Re: [PATCH 12/13] KVM: x86: Replace late check_nested_events() hack with more precise fix

From: Sean Christopherson
Date: Wed Apr 29 2020 - 12:45:50 EST


On Wed, Apr 29, 2020 at 10:36:17AM +0200, Paolo Bonzini wrote:
> On 29/04/20 00:20, Sean Christopherson wrote:
> >> So, that's what this mess was all about! Well, this certainly looks better.
> > Right? I can't count the number of times I've looked at this code and
> > wondered what the hell it was doing.
> >
> > Side topic, I just realized you're reviewing my original series. Paolo
> > commandeered it to extend it to SVM. https://patchwork.kernel.org/cover/11508679/
>
> If you can just send a patch to squash into 9/13 I can take care of it.

Ugh, correctly prioritizing SMI is a mess. It has migration implications,
a proper fix requires non-trivial changes to inject_pending_event(), there
are pre-existing (minor) bugs related to MTF handling, and technically INIT
should have lower priority than non-trap exceptions (because the exception
happens before the event window is opened).

Can you just drop 9/13, "Prioritize SMI over nested IRQ/NMI" from kvm/queue?
It's probably best to deal with this in a new series rather than trying to
squeeze it in.