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Date:   Fri, 31 Jan 2020 10:55:32 -0800
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Paul Mackerras <paulus@ozlabs.org>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Janosch Frank <frankja@linux.ibm.com>,
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Subject: Re: [PATCH 5/5] KVM: x86: Set kvm_x86_ops only after
 ->hardware_setup() completes
Message-ID: <20200131185531.GB18946@linux.intel.com>
References: <20200130001023.24339-1-sean.j.christopherson@intel.com>
 <20200130001023.24339-6-sean.j.christopherson@intel.com>
 <44e0c550-7dcc-bfed-07c4-907e61d476a1@redhat.com>
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On Thu, Jan 30, 2020 at 06:44:09AM +0100, Paolo Bonzini wrote:
> On 30/01/20 01:10, Sean Christopherson wrote:
> > Set kvm_x86_ops with the vendor's ops only after ->hardware_setup()
> > completes to "prevent" using kvm_x86_ops before they are ready, i.e. to
> > generate a null pointer fault instead of silently consuming unconfigured
> > state.
> 
> What about even copying kvm_x86_ops by value, so that they can be
> accessed with "kvm_x86_ops.callback()" and save one memory access?

Oooh, I like that idea.  And {svm,vmx}_x86_ops could be marked __initdata
to save a few bytes and force all the runtime stuff through kvm_x86_ops.