Updated microcode_ctl packages that fix one bug and add one enhancement are now available for Red Hat Enterprise Linux 6.
The microcode_ctl packages provide utility code and microcode data to assist the kernel in updating the CPU microcode at system boot time. This microcode supports all current x86-based, Intel 64-based, and AMD64-based CPU models. It takes advantage of the mechanism built-in to Linux that allows microcode to be updated after system boot. When loaded, the updated microcode corrects the behavior of various processors, as described in processor specification updates issued by Intel and AMD for those processors.
Previously, the microcode_ctl utility did not detect if it was running in a virtual machine and attempted to install the CPU microcode updates. This behavior caused several errors to be returned in the kernel ring buffer. The underlying source code has been modified and microcode_ctl no longer tries to update the CPU microcode in the described scenario.
- BZ#915957, BZ#1005606
The Intel CPU microcode file has been updated to version 20130906.
All users of microcode_ctl are advised to upgrade to these updated packages, which fix this bug and add this enhancement. Note: a system reboot is necessary for this update to take effect.