Simple, kernel-only, 64bit OS, early stage. https://git.2137697.xyz/rs-dos/atom?h=qemu 2026-11-01T15:33:09Z 2026-11-01T15:33:09Z salmonik salmonik@tuta.io 2026-11-01T15:33:09Z urn:sha1:363e24bcd18a28948f63fa78ac8a4eaa8784fe59 - test-usb boots an EHCI and an xHCI controller with a mouse + keyboard and asserts enumeration, report decoding, and input reaching the shell. The EHCI case asserts one key end-to-end (QEMU's EHCI model delivers only the first report through root-port split transactions); the xHCI case asserts a whole typed command. - lib.sh: qemu_args() already supplies -bios, so the fresh OVMF varstore copy was silently overridden by the system firmware. Pass the copy last (QEMU honours the last -bios) so tests really boot clean NVRAM. - DEBUG_NOTES: document why USB never worked on the OptiPlex (EHCI shipped with DEBUG_MATRIX enabled, no RMH/hub support, only the first controller, no boot protocol, unbounded DMA), the success/failure log to look for on hardware, and the QEMU coverage limits. - Makefile: add test-usb and include it in `make test`.