Re: [PATCH 6/9] KVM: x86: Provide paravirtualized flush_tlb_multi()

From: Andy Lutomirski
Date: Wed Jun 26 2019 - 14:22:12 EST


On Wed, Jun 26, 2019 at 10:41 AM Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> wrote:
>
> Andy Lutomirski <luto@xxxxxxxxxx> writes:
>
> > All this being said, do we currently have any system that supports
> > PCID *and* remote flushes? I guess KVM has some mechanism, but I'm
> > not that familiar with its exact capabilities. If I remember right,
> > Hyper-V doesn't expose PCID yet.
> >
>
> It already does (and support it to certain extent), see
>
> commit 617ab45c9a8900e64a78b43696c02598b8cad68b
> Author: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> Date: Wed Jan 24 11:36:29 2018 +0100
>
> x86/hyperv: Stop suppressing X86_FEATURE_PCID
>

Hmm. Once the dust settles from Nadav's patches, I think we should
see about supporting it better :)