The pciback_enable_msi function in the PCI backend driver (drivers/xen/pciback/conf_space_capability_msi.c) in Xen for the Linux kernel 2.6.18 and 3.8 allows guest OS users with PCI device access to cause a denial of service via a large number of kernel log messages. NOTE: some of these details are obtained from third party information.
http://lists.opensuse.org/opensuse-security-announce/2013-03/msg00004.html
http://lists.opensuse.org/opensuse-security-announce/2013-04/msg00018.html
http://lists.opensuse.org/opensuse-security-announce/2013-06/msg00005.html
http://secunia.com/advisories/52059
https://exchange.xforce.ibmcloud.com/vulnerabilities/81923