RHBA-2011:1044 - Bug Fix Advisory

Topic

Updated systemtap packages that fix several bugs are now available for Red Hat
Enterprise Linux 5.

Description

SystemTap is an instrumentation system for systems running the Linux kernel. The
system allows developers to write scripts to collect data on the operation of
the system.

This update fixes the following bugs:

• Previously, the buildok/fortyfive.stp test case failed to build with SystemTap

on the Itanium systems. The problem has been fixed in this update. (BZ#559599)

• Previously, the systemtap service was not stopped and restarted after the

"service systemtap stop" and "service systemtap restart" commands were issued.
Instead, the service only stopped and was not restarted. This update fixes the
problem so that the systemtap service now behaves as expected. (BZ#607232)

• Previously, there was a timing issue when running the "service systemtap

restart" command in that a test case for the systemtap-initscript package
sometimes failed to restart the service when a script was running. This issue
has been resolved with this update so that the command runs correctly now.
(BZ#644350)

• After prelink had been run on a system based on the i686 platform, using

SystemTap user-space probes that targeted functions or statements in certain
shared libraries, or executables based on a separate debuginfo file, caused
resolution to the wrong PC location in a linked binary. As a result, the
intended probes failed to fire at the correct place in the program, which could
have caused the program to crash or misbehave due to a corrupted instruction
sequence resulting from incorrect breakpoint insertions. With this update, the
libdwfl library code (the libdw.so shared object library) was adjusted to use a
more reliable method of compensating for prelink's effect on the address layout
of a binary when aligning a runtime PC address with an address computed
separately from the separated debuginfo file. SystemTap probes should now work
the same on prelinked binaries as they would on binaries that have not been
prelinked. (BZ#646870)

• On the i386 platform, there was a semantic error found in the

buildok/scheduler-ctxswitch.stp test case, which limited SystemTap's testsuite
and tapset portability. This update fixes the problem. (BZ#661424)

• Previously, an itrace (process("PROC").insn) probe could have resulted in a

kernel panic as a result of an incorrect PID being used when setting up the
probe. The problem has been fixed in this update so that the probe no longer
results in a kernel panic. (BZ#699342)

All users requiring SystemTap are advised to upgrade to these updates packages,
which fix these bugs.

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

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 IBM z Systems 5 s390x
• 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 - 559599 - Errata testing: buildok/fortyfive.stp FAIL (ia64)
• BZ - 607232 - Stopped systemtap initscript does not start on 'restart'
• BZ - 644350 - Timing issue in systemtap initscript restart command
• BZ - 646870 - misaddresed user-space probes on prelinked shared libraries on i686 (REL)

CVEs

(none)

References

(none)