Running Xen with XSA-351 is causing Solaris 11 systems to panic during boot. The panic screen is showing the failure to be coming from "unix:rdmsr". The panic occurs with existing guests (booting off a disk) and the booting from an install ISO image.
I discussed the problem with "andyhhp__" in the "#xen" IRC channel and he requested that I report it here. This was failing on a Xen 4.13 and a Xen 4.14 system built via gentoo. I understand that ultimately this is a bug in Solaris. However it does impact existing guests that were functional before applying the XSA-351 security patches.
