RHBA-2011:1032 - Bug Fix Advisory

Topic

Updated device-mapper-multipath packages that fix several bugs and add various
enhancements are now available for Red Hat Enterprise Linux 5.

Description

The device-mapper-multipath packages provide tools to manage multipath devices
using the device-mapper multipath kernel module.

This update fixes the following bugs:

• Prior to this update, when viewing partition information from a file, kpartx

used a loop device which was not released by kpartx afterwards. With this
update, this erroneous behavior has been fixed so that kpartx now correctly
releases a loop device as expected. (BZ#578109)

• After a thread of the multipathd service acquired its resource locks, the

thread did not check if it had been canceled before accessing the resource. This
caused multipathd to occasionally terminate unexpectedly with a segmentation
fault on shutdown if the thread attempted to access the resource after the
thread was canceled. With this update, the bug has been fixed so that the
multipathd thread now checks if it is canceled before accessing its resource.
(BZ#639429)

• When the multipathd service started, it created a separate namespace for

itself, and unmounted all unnecessary disk-backed file systems. Since /ram file
systems are not considered to be disk-backed, they should have not been
unmounted by multipathd, however multipathd unmounted them. This update corrects
this undesired behavior so that the /ram file systems are no longer unmounted.
(BZ#663179)

• Prior to this update, the multipathd service did not check if a value was

entered for an option in the /etc/multipath.conf configuration file before
attempting to read the value. As a result, multipathd terminated unexpectedly
when an option without any value was found in /etc/multipath.conf. With this
update, the bug has been fixed so that multipathd no longer crashes. (BZ#675369)

• If the last path of a device was deleted while the multipathd service was

trying to reload the device map, or if a ghost path failed, multipathd did not
always switch into recovery mode. As a result, multipath devices were not able
to recover I/O operations in setups that were supposed to temporarily queue I/O
if all paths were unavailable. This update resolves both of these problems;
multipath now correctly recovers I/O operations as configured. (BZ#677821)

• Prior to this update, there was a spelling mistake found in the "invalid

keyword" error message. The spelling mistake has been fixed in this update.
(BZ#676165)

As well, this update adds the following enhancements:

• This update introduces two new defaults options in the /etc/multipath.conf

configuration file: "fast_io_fail_tmo" and "dev_loss_tmo". The
"fast_io_fail_tmo" option controls how long the SCSI layer waits after a SCSI
device fails before failing back the I/O. This option can be set to "off" or any
number less than the "dev_loss_tmo" option. The "dev_loss_tmo" option controls
how long the SCSI layer waits after a SCSI device fails before marking it as
failed. The default values for these options are set by the SCSI device drivers.
(BZ#672575)

• This update introduces a new defaults section parameter for the

/etc/multipath.conf configuration file: the "file_timeout" parameter. This
parameter controls how many seconds the multipathd service will wait for a
necessary file to appear while setting up a multipath device. The default value
is 90 seconds. (BZ#627911)

• This update introduces the default configuration for multiple new HP storage

array products. (BZ#502813)

All users of device-mapper-multipath should 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.

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 - 578109 - kpartx doesn't release it's loop devices
• BZ - 627911 - wait_for_file() times out on the environment with a large number of multipath devices and high load.
• BZ - 639429 - multipathd segfaults due to shutdown race
• BZ - 675369 - multipathd segfault if no "LUN wwid" value is present with keyword "wwid"
• BZ - 676165 - Typo in multipath output, "mulipath.conf line 17, invalid keyword:"
• BZ - 677821 - multipathd occassionally doesn't stop queuing after no_path_retry times out.

CVEs

(none)

References

(none)