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Date:   Tue, 17 Sep 2019 15:28:18 -0700
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Marc Orr <marcorr@google.com>
Cc:     kvm@vger.kernel.org, Jim Mattson <jmattson@google.com>,
        Peter Shier <pshier@google.com>,
        Krish Sadhukhan <krish.sadhukhan@oracle.com>
Subject: Re: [kvm-unit-tests PATCH v3 2/2] x86: nvmx: test max atomic switch
 MSRs
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On Tue, Sep 17, 2019 at 01:16:27PM -0700, Marc Orr wrote:
> > > +     /* Cleanup. */
> > > +     vmcs_write(ENT_MSR_LD_CNT, 0);
> > > +     vmcs_write(EXI_MSR_LD_CNT, 0);
> > > +     vmcs_write(EXI_MSR_ST_CNT, 0);
> > > +     for (i = 0; i < cleanup_count; i++) {
> > > +             enter_guest();
> > > +             skip_exit_vmcall();
> > > +     }
> >
> > I'm missing something, why do we need to reenter the guest after setting
> > the count to 0?
> 
> It's for the failure code path, which fails to get into the guest and
> skip the single vmcall(). I've refactored the code to make this clear.
> Let me know what you think.

Why is not entering the guest a problem?