatcher proxy, never the user-mode worker-private Events. ### Shared-global (1 event, ours tid=10 idx 2) ``` SID: ac8315b371bcf7cb (object_type=3 SEMAPHORE) raw_handle_id: 0x828a3230 (guest VA — well-known XAudio voice-volume semaphore, documented in C+18) ``` ours emits `handle.create` for this Semaphore at idx 2 because `ensure_dispatcher_object` synthesizes the shadow KernelObject at first touch (Phase C+17). Canary doesn't emit a corresponding `handle.create` on the same tid pair because the canary first toucher was a different host thread — classic process-global first-toucher race that C+18 was specifically designed for. **Wedge handles are all EVENT (object_type=1).** This is a SEMAPHORE (type=3). Different object class, different code path (XAudio voice volume). Not wedge-relevant. **Verdict**: absorber is correctly suppressing first-toucher race for a shared XAudio dispatcher, not wedge signal flow. ## Selective-disable matched-prefix deltas Baseline (all absorbers ON): main tid=6→1 matched=**105,128**. | disabled absorber | main matched | delta | sister 15→10 matched | |---|---|---|---| | (none — baseline) | 105,128 | 0 | 16 | | shared-global | 105,128 | 0 | 2 (−14) | | wait-begin | 104,616 | −512 | 16 | | nested-cs | 104,607 | −521 | 16 | The delta pattern matches the absorbed events exactly: - nested-cs's 6 absorbed events at idx 104,607–104,612 enabled the 104,607 → 105,128 advance (combined with subsequent wait-begin). - wait-begin's single absorb at idx 104,622 enabled the 104,616 → 105,128 advance (without it, the absorber-chain stops there). - shared-global's single absorb on tid=15→10 enabled that sister chain's 2 → 16 advance. ## Cross-reference verdict **None of the absorbed events reference a wedge-relevant handle.** Specifically: 1. Nested-cs absorbs RtlEnter/Leave **API events** — no handles involved. 2. Wait-begin absorbs a CS-dispatcher Event used in CS contention. The wedge Events are user-mode `NtCreateEvent` outputs from worker tid=13 — DIFFERENT object class than CS dispatchers. 3. Shared-global absorbs an XAudio SEMAPHORE — wedge handles are all EVENT type. ## What the absorbers DO reveal indirectly The wait-begin and nested-cs absorbers fire because canary's main thread (tid=6) waits on a CS that ours never contends on. **The reason ours never contends on it is because the worker cluster (canary tid=9/10/14/15/17/18) never runs** — they emit 17 and 77 events in ours (vs 995k and 1.9M in canary) per Phase W ground truth. The absorbers are therefore CORRECTLY treating the contention pattern as scheduling jitter at the diff layer. The underlying root cause — workers don't bootstrap — is what Phase W identified and is unchanged by absorber behavior. Even if we disabled all three absorbers, the surfaced divergences would be: - canary's main waiting on a CS dispatcher that ours doesn't create (because the contending worker is absent), AND - canary's main entering CS nested-cleanup branches because the CS-protected registry has more entries (because workers inserted them). Both are downstream effects of the same upstream "workers don't run" root cause that Phase D's contention-replay (Stage 3/4) and quantum (Stage 0) experiments already failed to unblock. No new signal-flow gap is exposed.