RHBA-2012:0063 - Bug Fix Advisory

Topic

Updated kernel packages that fix multiple bugs and add one enhancement are now
available for Red Hat Enterprise Linux 5 Extended Update Support.

Description

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

This update fixes the following bugs:

• The kdump service did not work properly with some HP Smart Array controllers

and could fail to create a core dump file or could become unresponsive under
certain circumstances. This update provides multiple bug fixes and changes for
the cciss driver and thus ensures that kdump works as expected with most HP
Smart Array controllers.

On a Red Hat Enterprise Linux 5.6 system, it is advisable to update the firmware
of the HP ProLiant Generation 6 (G6) controller (which includes: P410i, P411,
P212, P712, and P812) to version 5.02 or later. After the successful firmware
update, reboot the system and kdump will work as expected.

However, kdump may still fail when using the HP Smart Array 5i Controller on a
Red Hat Enterprise Linux 5.6 system. (BZ#749187)

• When the SMP (Symmetric Multi Processing) kernel ran the crash_kexec()

function, the local Advanced Programmable Interrupt Controllers (APICs) could
have pending interrupt requests (IRQs) in their vector tables. If there was more
than one pending IRQ within the same 32-bit word in the Local APIC (LAPIC)
vector table registers, the I/O APIC subsystem would enter setup with pending
interrupts left in the LAPIC, causing various degrees of malfunctioning
depending on the stuck interrupt vector. This update adds the MAX_LOOPS
parameter to limit number of iterations and to provide enough time for the
pending IRQs to be cleared if the loop was to lock-up. (BZ#756943)

• The IDE error handling code uses the IDE interrupt handler and the general

interrupt handler. This could lead to the erroneous execution of kexec/kdump
code that was intended to only run at boot time. As a result, the asserted IDE
IRQ line would be cleared without the interrupt being handled, which in turn
caused the system to become unresponsive during the shut down of the kexec/kdump
kernel. To fix this bug, a new test for the IRQ status, which should be
IRQ_DISABLED, has been introduced to ensure that the code introduced for the
kexec/kdump kernel only executes at boot time. (BZ#759386)

• When kdump was triggered under a heavy load, the system became unresponsive

and failed to capture a crash dump. This update fixes interrupt handling for
kdump so that kdump successfully captures a crash dump while under a heavy load.
(BZ#761535)

• When a device triggered an interrupt request (IRQ) during kdump kernel

startup, the kernel tried to process the IRQ even though the respective
interrupt handler was not loaded. As a consequence, the kernel could not finish
its startup and the system became unresponsive. This update allows the kernel to
disable the IRQ line if the kernel receives a large number of IRQs and there is
no interrupt handler loaded in the kernel. The kernel now starts as expected and
kdump can successfully create a core dump. (BZ#761539)

In addition, this update adds the following enhancement:

• This update provides the latest cciss driver. The driver now allows the kernel

to wait for a reasonable amount of time after PCI Power Management resets a
CCISS device so the device can be properly detected. (BZ#758021)

All users are advised to upgrade to these updated packages, which fix these bugs
and add this enhancement. 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/kb/docs/DOC-11259

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 for x86_64 - Extended Update Support 5.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.6 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.6 i386
• Red Hat Enterprise Linux Server - AUS 5.6 x86_64
• Red Hat Enterprise Linux Server - AUS 5.6 ia64
• Red Hat Enterprise Linux Server - AUS 5.6 i386
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 5.6 s390x
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.6 ppc
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 5.6 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 5.6 i386

Fixes

CVEs

(none)

References

(none)