Sky/Kaby lake Intel hyperthreading bug

Was wondering too.

For completeness, always nice to mention the source:

lists.debian.org/.../msg00308.html

Some discussion:

www.phoronix.com/scan.php

On my 9350, the perl script written by Uwe Kleine-König reports "Your CPU is affected, but your microcode is new enough"... dmesg shows:

...

[  279.241217] microcode: sig=0x406e3, pf=0x80, revision=0x9e

[  279.242197] microcode: updated to revision 0xba, date = 2017-04-09

[  279.243096] microcode: sig=0x406e3, pf=0x80, revision=0xba

...

So, it appears that BIOS 1.4.17 includes microcode rev 0x9e, which does not include the fix. Microcode rev 0xba is packaged with Fedora, which is new enough (at least according to the perl script).

Updated my system Zesty 17.04 to use the intel microcode package for 17.10 which is the latest put out by intel (The dependencies are met just fine in Zesty, and don't think it will cause any issues), but my reported microcode didn't change.  Still says 0x4e, so I'm guessing there is a need for a BIOS/UEFI update.  In reading it sounded as if the microcode package may only fix certain models like skylake :(

Not necessaIrily. You do not mention your OS. On Linux, the OS can load new microcode on bootup, and it may be that that is being reported, rather than anything in the bios.

@Community,

I can confirm that Dell engineering is working on a hyperthreading fix for the 9350/9360, as well as other models, in the form of BIOS updates. Those BIOS updates should be coming out in the near future.

I'll get back with updates when I know more.

Software Updater just updated the microcode to 3.20170511.1 (Ubuntu 17.04) on my 9360.

However, the fix to the hyperthreading issue appears to be in launchpad.net/.../3.20170707.1 which is only released for Artful. Hopefully a Zesty release will follow soon.

Any word on the BIOS update for the Dell XPS 9360? Online it still shows 1.3.5 as the latest version released May 12. I noticed most other manufactures, including Acer has released BIOS updates for all their major laptop models. Most articals online says manufactures had access to the microcode update back in April.

For Linux. microcode-20170707 has just come out which is supposed to handle the all the Skylake (9350) and Kabylake (9360)  processors for this bug. I know Debian has it, Redhat, probably Ubuntu. You need to make a new initrd so that the microcode gets loaded at boot.

@DELL-Justin C

I noticed a BIOS update for the Dell XPS 9360 (Bios 1.3.7). It doesn't say anything about the hyperthreading microcode update, all it says is "Fixes & Enhancements: Enhance Windows 10 Enterprise Redstone 2 support"

Do you know if this BIOS update includes the fixes relased by Intel?

www.dell.com/.../driversdetails

Hi Codster,

According to my contact with Dell engineering, yes, 1.3.7 is the version with improvements that affect hyper-threading. I'm trying to get more documentation on the matter and will get back.

bios update 1.4.18 for 9350 is here www.dell.com/.../driversdetails

Did you get any more information on 1.3.7 @DELL-Justin C? Thanks

Hi Basteed,

I will grab a 9360 Dev edition from the lab and see if I have the same boot order issue as you did. I'll get back.