Open-IOV vGPU-IO: host-side GSP emulation for unmodified NVIDIA guest drivers https://git.vgpu.io/open-iov.git/atom?h=master 2026-10-14T15:39:30+00:00 2026-10-14T15:39:30+00:00 Arthur Hanson Rasmusson arthur@vgpu.io 2026-10-14T15:39:30+00:00 urn:sha1:624438bb0901680f416b879727b30a411dd3d78b The guest PMA scrubber (in-guest CeUtils CE channel, 4096 GPFIFO entries) waits on its channel buffer's finish payload (offset 0x6c004) after the third CUDA session's pages must be scrubbed; nothing in the emulation authored it, so cudaMalloc froze in scrubCheckAndWaitForSize. - channel_add: detect the 4096-entry scrubber channel and stash its USERD PA/ring geometry (the channel itself is left untouched: no rank change, no pump change - the colliding numeric-handle FREE may still unregister it, the geometry survives). - sema_scrubbuf_add debug param: register the finish/host-semaphore word PAs the guest scanner resolves (vmallocinfo + kcore walk), because the RM kernel VA space collides numerically with the client CE window in the global VA map and cannot be resolved through it. - svc_scrub_pass (service thread, per pass): from the channel's own USERD GPPut, track submitted scrub blocks across wraps, then author USERD GP_GET = put, host semaphore = put and finish payload = submitted. Forward-only, idempotent, zero writes while the scrubber idles. Live-validated mechanism (r137 VM): authoring the finish word at the kcore- resolved PA let the frozen victory_matmul leave scrubCheckAndWaitForSize and proceed to its launch.