kernel security update

kernel:
[2.6.18-308.8.2.el5]

• [xen] x86_64: check address on trap handlers or guest callbacks (Paolo Bonzini) [813430 813431] {CVE-2012-0217}
• [xen] x86_64: Do not execute sysret with a non-canonical return address (Paolo Bonzini) [813430 813431] {CVE-2012-0217}
• [xen] x86: prevent hv boot on AMD CPUs with Erratum 121 (Laszlo Ersek) [824969 824970]
  ocfs2:
  [1.4.10]
• ocfs2/dlm: Cleanup mlogs in dlmthread.c dlmast.c and dlmdomain.c
• ocfs2/dlm: make existing convertion precedent over new lock
• ocfs2/dlm: Cleanup dlmdebug.c
• ocfs2/dlm: Minor cleanup
• ocfs2/dlm: Hard code the values for enums
• ocfs2: Wakeup down convert thread just after clearing OCFS2 LOCK UPCONVERT FINISHING
• ocfs2/dlm: Take inflight reference count for remotely mastered resources too
• ocfs2/dlm: dlmlock remote needs to account for remastery
• ocfs2: Add some trace log for orphan scan
• ocfs2: Remove unused old id in ocfs2_commit_cache
• ocfs2: Remove obsolete comments before ocfs2_start_trans
• ocfs2: Initialize the bktcnt variable properly and call it bucket_count
• ocfs2: Use cpu to le16 for e leaf clusters in ocfs2_bg_discontig_add_extent
• ocfs2: validate bg free bits count after update
• ocfs2: cluster Pin the remote node item in configfs
• ocfs2: Release buffer head in case of error in ocfs2_double_lock
• ocfs2: optimize ocfs2 check dir entry with unlikely() annotations
• ocfs2: Little refactoring against ocfs2 iget
• ocfs2: Initialize data ac might be used uninitializ
• ocfs2 Skip mount recovery for hard ro mounts
• ocfs2: make direntry invalid when deleting it
• ocfs2: commit trans in error
• ocfs2: Fix deadlock when allocating page
• ocfs2: Avoid livelock in ocfs2 readpage