Re: [PATCH RFC hack dont apply] intel_idle: support running within a VM

Rafael J. Wysocki
2017-09-29T23:21:46Z

On Sat, Sep 30, 2017 at 12:01 AM, Michael S. Tsirkin <mst@redhat.com> wrote:
> intel idle driver does not DTRT when running within a VM:
> when going into a deep power state, the right thing to
> do is to exit to hypervisor rather than to keep polling
> within guest using mwait.
>
> Currently the solution is just to exit to hypervisor each time we go
> idle - this is why kvm does not expose the mwait leaf to guests even
> when it allows guests to do mwait.
>
> But that's not ideal - it seems better to use the idle driver to guess
> when will the next interrupt arrive.

The idle driver alone is not sufficient for that, though.

Thanks,
Rafael