RHBA-2015:1309 - Bug Fix Advisory

Topic

Updated crash packages that fix several bugs and add various enhancements are
now available for Red Hat Enterprise Linux 6.

Description

The crash packages provide the core analysis suite, which is a self-contained
tool that can be used to investigate live systems, as well as kernel core dumps
created by the kexec-tools packages or the Red Hat Enterprise Linux kernel.

The crash packages have been upgraded to upstream version 7.1.0, which provides
a number of bug fixes and enhancements over the previous version. (BZ#1111357)

This update also fixes the following bugs:

• A prior update of the AMD64 and Intel 64 kernels removed the STACKFAULT

exception stack. As a consequence, using the "bt" command with the updated
kernels previously displayed an incorrect exception stack name if the backtrace
originated in an exception stack other than STACKFAULT. In addition, the "mach"
command displayed incorrect names for exception stacks other than STACKFAULT.
This update ensures that stack names are generated properly in the described
circumstances, and both "bt" and "mach" now display correct information.
(BZ#1179480)

• Attempting to run the crash utility with the vmcore and vmlinux files

previously caused crash to enter an infinite loop and became unresponsive. With
this update, the handling of errors when gathering tasks from pid_hash[] chains
during session initialization has been enhanced. Now, if a pid_hash[] chain has
been corrupted, the patch prevents the initialization sequence from entering an
infinite loop. This prevents the described failure of the crash utility from
occurring. In addition, the error messages associated with corrupt or invalid
pid_hash[] chains have been updated to report the pid_hash[] index number.
(BZ#1208557)

• On certain system configurations, the "kmem -f", "kmem -F", and "kmem

[address]" command options previously took a very long time to complete. This
update increases the internal hash queue size used to store the address of each
free page, and streamlines the free page search to only check the NUMA node that
contains a specified address. As a result, the mentioned "kmem" options no
longer have a negative impact on performance. (BZ#1073987)

In addition, this update adds the following enhancement:

• The makedumpfile command now supports the new sadump format that can represent

more than 16 TB of physical memory space. This allows users of makedumpfile to
read dump files over 16 TB, generated by sadump on certain upcoming server
models. (BZ#1195596)

Users of crash 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 Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 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 Power, big endian 6 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 Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

• BZ - 1073987 - crash-7.0.1-0.1.x86_64 built on RHEL6.4 system hung for 4 hours consuming CPU on ~2GB x86_64 vmcore
• BZ - 1179480 - crash "bt" command mislabels exception stacks on x86_64 kernels which have no STACKFAULT stack
• BZ - 1208557 - crash-7.1.0-1.el6 spins at 'please wait... (gathering task table data)' when loading rhel6.4.z vmcore

CVEs

(none)

References

(none)