From 01994e83c3754c98c065489daabd980fa001d5ba Mon Sep 17 00:00:00 2001 From: Arthur Hanson Rasmusson Date: Sat, 17 Oct 2026 00:26:17 -0400 Subject: STATE-CURRENT: pinpoint the stall - cudaEventSynchronize after a default-stream record never completes (minimal repro); host event post path still fails with EINVAL; sema side verified healthy at the stall; cross-boot matrix r177-r179 --- STATE-CURRENT.md | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'STATE-CURRENT.md') diff --git a/STATE-CURRENT.md b/STATE-CURRENT.md index a79d5f2..5322e98 100644 --- a/STATE-CURRENT.md +++ b/STATE-CURRENT.md @@ -273,6 +273,21 @@ isolation, performance, portability). that does not land where the launch's data fill later reads the operand (the vidmem write path vs the fill's read path divergence; analysis and the ranked ledger fix are in the private handoff, cont. 23). + **Update 2026-10-17 ~01:00 (stall pinpointed on r179; diagnostics only, no tree change yet):** + a minimal repro (`cudaEventCreate` + `cudaEventRecord` on the default stream + + `cudaEventSynchronize`) sits forever after the record - the first CUDA call pinned down + as a hard hang. A 3-stream workload using event record/wait/elapsed time stalls even as + the very first client of a fresh boot (intrinsic, not position- or poison-dependent; + unclean client kills were tested and do not break the next client). On a used boot the + user's `victory_mail`/`victory_matmul` hit the same wait: the client spins in driver + userspace while a background worker polls the interrupt-service RM control once per + second. The host's event-registration table and post path exist (register on NV01_EVENT + alloc, retire on free, per-channel/all post helpers) and the stall windows still show + frequent post failures with EINVAL; the host sema side is verified healthy at the stall + (client pushes decode, pool releases apply to the correct page, then the machine idles). + Cross-boot matrix: mail/matmul/smiley green early; strided/atomics/memset2d/saxpy fail + fast on the remaining data class at any position; event-sync stalls always. Next: fix + the completion post so the recorded event wakes (details in the private handoff, cont. 24). **Update 2026-10-16 ~18:40 (reliability wave m160-m162 + harness fixes; verified battery, no reboots):** five cycles (r163-r167) landed and verified the bounds of the earlier "STATUS FAIL / freeze" repro. Fixed and live-verified across boots: `victory_mail` and -- cgit v1.2.3