Microcode for every processor? Not a Xeon 5650?

[npaust]

Somehow, in my decade of using gentoo, I completely missed the fact that I need to include microcode in my kernel. I guess it's really more of an optimization than a need!

Anyway, I followed the instructions on the Intel Microcode wiki and got 5 of my 6 machines working. The last one though is failing because I can't find the microcode for the processor.

The processor in question is a Intel Xeon x5650 with a signature of x206c2. If you look at the Intel documentation pages, the 20150121 microcode package specifically references this processor. However, when I emerge that package, there's no microcode with that signature.

Is this normal? Do I have a perfect processor that's never needed revisions? Is the microcode package in portage defective and missing my processor? Or, is there some simple thing that I'm just overlooking?

Thanks for enlightening me,
Nathaniel

[Roman_Gruber]

There is always a microcode update regardless if you want itor not. UEFI does it for you during booting. and the operating system does it during bootup.

at genreation 4xxx processors onward this has to be done in linux with the initramfs in your bootloader. no more loading as in ivybridge or before when linux is already loaded.

have you checked dmesg what it says ?

--

Sigh I wish guys would crasp, that gentoo stable means "outdated" as debian stable.

[npaust]

That only sort of answers my question. It appears that there is no specific microcode update for this processor (no updates with the correct signature) in either the Intel downloads or in the gentoo package. dmesg does show that the microcode uses some revision, but that's apparently coming from the computer's bios rather than from linux.

Also, your mention of needing to use an initramfs to do early loading of microcode is outdated. In recent kernels, I'm still at 4.4.39, you can add the microcode right into the kernel and it correctly updates at the start of the boot process.

[Roman_Gruber]

[frostschutz]

I don't know if that Xeon Whatever has a microcode udpate.

If Linux updated the microcode correctly, it will be the first line even before the kernel reports its version.

[npaust]

Roman_Gruber, at the bottom of the intel microcode wiki page it has a description of how to use the microcode without an initramfs. It may not be hugely functionally different, but from my point of view it's fairly simple. If there was some user that was scared off by having to set up the initramfs, it's good to know that that step isn't required. The change date on that wiki is from the end of December 2016, so it may be that that's a fairly recent change.

I think we're getting away from my original question, which more academic than functional. There isn't a specific file in the intel releases that corresponds to my processor on one of my machines. That machine has been fairly rock solid for the ~5 years that I've had it (and I've never worried about microcode issues before). So, in large part the question is simply, "If you can't find a microcode file for your processor, does it really matter?"

For completeness though, the machine is a Dell and does have the most recent bios installed. I don't care enough to try to figure out what particular microcode the bios may or may not be trying to load. Using the gentoo-sources-4.4.39 kernel, and without inserting a specific microcode file, dmesg does not show any lines of "microcode updated early". Since I'm not specifying a microcode, that would really surprise me. I'm also not particularly inclined to jump to a different kernel just to play with an issue that seems to be a non-issue.

Again though, it seems like the answer is that you should go looking for microcode for your processor if you're running into problems. If a machine works, then the bios or some other behind-the-scenes method is taking care of it.

[Roman_Gruber]

Just for information. early_ucode.cpio is my generated intel microcode. initramfs-genkernel-x86_64-4.2.3-gentoo is the genkernel geneated initramfs.

[hmh]

[npaust]

hmh, thank you for that detailed explanation. I'm guessing that this computer would be your worst nightmare since dmesg reports an 0x10 revision on the microcode. I wish I had a history of what versions of the microcode that Dell has pushed out in previous BIOS updates. I wonder if they went backwards to specifically avoid some of the issues you outlined?

Anyway, the computer is a desktop workstation, not a server, and doesn't run any virtualization, isn't using TXT, and only connects to the world via ssh anyway. In the past ~5 years of use (it is getting close to retirement), it's had perhaps two crashes, even with being on and used 24/7. My usage patterns must just not hit the bugs.

Thanks for the info.

[xming]

HP z400 has microcode 1D, apparently some (random) people uses it. I had a look
- d/l from HP http://ftp.hp.com/pub/softpaq/sp75501-76000/sp75720.tgz, extract the bios file
- use https://github.com/platomav/MCExtractor to extract the the microcode

[xming]

HP has released new BIOS, which contains the latest microcode for Westmere

[bunder]

x5650 is westmere ep, and according to intel 1e is indeed the latest revision for that processor. meanwhile bloomfield doesn't get diddly. rip my i7 920.

https://newsroom.intel.com/wp-content/uploads/sites/11/2018/04/microcode-update-guidance.pdf
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[xming]