RHEA-2015:0881 - Product Enhancement Advisory

Topic

Updated devtoolset-3-systemtap packages that fix several bugs and add various
enhancements are now available for Red Hat Developer Toolset 3.1.

Description

SystemTap is an instrumentation system for systems running the Linux kernel,
which allows developers to write scripts to collect data on the operation of the
system. The devtoolset-3-systemtap packages provide the Red Hat Developer
Toolset version of SystemTap.

The devtoolset-3-systemtap packages have been upgraded to upstream version 2.6,
which provides a number of bug fixes and enhancements over the previous version.

The SystemTap front end (stap) has been improved in a number of ways:

• A new option, "-E <script>", has been added, which allows for specifying

additional scripts. Note that a main script still needs to be specified with the
"-e" option or in a file.

• DWARF process probes can now be bound to a specific process using the

following syntax:

process(<PID>).function("*")

• SystemTap now supports probes with the following syntax:

process("<PATH>").library("<PATH>").plt("<NAME>").return

• A PID provided for a process probe is now expected by SystemTap to correspond

to a running process.

• Probes are now printed in a more consistent and precise manner when the

listing mode is invoked using the "-l" or "-L" options.

• Enumerated line numbers are now supported by statement probes, which allows

for probing discontiguous lines. Use the following syntax:

process.statement("<example@file.c>:<3,5-7,9>")

• SystemTap now supports moving a probe from the specified line to the nearest

line that can be probed using the following syntax:

statement("<*@file>:<NUM>").nearest

The SystemTap runtime back end (staprun) has been improved in a number of ways:

• Certain probe types, kprobes, uprobes, and timer.*s(<NUM>), can now be armed

and disarmed on the fly. Thus, probe overhead can be avoided when probes are not
needed.

• Non-recursive and loop-free probes now have statement counting suppressed in

the generated C code. Counting can be turned back on in the unoptimized mode by
using the "-u" option with the stap command.

• Statically Defined Tracing (SDT) probes with operands that refer to symbols

are now supported.

Multiple new functions have been added to the tapset library and many tapsets
were simplified by using the new autocast feature.

(BZ#1121363, BZ#1172775, BZ#1172781)

Users of devtoolset-3-systemtap are advised to upgrade to these updated
packages, which fix these bugs and add these enhancements.

Solution

Before applying this update, make sure all previously released errata relevant
to your system have been applied.

For details on how to apply this update, refer to:

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

Affected Products

• Red Hat Software Collections (for RHEL Server) 1 for RHEL 7 x86_64
• Red Hat Software Collections (for RHEL Server) 1 for RHEL 6.6 x86_64
• Red Hat Software Collections (for RHEL Server) 1 for RHEL 6.5 x86_64
• Red Hat Software Collections (for RHEL Server) 1 for RHEL 6 x86_64
• Red Hat Software Collections (for RHEL Workstation) 1 for RHEL 7 x86_64
• Red Hat Software Collections (for RHEL Workstation) 1 for RHEL 6 x86_64
• Red Hat Software Collections (for RHEL Server) from RHUI 1 for RHEL 7 x86_64
• Red Hat Software Collections (for RHEL Server) from RHUI 1 for RHEL 6 x86_64

Fixes

• BZ - 1172775 - dereferencing pointer to incomplete type struct knfsd_fh
• BZ - 1172781 - nfs3_proc_read_setup: unable to find local 'data'

CVEs

(none)

References

(none)