RHBA-2009:0966 - Bug Fix Advisory

Topic

An updated kernel-utils package that fixes various bugs and adds
enhancements is now available.

Description

The kernel-utils package provides kernel-related support utilities, such as
CPU frequency scaling support, processor microcode updates, and a DMI
decoding utility.

This updated package fixes the following bugs:

• irqbalance distributes interrupt load evenly across CPUs. On systems with

a sufficiently large number of CPUs, irqbalance would cause a segmentation
fault because the utility assumed that there would be no more than 1024
bytes in any line of /proc/interrupts. With a sufficiently large number of
CPUs, lines could exceed the arbitrary 1024-byte limit and irqbalance could
not then parse them correctly. Furthermore, irqbalance was limited to
support no more than 256 IRQs. The version of irqbalance provided by this
update assumes no upper limit on the length of lines in /proc/interrupts,
and increases the number of IRQs supported to 512. (BZ#474893)

As well, this updated package adds the following enhancements:

• cpuspeed dynamically changes the speed of CPUs that are capable of being

scaled. Previously, users of certain multi-core systems in the IBM
x3[n]50 family could encounter a situation where cores were throttled back
by cpuspeed even while the core was under heavy load. This would have a
severe negative impact on the performance of the system. The problem would
occur when cpuspeed detected that the load on any one core had dropped to a
point where it could be throttled back. Cpuspeed would then throttle back
all the cores regardless of the load on them. Cpuspeed relies on a kernel
module not supplied with Red Hat Enterprise Linux 4 (affected_cpus) to
identify cores that must be scaled individually. Without this module,
cpuspeed must launch a separate process for each core that is to be
throttled separately. The version of cpuspeed supplied with this advisory
uses the affected_cpus module if it is available, allows users to manually
specify a cpu group, but otherwise forks a separate process for each core.
Users of multi-core systems can now use cpuspeed without the utility
scaling cores based on the load experienced by other cores. (BZ#451119,
BZ#497490)

• smartmontools now support new CCISS controllers found, for example, in

newer HP ProLiant servers. (BZ#447979)

• this version of kernel-utils updates the Intel microcode file to version

20080910, to support newer Intel processors. (BZ#453642)

• dmidecode gives information about BIOSes and motherboard revisions. The

version of kernel-utils supplied with this advisory updates dmidecode from
version 2.2 to version 2.9. This version identifies newer processors,
PCI-express slots and devices, and blade chassis. It also offers enhanced
support for the SMBIOS v2.6 specification. (BZ#459041)

Users of kernel-utils are advised to upgrade to this updated package, which
resolves these issues and adds these enhancements.

Solution

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

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 4 x86_64
• Red Hat Enterprise Linux Server 4 ia64
• Red Hat Enterprise Linux Server 4 i386
• Red Hat Enterprise Linux Workstation 4 x86_64
• Red Hat Enterprise Linux Workstation 4 ia64
• Red Hat Enterprise Linux Workstation 4 i386
• Red Hat Enterprise Linux Desktop 4 x86_64
• Red Hat Enterprise Linux Desktop 4 i386
• Red Hat Enterprise Linux for IBM z Systems 4 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390
• Red Hat Enterprise Linux for Power, big endian 4 ppc

Fixes

• BZ - 447979 - smartmontools doesn't work well with CCISS
• BZ - 459041 - update dmidecode from 2.2 to 2.9, the latest version
• BZ - 474893 - irqbalance segfaults on systems with large # of cores
• BZ - 497490 - CPU's freq keep on being maximum even though they are idle

CVEs

(none)

References

(none)