Arch Linux

Captain Athelas

Member

Registered: 2020-05-15

Posts: 33

CPU microcode is not applied

I just noticed that microcode patches (amd-ucode) are not being applied on my system. I use systemd-boot.

# journalctl -k --grep=microcode
mrt 03 20:54:25 [REDACTED] kernel: Zenbleed: please update your microcode for the most optimal fix
mrt 03 20:54:25 [REDACTED] kernel: microcode: Current revision: 0x08701021

I have "systemd-boot-update.service" enabled. Also:

# bootctl update
Skipping "/boot/EFI/systemd/systemd-bootx64.efi", same boot loader version in place already.
Skipping "/boot/EFI/BOOT/BOOTX64.EFI", same boot loader version in place already.

In "/boot/loader/entries/arch.conf" (only file here):

title	Arch Linux
linux	/vmlinuz-linux
initrd	/amd-ucode.img
initrd	/initramfs-linux.img
options root="UUID=[REDACTED]" rw

I don't understand why it's not working. Anyone else know what the issue is?

Scimmia

Fellow

Registered: 2012-09-01

Posts: 11,592

Re: CPU microcode is not applied

Unless you're on a server/datacenter processor, chances of getting ucode updates from the amd-ucode package are pretty much non-existent.

Captain Athelas

Member

Registered: 2020-05-15

Posts: 33

Re: CPU microcode is not applied

So I should just ignore this?

Scimmia

Fellow

Registered: 2012-09-01

Posts: 11,592

Re: CPU microcode is not applied

You get updates from your motherboard maker, so check there first. There are people that have extracted the microcode from their firmware, see https://aur.archlinux.org/packages/amd- … e-platomav

Captain Athelas

Member

Registered: 2020-05-15

Posts: 33

Re: CPU microcode is not applied

I have updated the motherboard, but it didn't change anything. I'll guess it's okay.

agapito

Member

From: Who cares.

Registered: 2008-11-13

Posts: 662

Re: CPU microcode is not applied

I have updated the motherboard, but it didn't change anything. I'll guess it's okay.

That's because no manufacturer has yet released a bios that includes the microcode fix for Zenbleed.

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Excuse my poor English.

webcapcha

Member

Registered: 2019-02-14

Posts: 136

Re: CPU microcode is not applied

You get updates from your motherboard maker, so check there first.

Do you mean update UEFI?

Unless you're on a server/datacenter processor, chances of getting ucode updates from the amd-ucode package are pretty much non-existent.

Wait, does it mean the amd-ucode package do nothing?

Previously I had Intel cpu where ucode was applied, Is that AMD specific or maybe bad configs after all?

❯ sudo journalctl -k --grep=microcode
[sudo] password for lex:
Mar 22 07:17:07 lenovo-laptop kernel: Speculative Return Stack Overflow: IBPB-extending microcode not applied!
Mar 22 07:17:07 lenovo-laptop kernel: Speculative Return Stack Overflow: Vulnerable: Safe RET, no microcode
Mar 22 07:17:07 lenovo-laptop kernel: microcode: Current revision: 0x0a704101

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Ukrainian

nl6720

The Evil Wiki Admin

Registered: 2016-07-02

Posts: 599

Re: CPU microcode is not applied

Wait, does it mean the amd-ucode package do nothing?

For consumer AMD Ryzen CPUs it currently does nothing. It's still useful for other (older or server) AMD CPUs.