The linux-firmware packages contain all of the firmware files that are required by various devices to operate. This update supersedes microcode provided by Red Hat with the CVE-2017-5715 CPU branch injection vulnerability mitigation. Further testing has uncovered problems with the microcode provided along with the Spectre mitigation that could lead to system instabilities. As a result, Red Hat is providing an microcode update that reverts to the last known good microcode version dated before 03 January 2018. Red Hat strongly recommends that customers contact their hardware provider for the latest microcode updates. IMPORTANT: Customers using Intel Skylake-, Broadwell-, and Haswell-based platforms must obtain and install updated microcode from their hardware vendor immediately. The Spectre mitigation requires both an updated kernel from Red Hat and updated microcode from your hardware vendor.