Issued:

2011-12-21

Updated:

2011-12-21

RHBA-2011:1846 - kernel bug fix update

Synopsis

kernel bug fix update

Type/Severity

Bug Fix Advisory (none)

Topic

Updated kernel packages that fix two bugs are now available for Red Hat Enterprise Linux 6 Extended Update Support.

Description

The kernel packages contain the Linux kernel, the core of any Linux operating system.

This update fixes the following bugs:

• Previously, the idle_balance() function dropped or retook the rq->lock parameter, leaving the previous task vulnerable to the set_tsk_need_resched() function. Now, the parameter is cleared in setup_thread_stack() after a return from balancing and no successfully descheduled or never scheduled task has it set, thus fixing this bug. (BZ#751995)

• A software bug related to Context Caching existed in the Intel IOMMU support module. On some newer Intel systems, the Context Cache mode has changed from previous hardware versions, potentially exposing a Context coherency race. The bug was exposed when performing a series of hot plug and unplug operations of a Virtual Function network device which was immediately configured into the network stack, i.e., successfully performed dynamic host configuration protocol (DHCP). When the coherency race occurred, the assigned device would not work properly in the guest virtual machine. With this update, the Context coherency is corrected and the race and potentially resulting device assignment failure no longer occurs. (BZ#757670)

All users of kernel are advised to upgrade to these updated packages, which fix these bugs. The system must be rebooted for this update to take effect.

Solution

Before applying this update, make sure all previously-released errata relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at This content is not included.https://access.redhat.com/kb/docs/DOC-11259

Affected Products

Updated Packages

• kernel-2.6.32-131.22.1.el6.i686.rpm
• perf-2.6.32-131.22.1.el6.i686.rpm
• kernel-debug-devel-2.6.32-131.22.1.el6.s390x.rpm
• kernel-2.6.32-131.22.1.el6.ppc64.rpm
• kernel-debug-2.6.32-131.22.1.el6.i686.rpm
• kernel-firmware-2.6.32-131.22.1.el6.noarch.rpm
• kernel-debuginfo-common-i686-2.6.32-131.22.1.el6.i686.rpm
• perf-debuginfo-2.6.32-131.22.1.el6.ppc64.rpm
• kernel-2.6.32-131.22.1.el6.x86_64.rpm
• perf-debuginfo-2.6.32-131.22.1.el6.x86_64.rpm
• kernel-kdump-devel-2.6.32-131.22.1.el6.s390x.rpm
• kernel-debug-2.6.32-131.22.1.el6.s390x.rpm
• perf-2.6.32-131.22.1.el6.s390x.rpm
• kernel-headers-2.6.32-131.22.1.el6.ppc64.rpm
• kernel-devel-2.6.32-131.22.1.el6.x86_64.rpm
• kernel-bootwrapper-2.6.32-131.22.1.el6.ppc64.rpm
• kernel-debug-debuginfo-2.6.32-131.22.1.el6.ppc64.rpm
• kernel-debuginfo-common-s390x-2.6.32-131.22.1.el6.s390x.rpm
• kernel-debug-2.6.32-131.22.1.el6.ppc64.rpm
• kernel-devel-2.6.32-131.22.1.el6.ppc64.rpm
• perf-debuginfo-2.6.32-131.22.1.el6.s390x.rpm
• kernel-2.6.32-131.22.1.el6.src.rpm
• kernel-debug-devel-2.6.32-131.22.1.el6.i686.rpm
• kernel-devel-2.6.32-131.22.1.el6.i686.rpm
• kernel-debuginfo-2.6.32-131.22.1.el6.i686.rpm
• kernel-debuginfo-common-ppc64-2.6.32-131.22.1.el6.ppc64.rpm
• kernel-headers-2.6.32-131.22.1.el6.i686.rpm
• kernel-debug-devel-2.6.32-131.22.1.el6.ppc64.rpm
• kernel-2.6.32-131.22.1.el6.s390x.rpm
• kernel-headers-2.6.32-131.22.1.el6.s390x.rpm
• kernel-debuginfo-2.6.32-131.22.1.el6.x86_64.rpm
• kernel-debug-2.6.32-131.22.1.el6.x86_64.rpm
• kernel-devel-2.6.32-131.22.1.el6.s390x.rpm
• kernel-debug-devel-2.6.32-131.22.1.el6.x86_64.rpm
• kernel-headers-2.6.32-131.22.1.el6.x86_64.rpm
• kernel-debug-debuginfo-2.6.32-131.22.1.el6.s390x.rpm
• kernel-debuginfo-2.6.32-131.22.1.el6.s390x.rpm
• perf-2.6.32-131.22.1.el6.x86_64.rpm
• kernel-debuginfo-common-x86_64-2.6.32-131.22.1.el6.x86_64.rpm
• kernel-kdump-debuginfo-2.6.32-131.22.1.el6.s390x.rpm
• kernel-kdump-2.6.32-131.22.1.el6.s390x.rpm
• kernel-debug-debuginfo-2.6.32-131.22.1.el6.x86_64.rpm
• perf-2.6.32-131.22.1.el6.ppc64.rpm
• perf-debuginfo-2.6.32-131.22.1.el6.i686.rpm
• kernel-doc-2.6.32-131.22.1.el6.noarch.rpm
• kernel-debug-debuginfo-2.6.32-131.22.1.el6.i686.rpm
• kernel-debuginfo-2.6.32-131.22.1.el6.ppc64.rpm

Fixes

(none)

CVEs

(none)

References

(none)

Additional information

• The Red Hat security contact is This content is not included.secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.
• Offline Security Data data is available for integration with other systems. See Offline Security Data API to get started.