Comment 8 for bug 1157757

It looks like with this specific setup (using xm because of libvirt, and that because to enable the use of libxl in libvirt the packaging in xen has to change to include all required parts in libxen-dev) the problem is that the code in newer Xen versions that would filter SMEP only works if HAP is used (which is not). But somehow despite the comment in the code saying something else, Xen always seems to be in paging mode, even if the guest VCPU is not. This makes me think that maybe the check should only rely on !hvm_paging_enabled(v). Using this patch on the xen source prevents the hangs.