To find out the current status of microcode:
Run the following command as root user:
# dmesg | grep microcode
Please note that it is entirely possible that there is no microcode update available for your CPU. In that case, it will look as follows:
[ 0.952699] microcode: sig=0x306a9, pf=0x10, revision=0x1c [ 0.952773] microcode: Microcode Update Driver: v2.2.
How to install Intel microcode firmware on Linux using a package manager
Tool to transform and deploy CPU microcode update for x86/amd64 comes with Linux. The procedure to install AMD or Intel microcode firmware on Linux is as follows:
1) Open the terminal app.
2) Debian/Ubuntu Linux user type: "sudo apt install intel-microcode".
3) CentOS/RHEL Linux user type: "sudo yum install microcode_ctl".
4)You must reboot the box to activate micocode update.
5)Verify it after reboot.
How to install Intel processor microcode blob for Linux (20180108 release)
Ok, first visit AMD or Intel site to grab the latest microcode firmware. In this example, I have a file named ~/Downloads/microcode-20180108.tgz (don’t forget to check for checksum) that suppose to help with meltdown/Spectre. First, extract it using the tar command:
$ mkdir firmware
$ cd firmware
$ tar xvf ~/Downloads/microcode-20180108.tgz
$ ls -l
Make sure /sys/devices/system/cpu/microcode/reload exits:
$ ls -l /sys/devices/system/cpu/microcode/reload
You must copy all files from Intel-ucode to /lib/firmware/intel-ucode/ using the cp command:
$ sudo cp -v intel-ucode/* /lib/firmware/intel-ucode/
You just copied the intel-ucode directory to /lib/firmware/. Write the reload interface to 1 to reload the microcode files:
# echo 1 > /sys/devices/system/cpu/microcode/reload
Update an existing initramfs so that next time it gets loaded via kernel:
$ sudo update-initramfs -u
$ sudo reboot
Verifying that microcode got updated on boot or reloaded by echo command:
# dmesg | grep microcode
That's all!!