The ssm_i emulation in Xen 5.1 on IA64 architectures allows attackers to cause a denial of service (dom0 panic) via certain traffic, as demonstrated using an FTP stress test tool.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10226
https://exchange.xforce.ibmcloud.com/vulnerabilities/41633
http://www.securityfocus.com/bid/29085