XSA-351 causing Solaris-11 systems to panic during boot.

[Cheyenne Wills <cheyenne.wills@xxxxxxxxx>]

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.