# legacy-driver-guest — historical guest-side driver (NOT BUILT)

This directory preserves the **old guest-side vGPU driver** (`gsp-vgpu.ko`)
from the pre-refactor architecture, where GSP RPC handling lived in a kernel
module *inside the guest*.

It is kept for reference only:

- The current architecture is **host-only GSP emulation** — the guest runs
  the stock, unmodified `nvidia.ko`, and there is no Open-IOV code in the
  guest. See `docs/GSP_EMULATION_ARCHITECTURE.md`.
- Nothing here is part of any build target (the top-level Makefile no longer
  references it).
- `kernel-tests/` holds the old test modules written against this driver's
  internal API (`gsp_core.h`); they are superseded by
  `kernel/tests/gsp_emulation_test.c`, which tests the host-side emulation
  engine through `gsp_emu_process_rpc()`.

Do not add new code here. If you need behavior that only exists in this tree
(e.g. WPR eventfd work, migration WPR state), port it into the host-side
`kernel/` modules rather than reviving the guest driver.