Synopsis

kernel bug fix update

Type/Severity

Bug Fix Advisory

Topic

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

Description

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

This update fixes the following bugs:

• Previously, the bonding driver did not support TCP segmentation offloading

(TSO). As a consequence, the performance decreased significantly, and the
"ethtool -k bondX" command reported that the TSO was disabled, although the
slave device had the TSO enabled. The following message appeared in the kernel
log: "Dropping TSO features since no CSUM". The problem affected also bridges
and loopback interfaces. The underlying source code has been modified to ensure
that the bonding module does not drop TSO features for NO_CSUM devices. As a
result, the aforementioned performance problem no longer occurs. (BZ#1037812)

• There was an error in the tag insertion logic, and bonding handled cases when

a slave device did not have a hardware VLAN acceleration. As a consequence, the
network packets were tagged twice through slave devices without hardware VLAN
tag insertion, and two Solarflare network cards using bonding over a VLAN did
not work properly. This update removes the redundant VLAN tag insertion logic,
and the unwanted behavior no longer occurs. (BZ#1039562)

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
https://access.redhat.com/site/articles/11258

To install kernel packages manually, use "rpm -ivh [package]". Do not use "rpm

• Uvh" as that will remove the running kernel binaries from your system. You may

use "rpm -e" to remove old kernels after determining that the new kernel
functions properly on your system.

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.5 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.5 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.5 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.5 i386
• Red Hat Enterprise Linux EUS Compute Node 6.5 x86_64
• Red Hat Enterprise Linux Server - AUS 6.5 x86_64
• Red Hat Enterprise Linux Server - TUS 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

CVEs

(none)

References