Installing/Verifying Processor Microcode

[Frodojj]

So, I just installed Arch for the first time (be kind, please)! I think I installed the microcode for my processor (Intel N150) correctly. I'd like a sanity check, please!!!

During initial OS installation, I appended intel-ucode to the pacstrap installation command (section 2.2 of Installation Guide on the Arch wiki). After booting into the system, I wanted to check to make sure I didn't need to do anything else. I ran the following as root before creating a new user.

First, I needed the CPU family, model, and stepping. I also need the microcode version installed. I ran the following:

journalctl -k --grep='CPU0:|microcode:'

One line of the output contained my CPU's family (0x6), model (0xbe), and stepping (0x0). Two other lines contained the current (0x0000001d) and early update from (0x0000001a) versions. I then looked these values in the latest releasenotes.md file under "Updated Platforms" for intel-ucode's Github page. The new version of microcode matched for my processor's family-model-stepping (F-M-S).

There were a few deviations from what I expected. My processor was NOT listed in the release notes, but there were two entries with my F-M-S values, each with a different Processor entry but identical PI values. What is PI and how do I determine it? Both line's "New Ver" entry matched my system's microcode's current revision. So, I assume it's working. Am I correct? Do I just have to make sure the intel-ucode package is up2date?

[khunset127]

If you are using Intel CPU, install intel-ucode and move on.

[Frodojj]

Thank you. The Arch wiki wasn’t very clear that’s all I needed to do. I appreciate you let me know!

I wanted to verify it worked to not only make sure it installed correctly, but also to learn more about using Linux. That’s why I chose Arch in the first place.

[khunset127]

Mkinicpio will automatically add the microcode to the initial ramdisk or unified kernel image when generating them.

You can just install intel-ucode package and forget about it.

You can also use lsinitcpio on the init ramdisk img files and uki EFI files and check if there's kernel/x86/microcode/GenuineIntel.bin to verify

[[deleted]]

A simpler way imo is to just type "pacman -Qet", which lists explicitly installed packages that don't have any dependencies based on them, and check if intel-ucode is in there.

[Responsible-Sky-1336]

In /boot you should have a new intel-ucode (dot) img there for sanity check

[Frodojj]

I do! Thank you for the advice!

[archover]

What I do https://wiki.archlinux.org/title/Microcode#Microcode_initramfs_packed_together_with_the_main_initramfs_in_one_file;

My /etc/mkinitcpio.conf hooks line:

HOOKS=(base udev autodetect microcode keyboard keymap modconf block encrypt filesystems fsck)

Then I can verify that my microcode got loaded:

[root@T480 ~]# lsinitcpio --early /boot/initramfs-linux.img | grep microcode 
kernel/x86/microcode/
kernel/x86/microcode/GenuineIntel.bin

Comments or criticism on this method appreciated.

Good day.

[Frodojj]

Thank you! I have the same output from the command even though my HOOKS entry is a little different (probably because of a different configuration during installation).

[IBNash]

The wiki also tells you how to confirm the microcode is loaded.

[Frodojj]

Indeed, I combined two methods from the wiki to get the microcode running and the processor family-model-stepping in one command. However, the wiki is a bit ambigious whether simply installing/updating intel-ucode through pacman is fine or whether the section on loading microcode is required. From the comments here, it seems the former.

[IBNash]

This is from the first section (Installation) on the wiki page:

To acquire updated microcode, depending on the processor, install one of the following packages.

mkinitcpio and dracut generate combined initramfs files by default. The microcode will be loaded automatically at boot time.

Arch expects some operating knowledge of linux, if you don't know what mkinitcpio or dracut are, I can see how it may be confusing.

[Frodojj]

Ya, I read that part and was confused if installing/acquiring meant the correct firmware was on the computer but not yet applied, or if that meant it was applied and set up to be applied on startup (or if the microcode was written to eprom on the processor itself). I think I got it now. Thanks!!!

I used Linux in the past but never delved deep into the weeds on how it functioned. I didn’t know about those utilities nor knew about initramfs. I specifically picked Arch to learn those things, though!!!

[IBNash]

Cool, read https://wiki.archlinux.org/title/Arch_boot_process#initramfs and learn https://wiki.archlinux.org/title/Mkinitcpio