Unclear why policy is proposed for emulation of read-only sstateen.

[kasanovic]

"Bit 63 of each mstateen CSR may be read-only zero only if the hypervisor extension is not implemented and the matching supervisor-level sstateen CSR is all read-only zeros. In that case, machine-level software should emulate attempts to access the affected sstateen CSR from S-mode, ignoring writes and returning zero for reads. Bit 63 of each hstateen CSR is always writable (not read-only)."

Not clear why mstateen would have bit 63 clear, then emulate sstateen being read-only zero when the condition stated is that sstateen already exists as read-only zero CSR. Suggest dropping emulation suggestion and moving to non-normative text.