Security update for xen (important)

Xen was updated to 4.3.4 to fix multiple vulnerabities and non-security
bugs.

The following vulnerabilities were fixed:

• Long latency MMIO mapping operations are not preemptible (XSA-125
  CVE-2015-2752 bnc#922705)
• Unmediated PCI command register access in qemu (XSA-126 CVE-2015-2756
  bnc#922706)
• Hypervisor memory corruption due to x86 emulator flaw (bnc#919464
  CVE-2015-2151 XSA-123)
• Information leak through version information hypercall (bnc#918998
  CVE-2015-2045 XSA-122)
• Information leak via internal x86 system device emulation (bnc#918995
  (CVE-2015-2044 XSA-121)
• HVM qemu unexpectedly enabling emulated VGA graphics backends
  (bnc#919663 CVE-2015-2152 XSA-119)
• information leakage when guest sets high resolution (bnc#895528
  CVE-2014-3615)

The following non-security bugs were fixed:

• L3: XEN blktap device intermittently fails to connect (bnc#919098)
• Problems with detecting free loop devices on Xen guest startup
  (bnc#903680)
• xentop reports "Found interface vif101.0 but domain 101 does not exist."
  (bnc#861318)
• Intel ixgbe driver assigns rx/tx queues per core resulting in irq
  problems on servers with a large amount of CPU cores (bnc#901488)
• SLES11 SP3 Xen VT-d igb NIC doesn’t work (bnc#910254)