kvm: nVMX: Set VM instruction error for VMPTRLD of unbacked page
It is never correct for a VMX instruction to fail with "invalid VMCS"
if there is, in fact, a current VMCS. Reads from unbacked addresses
return all 1's, which means that an unbacked VMCS will not have the
correct VMCS revision ID (i.e. VMCS12_REVISION).
Fixes: 0b3f16e4a905b ("KVM: nVMX: Implement VMPTRLD") Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>