Skylake / Kaby Lake Hyper-threading bug

Thanks for the write up, but you could have begun and ended with your Step 6:

[6-]
Go to this link ---> Click Here to get an idea or learn how to upgrade your CPU Microcode to the lastest version. It is detailed enough there.

Your "Click Here" links to @Dufus 's post on how to use VMware's CPU Microcode Update Driver, which he links to at the top of his post.

"So thanks to VWware for providing an elegant solution and signed driver..."

VMWARE CPU MICROCODE UPDATE DRIVER
https://labs.vmware.com/flings/vmware-cpu-microcode-update-driver

"This Fling is a Windows driver that can be used to update the microcode on a computer system’s central processor(s) (“CPU”). This type of update is most commonly performed by a system’s firmware (“BIOS”). However, if a newer BIOS cannot be obtained from a system vendor then this driver can be a potential substitute.

Features

The driver can update the firmware on Intel or AMD CPUs. The driver attempts to update the processor when the driver is started, when the system is booted, or when the system resumed from a low power state (e.g., hibernation).

The driver will report its actions in the OS’s event log that can be examined using “Event Viewer”. The driver reports whether it found supported processors and if an update was attempted or successfully performed on a processor. This information lets the user know whether the driver is providing a benefit (otherwise they can uninstall it). For example, the processors might already have the latest firmware version."

@Dufus's post is linked in Post #2 here, and maybe @Assembler can add something to his Post #1 pointing to solutions for Windows and Linux so new readers can find them right away instead of reading through the whole thread, or searching for other threads

 

@Papusan and @Mr. Fox :Will test Wprime long and short test on high performance plan and Defender AV turned off. Or should I turn on AV and switch power plan to Balanced for realistic test?
Update: CB r15 score is back to intended score of 684, it seems lesser the ambient temps more turbo boost though its more strict now.
I will return after battery of tests; Anybody need the compressed version of VMware uCode updater along with intel and AMD uCodes?

 

Glad it's back to what it should be. I only use High performance power plan and never set any offset for AVX extensions. I do not use any antivirus software. So, do whatever is a realistic test for you.

 

You should compare with your best scores. Aka run tests in the same way!!

 

@Mr. Fox @Papusan @hmscott :
I've basic results, Wprime long and short, Cinebench r15. There were lot of background apps like web browser, some files transfers, AV and power plan was set to Balanced.

 

Thanks for the tips When I find time I will edit my guide depending to your suggestions or you can do it what you can see best you can edit my post if you want

 

If anyone has PC with EOL status or vendors taking a lot of time in shipping BIOS update to you, use this zip file and extract it and run install.bat with admin privileges and if you didn't like it simply run uninstall.bat to remove the uCode update.
@Mr. Fox @hmscott @Papusan @rinneh @iunlock @Mobius 1 I'm attaching the file containing all intel and AMD uCodes.
EDIT: Forgot to give password. Thanks @hmscott. +Rep
Password: ucode

 

When it comes to supporting large numbers of people for a problem like this it comes down to being as simple and straightforward as possible.

Too many steps, too technical of an interaction to make it work right, and most normal people will wait for an easier method.

Download, unpack, install with feedback, done.

No reading registries, no special skills, no decisions needed.

@Vasudev has the right idea.

I hope it works right for the people that need it, and please give him feedback if it does't... and to say thanks if it does work

 

Seems like I took the hard way here then thats why I said only [Advanced or intermediate PC user can do it] on my guide... but the one that @Vasudev did are much simpler & easier but... there is one note about that... not all skylake CPU will benefit from this Update Microcode CPU Fix... because only skylake cpu which contain those codes that I mentioned on my guide which is [0x406E3] or [0x506E3] will benefit from it

Reference :- Please read on this link https://lists.debian.org/debian-devel/2017/06/msg00308.html and you will know what I am talking about

 

VMware's CPU Microcode Update Driver takes care of checking to see if the CPU needs the update, and only applies if needed. And, it then puts in a log entry into the System Event Log to inform the user of what it did.

That would seem to be enough?

You could go through the efforts to check ahead of time to see if you need it, but as far as I can tell most BIOS / CPU microcode levels on most computers are going to be a bit behind in updates.

It's easier to just take those simple steps to download, unpack, install with feedback, and check the logs to see what happened.

 

I used the Dufus method to update my microcode right now:
http://forum.notebookreview.com/threads/how-to-update-microcode-from-windows.787152/#post-10553860

So, microcode now reads "BA" in HWInfo, so it's sucessfully updated, and also says so in Event Viewer. If MSI release an updated BIOS that includes the latest microcode I'll probably uninstall the driver, and use the updated BIOS instead, seems like a cleaner & more permanent solution than a driver loading at each boot.

I got the highest score I've seen in Cinebench since updating to latest microcode: 1048 points, just 7 more than my previous highest, ran it twice & got 1048 both times. Not particularly scientific though, and I somewhat doubt the latest microcode can make such differences.

 

Well, if we broaden our thoughts about "BIOS" and "microcode" a bit, maybe keeping the driver isn't such a bad idea...

The BIOS usually comes with some other changes than just microcode updates. I've found Asus and MSI both seem to "detune" their BIOS's gradually over time, it varies from notebook to notebook.

There are plenty of times over the years I've regressed from a BIOS update that reduced my maximum multiplier for CPU core OC'ing, had maximum power levels dropped, or performance was just inexplicably reduced.

The ability to update microcode from the OS free's us from the motherboard vendor's update cycle, and other "extra's" they put into the BIOS.

Intel seems to make microcode changes for quite a while after CPU release, so it could come in handy as a way to get around vendors that have stopped supporting BIOS updates.

Just a thought

 

It's good to have the flexibility no doubt so you have the choice, it's a good thing.

 

Is there a reason you have a password on this file?
How are we supposed to extract it if it's password protected?

 

@Vasudev

 

Yes indeed you're correct. Anyway, it will update the microcode only with the latest version on Linux, dunno about Windows; it could be too complex. Generally, CPU microcode is a quick fix to correct CPU bugs which cannot be shipped as firmware but simply a instruction written to overcome or avoid the errata at least.

 

I feel stupid about it. Thanks for pointing it out. I forget things here and there. Thanks.

 

Hey, it happens to everyone from time to time, that's what user alpha testing is all about

 

I know that , you are right what I meant was the new microcode update will only fix HT bug for only specific skylake that contains either those codes which is [0x406E3] or [0x506E3] if it is other than that (even if it is a skylake cpu) then this update will be useless and it won't fix those bugs at all , that is why my guide is important for those users , it may not be simple but... worth it

So what I am saying is... you must check your skylake cpu if having this code or not... because if it is not...then update your microcode is useless

 

My guide was talking for MS Windows OS users... I never mentioned updating using linux , CPU Microcode is not specific to a certain OS... once the Microcode is updated .. it will be used to all OS no matter if it is [Windows,Linux, even Mac!]

and my words have a proof for this

If you looked at the image on the attachment that i have uploaded... the key on [Previous Update Revision]---> which means default original microcode version (from BIOS) is the same as [Update Revision] so.... that means that the microcode doesn't update within the specific OS but it updates it... internally...inside the CPU

Which means even if I reformatted my Laptop and installed completely a new OS... it will have the same updated microcode versions that I have installed previously

 

Thank you

 

Quite right. I applied the patch on linux and found that revision was same as the one that is affected by HT bug. It is just like @Mr. Fox said, linux applies any uCode or FW upon boot and not installed globally like Windows does.
If you patch it in windows, its persistent until your PC reaches the end of the lifecycle.

 

Did not work as well as it should have? I thought the microcode update was permanent if done through Windows?

I own a laptop equipped with an i7 6700 skylake desktop socketed processor (Eurocom Tornado f5). I updated my cpu with the method linked by the THEBOSS619 and successfully went from revision A6 to BA through windows (checked with HWINFO64).
However my bios still indicates revision A6?

Sorry if I am a newb and did not understand correctly what was said.

 

I think you're right. I've also updated my microcode to BA using the Windows method, and each time the PC boots the driver loads the CPU with the updated microcode - you can see it in Event Logs in Windows Logs>System> cpumcupdate states "Sucessfully updated microcode on one or more CPUs" - this event log happens at each boot showing that the driver loads the new microcode at each boot. I also checked in my BIOS and my BIOS states version A6 still, so it's only at Windows boot that the new microcode is applied each time. If your vendor ever releases a new BIOS to fix the issue, then I'm guessing it'll say microcode version BA in that new BIOS, and then you can uninstall the cpumcupdate driver as it will no longer be needed - this is my understanding of whole this thing works.

 

Then I wonder if as he said the permanent update works on some computer and not on other?
It's strange anyway because the software clearly states that is an in OS update that does not replace a BIOS update and therefore not permanent. I had hoped there was some kind of computer magic at work here lol.

 

Yeah, when I read that post I thought it was strange too, as I don't see why the driver would say it's loaded the new CPU microcode at each boot otherwise. I suppose it doesn't matter much, keep the current way of updating the microcode automatically at each boot or update the BIOS when it eventually comes through, both seem fine.

 

I've been researching this bug, the conditions upon which this will happen are extremely rare, and most 32/64 bit code wouldn't even cause these errors. My guess is the Debian guys were regression testing some legacy code when they found this. I mean first you have to use the "H" registers and the wide registers, and on top of that less than 64 bit instructions and short 8-bit register access. I don't think any of us are going to run across this problem.

 

In essence even the BIOS is "reloading" the microcode patches every power on, doing it from the OS is just another "temporary" patch that goes away when the OS is restarted.

The CPU is a fixed immalleable constant, you can't change it's behavior except through the overlay of microcode updates.

AFAIK, Windows doesn't have a mechanism to update the microcode built in that is user accessible, which seems kinda weird when you think about it, so we have VMware to thank for their contribution.

Also, whether or not newly discovered errata play a role in your day to day use of Windows, Linux, etc it's always a good idea to understand how to update just in case something is discovered that turns out to be a critical bug.

Whether or not normal operation causes the errata to be a problem, some malware might take advantage of errata - so it's good to know how to patch microcode.

Let's be thankful this bug isn't the one that takes out the internet

 

I thought vasudev said the microcode is written permanently onto the chip after you run the update?
(e.g. if you reformat the OS, the new microcode is still there?)

 

Not in my experience as well as others just a few post above and the tool states it's an in OS patch so it does not retain the update after a reformat. The bios is still using/showing the old microcode revision it's just the OS that loads the new one.
IDK why THEBOSS619 and Vasudev said it's permanent when patching in Windows but maybe it works permanently for them?

 

I didn't say it was permanent, @THEBOSS619 said he was affirmative that even clean install windows wouldn't erase the uCode.
Maybe @Prema can help in these matters involving BIOS/EFI. I don't even have a clue about it.
Well, even Intel docs, I believe says just use microcode.dat file to update the uCode and everything is okay. They didn't mention if its semi-persistent or persistent throughout the machine's lifecycle.

 

oh ok I get it now. It was intel (phraseology? sorry not native speaker) that was confusing. They should have said it better and update their docs then .

 

Exactly!! New bios upgrade for notebooks can mean opportunities to cripple other features. All the ODM's love to screw up other things like eg fan profiles etc. + more crippled power settings with every update. Damn the poor soul who is the Guinea Pig. In worst cases you risk yooo can't downgrade to previous version. It's a lottery!! A dangerous one.

 

Sorry for replying late & Sorry if I couldn't be clear for that my fault but it will be permanent for only those who got the codes that I mentioned on my guide I will update my guide once I get back home(I'm on vacation with my family). Here is another proof from another site saying that when checking through registry---> https://superuser.com/questions/355691/how-do-i-see-cpu-microcode-version

Unless I'm wrong & my CPU magically connected to internet & updated my cpu microcode

But I can assure you that & I even did a clean format windows on my laptop to test it. And it is the same BA version of microcode CPU.

About showing an event that the Microcode is being updated on the event viewer... I don't have that at all..

If anyone of you have another way to check microcode cpu then please let me know because I'm starting to think that I'm the only one who did this permanent .

That's why when I said if you have different codes other than I mentioned on my guide then forget it because the update will be useless and I think (not sure) when you update your microcode while it is having different code that I mentioned on my guide then it will be loaded only for your current windows and it won't be permanent

 

It's not possible, so it isn't happening

IDK what you are seeing, or how it's happening, but the CPU can't be changed - microcode can't be downloaded to it.

From your own link:
https://superuser.com/questions/355691/how-do-i-see-cpu-microcode-version

"The Microcode is ephemeral, meaning every power down of the CPU it is reset and has to loaded again! So if you check in Linux, you get the Version included in your Linux Distribution (or the base version included in your BIOS/UEFI). This won't tell you what version Windows installs on boot! – Josef Jan 13 '15 at 14:52"

Here's some instructive text from the Debian Microcode Wiki:

Spoiler

"CPU Microcode

Processor microcode is akin to processor firmware. The kernel is able to update the processor's firmware without the need to update it via a BIOS update. A microcode update is kept in volatile memory, thus the BIOS/UEFI or kernel updates the microcode during every boot.

Processors from Intel and AMD may need updates to their microcode to operate correctly. These updates fix bugs/errata that can cause anything from incorrect processing, to code and data corruption, and system lockups.

It is very difficult to know for sure whether you need a microcode update or not, but it is not safe at all to just ignore them. You might not notice their effect and have precious data silently corrupted, or an important program silently misbehave.

Or you could experience one of those unexplainable and infrequent software issues (such as kernel oops, application segfaults) or hardware issues (including sudden reboots and hangs).

Releases of new microcode updates are more frequent on young processors, but the release of new microcode updates for older processors do happen.

The BIOS (or UEFI) updates the CPU microcode during boot, however most of the time either the motherboard vendor won't issue frequent BIOS/UEFI updates, or the user won't install such updates. For these reasons, the system processor is likely to be running with outdated microcode on a vast number of systems."...
https://wiki.debian.org/Microcode

When you figure it, please let us know

 

Please re read my post again because I edited it while you replied before modifying my post above

I will quote it here to avoid any confusion

You are absolutely right it makes sense .... let me try and check again on my laptop once I arrive home but I checked it multiple times really but no harm to check again .... I will let you know once I arrive home & finished checking

 

I now checked again... same results actually... I guess the only way to find out is to take a dump BIOS from my laptop directly and save it to the harddisk and see if my bios is having the latest microcode cpu through extracting the bios file as on the asus website when seeing the same version of BIOS that I have it says on the changlelog... [Bug fixes or optimizing preformance] without saying any further details.

If I saw a BA version [Which means same result] from my current BIOS ... then I must check the BIOS file from asus site and download it and compare it between my current BIOS and the one from asus site in that way.. it will end any confusion and the answer will be like [Yes or No] thing

I will provide screen shots to prove it

 

Better to uninstall the uCode first, then apply BIOS update.

 

Hi, can you update your windows tool to include the kaby lake microcode update? (the current file you uploaded has no microcode for kaby lake). The latest Asus Bios had a new microcode for Kaby lake, so one exists somewhere.

 

Your CPU model?

 

7820HK

 

This is the link I used:

See:
https://downloadcenter.intel.com/download/26798/Linux-Processor-Microcode-Data-File


I didn't even check to see if my processors were on that list... lol...

Is there another, more complete list, available?

 

Update to http://forum.notebookreview.com/thr...per-threading-bug.806317/page-3#post-10553584 - updated BIOS for Clevo chassis will be available in a couple of weeks

I can't speak for ASUS or MSI, but I haven't seen Clevo detune their BIOS and though there might be a couple of other entries in the changelogs, there's nothing like this ^^^^ included!!

 

That's great news with Clevo providing quick action

 

Don't worry, your vendor *will* ship the update to you. Anyway, have you tried running the Install.bat file and see it updates the uCode after restart? Even my CPU i7 6700HQ isn't listed. Haha

 

Yes i checked the event viewer. it said this cpu isn't supported, (or no microcode available, I forgot) no update done.

 

Moreover the uCode looks for specific signatures starting with 0x563 or something which is mentioned by @THEBOSS619
try linux and run a perl script provided by debian and if you see the message "Your CPu is affected" then contact your vendor.

 

As @ Vasudev said

Just to inform you guys I still didn't come back home due to my vacation (as I mentioned before) so still didn't do anything as I am now using a different pc [my friends pc]

So... I will keep you informed once I reached home with all the details & pictures
Sorry if it is taking time more than expected :/ but can't ignore vacation with my family

 

I have the CPU ID 0x506E3 so I followed the @Vasudev quick guide and run install.bat and restarted my computer...I checked the CPU ID again it's still 0x506E3...

 

Signature mustn't change whatsoever. See microcode update revision in hwinfo CPU or in summary screen.