RHBA-2011:0956 - Bug Fix Advisory

Topic

Updated kernel packages that fix three bugs are now available for Red Hat
Enterprise Linux 5.4 Extended Update Support.

Description

The kernel packages contain the Linux kernel, the core of any Linux operating
system.

This update fixes the following bugs:

• The timer_interrupt() routine did not scale lost real ticks to logical ticks

correctly. This could have caused time drift for 64-bit Red Hat Enterprise Linux
5: KVM (Kernel-based Virtual Machine) guests that were booted with the
"divider=x" kernel parameter set to a value greater than 1. "warning: many lost
ticks" messages may have been logged on the affected guest systems. (BZ#711792)

• Prior to this update, the time_stamp could be incorrectly checked before it

was set if the transmission update set the time_stamp after the Direct Memory
Access (DMA) pointer. Due to this race condition, the completed transmission
detecting function wrongly sent a message that the transmission was unresponsive
and the transmission stopped. This update ensures that first the time_stamp is
updated and then the DMA pointer. Now, the time_stamp no longer appears stale
when data is actually being transmitted. (BZ#711841)

• Under certain circumstances, a crash in the kernel could occur due to a race

condition in the lockd_down function, which did not wait for the lockd process
to come down. With this update, the lockd_down function has been fixed, and the
kernel no longer crashes. (BZ#714729)

All users are advised to upgrade to these updated 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 for x86_64 - Extended Update Support 5.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 i386
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 5.4 s390x
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.4 ppc

Fixes

• BZ - 714729 - [5.6][REG]for some uses of 'nfsservctl' system call, the kernel crashes.

CVEs

(none)

References

(none)