Xen was updated to fix security issues and bugs.

Update to bug fix release Xen 4.3.2 c/s 27404

- CVE-2013-6885: xen: XSA-82: A guest triggerable
AMD CPU erratum may cause host hangs.

- CVE-2013-6400: xen: XSA-80: IOMMU TLB flushing may be inadvertently
suppressed, potentially leaking information to other guests.

- CVE-2013-2212: xen: XSA-60: Excessive time to disable caching with
HVM guests with PCI passthrough

- pygrub: Support (/dev/xvda) style disk specifications