On Tue, Feb 16, 2021 at 04:59:52PM +0100, Paolo Bonzini wrote:
> - the inner handler does nothing but telling the outer handler to rerun.
> The way it does it is certainly not pretty, because it has to work at any
> instruction boundary, but at its heart it's basically a do{}while loop.
That only works if processing of all inner #VE can be deferred, which is
not the case for instruction emulation #VEs like MSR accesses, io-port
or MMIO accesses. I guess those could all be replaced direct TDCALLs,
but the question remains whether this is possible with MSR accesses, means
that the list of MSRs which will cause #VEs is statically defined and
doesn't change between hypervisors. All in all this sounds hard to
maintain and easy to break by unrelated changes.
Regards,
Joerg
