On 05/05/20 23:15, John Hauser wrote:

- attempts to execute WFI, unless the instruction completes within an
implementation-specific, bounded time;

It would be great to have this controlled by a bit in the hstatus CSR.
For example a hypervisor that does not overcommit CPUs will probably
want to delegate WFI to the guest. Guest-delegated interrupts then
would not incur the overhead of world switching, while host-handled
interrupts would exit to the hypervisor anyway.

(It may even make sense to add this to mstatus, but I wouldn't care much
about it right now except perhaps when choosing which bit to use in
hstatus).

Paolo