Re: [PATCH] KVM: VMX: Enable Notify VM exit

[Xiaoyao Li]

On 11/3/2020 2:25 AM, Paolo Bonzini wrote:
> On 02/11/20 19:01, Andy Lutomirski wrote:
> > What's the point?  Surely the kernel should reliably mitigate the
> > flaw, and the kernel should decide how to do so.
>
> There is some slowdown in trapping #DB and #AC unconditionally.  Though
> for these two cases nobody should care so I agree with keeping the code
> simple and keeping the workaround.

OK.

> Also, why would this trigger after more than a few hundred cycles,
> something like the length of the longest microcode loop?  HZ*10 seems
> like a very generous estimate already.

As Sean said in another mail, 1/10 tick should be a placeholder.
Glad to see all of you think it should be smaller. We'll come up with 
more reasonable candidate once we can test on real silicon.