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Date:   Thu, 4 Jun 2020 11:46:56 -0700
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Jim Mattson <jmattson@google.com>
Cc:     kvm list <kvm@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Liran Alon <liran.alon@oracle.com>,
        Oliver Upton <oupton@google.com>,
        Peter Shier <pshier@google.com>
Subject: Re: [PATCH v3 3/4] kvm: vmx: Add last_cpu to struct vcpu_vmx
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On Wed, Jun 03, 2020 at 01:18:31PM -0700, Jim Mattson wrote:
> On Tue, Jun 2, 2020 at 7:24 PM Sean Christopherson
> <sean.j.christopherson@intel.com> wrote:
> > As an alternative to storing the last run/attempted CPU, what about moving
> > the "bad VM-Exit" detection into handle_exit_irqoff, or maybe a new hook
> > that is called after IRQs are enabled but before preemption is enabled, e.g.
> > detect_bad_exit or something?  All of the paths in patch 4/4 can easily be
> > moved out of handle_exit.  VMX would require a little bit of refacotring for
> > it's "no handler" check, but that should be minor.
> 
> Given the alternatives, I'm willing to compromise my principles wrt
> emulation_required. :-) I'll send out v4 soon.

What do you dislike about the alternative approach?