RHBA-2008:0419 - Bug Fix Advisory

Topic

An updated irqbalance package that fixes various bugs is now available.

Description

irqbalance is a daemon that evenly distributes IRQ load across multiple
CPUs for enhanced performance.

This updated package fixes the following bugs:

• when reading the topology information from /sys/devices/system/cpu,

irqbalance only checked for the sub-string "cpu". This caused it to try to
open nonsense files such as /sys/devices/system/cpu/cpuidle/online. On
further investigation, it was discovered this bug also caused irqbalance to
not access files post startup. As well, code inefficiencies were found. In
this update, irqbalance reads the /sys/devices/system/cpu hierarchy
properly, ensuring nonsense files are not opened and allowing access to
files after startup. The uncovered inefficiencies have also been corrected
(eg a new string is no longer created for each "getline" call).

• when variables in the export statements of the irqbalance init script

were not set, all exported variables were printed to the console. This is
both unnecessary and not compliant with the Linux Standard Base (LSB)
specification. This update corrects this and the irqbalance init script is
now LSB-compliant.

This update also adds the following enhancement:

• three irqbalance environment variables -- BANNED_CPU, AFFINITY_MASK and

BANNED_INTERRUPT -- are now properly documented in the irqbalance man page.
As well, their functionality is now exposed via the sysconfig file.

All irqbalance users should upgrade to this updated package which addresses
this issues and add this enhancement.

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/FAQ_58_10188

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 242477 - Wrong init script
• BZ - 311341 - Incorrect CPU topology parsing
• BZ - 432977 - Error in /etc/init.d/irqbalance results in potential misconfiguration and screen garbage

CVEs

(none)

References

(none)