That said, I don’t know whether Theo has since “eaten crow” or has otherwise personally evolved.
And even smart people can be wrong. Sometimes a lot.
The Xen hypervisor itself was pretty minimal, as I understand mostly serving to time-slice CPU cycles among guest domains and partition memory access. As a contrast to VMWare, device access and drivers were handled by the guests themselves.
As such, the attack surface of the Xen hypervisor itself is fairly minimal. Most security issues seem to be denial of service vulnerabilities, though there are some privilege escalation, access, information leak, and overflow issues listed:
<https://xenbits.xen.org/xsa/>
I generally respect de Raadt's expertise and instincts, though he may have been over his skis here.
AMD released (ie commercially available) Pacifica on May 23, 2006 while Intel did released their Vanderpool a half of year earlier November 14, 2005. [0]
Windows Server 2008 was RTM'ed on February 2008 which provided Hyper-V as a first class component. [1]
Virtual Server 2005 R2 SP1 added support for both Intel VT (IVT) and AMD Virtualization (AMD-V) and was released 11 June 2007. [2]
https://en.wikipedia.org/wiki/X86_virtualization#AMD_virtual...
https://en.wikipedia.org/wiki/Windows_Server_2008
https://en.wikipedia.org/wiki/Microsoft_Virtual_Server#Versi...