wasm: make virtio console handoff explicit and reset-safe - #44
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The host previously delivered stdin as soon as receive descriptors appeared, but Linux queues those descriptors before the console port is connected and intentionally discards data received in that window. Single-port virtio-console provides no guest-open notification, so descriptor availability is not a sufficient readiness signal. Advertise a one-port multiport console and gate input on the guest PORT_OPEN message. Implement the DEVICE_READY, PORT_ADD, PORT_READY, CONSOLE_PORT, RESIZE, and PORT_OPEN state machine synchronously, including scatter/gather control buffers and multiport resize notifications. No timers or pacing are used. Also propagate virtio reset from the wasm transport to host devices. Packed queues are invalidated so stale chains and pending kicks cannot survive reset, while console and network backends retain host-side pending data for restored guest queues. Validation: - TypeScript checks - 14/14 device tests, repeated ten times - immediate launch-time stdin and virtiofs shares integration tests - runner lifecycle suite - 60/60 four-CPU lifecycle stress runs, plus three- and eight-CPU smoke tests Agent-Session: codex:019fe115-244a-76c1-b716-b8af6827da00
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The host previously delivered stdin as soon as receive descriptors appeared, but Linux queues those descriptors before the console port is connected and intentionally discards data received in that window. Single-port virtio-console provides no guest-open notification, so descriptor availability is not a sufficient readiness signal.
Advertise a one-port multiport console and gate input on the guest PORT_OPEN message. Implement the DEVICE_READY, PORT_ADD, PORT_READY, CONSOLE_PORT, RESIZE, and PORT_OPEN state machine synchronously, including scatter/gather control buffers and multiport resize notifications. No timers or pacing are used.
Also propagate virtio reset from the wasm transport to host devices. Packed queues are invalidated so stale chains and pending kicks cannot survive reset, while console and network backends retain host-side pending data for restored guest queues.
Validation:
Agent-Session: codex:019fe115-244a-76c1-b716-b8af6827da00