BITS

Tool from Intel called “BIOS Implementation Test Suite”. Bootable (usb) image which can do several things including handling microcode:

• https://biosbits.org
• https://github.com/biosbits/bits
• https://github.com/mkorthof/bits

Linux

load/update microcode using pkg:

Debian

• Intel: apt install intel-microcode iucode-tool
• AMD: apt install amd64-microcode
• Doc: /usr/share/doc/{intel,amd64}-microcode/README.Debian.gz

CentOS/RH

• microcode_ctl
• https://git.centos.org/summary/rpms!microcode_ctl.git

load/update intel microcode manually:

• get latest tgz from intel: see below
• backup/copy files: /lib/firmware/intel-ucode
• check kernel config: grep MICROCODE /boot/config-*
• run iucode_tool:
  /usr/sbin/iucode_tool -tb -lS /lib/firmware/intel-ucode/*
• update initramfs: update-initramfs -u -k all

reloading microcode:

• echo 1 > /sys/devices/system/cpu/microcode/reload
• or: rmmod cpuid; modprobe cpuid

show version:

• dmesg | grep microcode
• grep microcode /proc/cpuinfo

skip loading microcode on boot:

• add to grub cmdline: dis_ucode_ldr

Windows

Microsoft includes microcode updates in Windows for certain CPU’s. For example: KB4090007, KB3064209, KB2970215.

load/update microcode:

• using a VMWare driver called “cpumcupdate”: https://labs.vmware.com/flings/vmware-cpu-microcode-update-driver

show version:

• get hwinfo64 and goto “Central Processor(s)” > “Microcode Update Revision”
• or get “Read & Write Everything” (RWEverything) from http://rweverything.com

Get Microcode

Download the latest version from Intel:
https://downloadcenter.intel.com/download/27431/Linux-Processor-Microcode-Data-File?v=t.