Red Hat ENTERPRISE 5.4 RELEASE NOTES, Manual

Page: 148 / 466

Chapter 1. Package Updates
130
• An optimization error was found in
linux-2.6-misc-utrace-update.patch
. When running
32-bit processes on a 64-bit machine systems didn't return ENOSYS errors on missing (out of table
range) system calls. This kernel release includes a patch to correct this. (
BZ#481682
929
)
• Some cluster systems where found to boot with an unstable time source. It was determined that this
was a result of kernel code not checking for a free performance counter (
PERFCTR
) when calibrating
the TSC (Time Stamp Clock) during the boot process. This resulted, in a small percentage of cases,
in the system defaulting to a busy
PERFCTR
and getting unreliable calibrations.
A fix was implemented to correct this by ensuring the system checked for a free
PERFCTR
before
defaulting (
BZ#467782
930
). This fix, however, cannot satisfy all possible contingencies as it is
possible that all
PERFCTR
s will be busy when required for TSC calibration. Another patch has been
included to initiate a kernel panic in the unlikely event (fewer than 1% of cases) that this scenario
occurs. (
BZ#472523
931
).
1.110.9.7.3. PPC
Kernel updates for PowerPC architectures.
• This kernel release includes various patches to update the
spufs
(Synergistic Processing Units file
system) for Cell processors. (
BZ#475620
932
)
• An issue was identified wherein
/proc/cpuinfo
would list logical PVR Power7 processor
architecture as "unknown" when
show_cpuinfo()
was run. This update adds a patch to have
show_cpuinfo()
identify Power7 architectures as Power6. (
BZ#486649
933
)
• This update includes several patches that are required to add/improve
MSI-X
(Message Signaled
Interrupts) support on machines using System P processors. (
BZ#492580
934
)
• A patch has been added to this release to enable the functionality of the previously problematic
power button on Cell Blades machines. (
BZ#475658
935
)
1.110.9.7.4. S390
Kernel updates for S390 architectures.
• Utilizing Named Saved Segments (NSS), the z/VM hypervisior makes operating system code in
shared real memory pages available to z/VM guest virtual machines. With this update, Multiple Red
Hat Enterprise Linux guest operating systems on the z/VM can boot from the NSS and be run from a
single copy of the Linux kernel in memory. (
BZ#474646
936
)
• Device driver support has been added in this update for the new IBM System z PCI cryptography
accelerators, utilizing the same interfaces as prior versions. (
BZ#488496
937
)
• Control Program Identification (CPI) descriptive data is used to identify individual systems on the
Hardware Management Console (HMC). With this update, CPI data can now be associated with a
Red Hat Enterprise Linux instance. (
BZ#475820
938
)
• Fibre Channel Protocol (FCP) performance data can now be measured on Red Hat Enterprise Linux
instances on the IBM System z platform. (
BZ#475334
939
). Metrics that are collected and reported n
include:
• Performance relevant data on stack components such as Linux devices, Small Computer System
Interface (SCSI) Logical Unit Numbers (LUNs) and Host Bus Adapter (HBA) storage controller
information.