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Date:   Wed, 4 Sep 2019 09:58:03 -0700
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Jim Mattson <jmattson@google.com>
Cc:     Krish Sadhukhan <krish.sadhukhan@oracle.com>,
        kvm list <kvm@vger.kernel.org>,
        Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH 2/4] KVM: nVMX: Check GUEST_DR7 on vmentry of nested
 guests
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On Wed, Sep 04, 2019 at 09:44:58AM -0700, Jim Mattson wrote:
> On Tue, Sep 3, 2019 at 5:59 PM Krish Sadhukhan
> <krish.sadhukhan@oracle.com> wrote:
> > Is it OK to keep this Guest check in software for now and then remove it
> > once we have a solution in place ?
> 
> Why do you feel that getting the priority correct is so important for
> this one check in particular? I'd be surprised if any hypervisor ever
> assembled a VMCS that failed this check.

Agreed.  I don't see much value in adding a subset of guest state checks,
and adding every check will be painfully slow.  IMO we're better off
finding a solution that allows deferring guest state checks to hardware.