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New HyperThreading Flaw Affects Intel 6th And 7th Generation Skylake and Kaby Lake-Based Processors (hothardware.com)
MojoKid writes: A new flaw has been discovered that impacts Intel 6th and 7th Generation Skylake and Kaby Lake-based processors that support HyperThreading. The issue affects all OS types and is detailed by Intel errata documentation and points out that under complex micro-architectural conditions, short loops of less than 64 instructions that use AH, BH, CH or DH registers, as well as their corresponding wider register (e.g. RAX, EAX or AX for AH), may cause unpredictable system behavior, including crashes and potential data loss. The OCaml toolchain community first began investigating processors with these malfunctions back in January and found reports stemming back to at least the first half of 2016.
The OCaml team was able pinpoint the issue to Skylake's HyperThreading implementation and notified Intel. While Intel reportedly did not respond directly, it has issued some microcode fixes since then. That's not the end of the story, however, as the microcode fixes need to be implemented into BIOS/UEFI updates as well and it is not clear at this time if all major vendors have included these changes in their latest revisions.
The OCaml team was able pinpoint the issue to Skylake's HyperThreading implementation and notified Intel. While Intel reportedly did not respond directly, it has issued some microcode fixes since then. That's not the end of the story, however, as the microcode fixes need to be implemented into BIOS/UEFI updates as well and it is not clear at this time if all major vendors have included these changes in their latest revisions.
.. doesn't mean what the article writer appears to think it means.
Anyhow, that a new highly complex processor contains subtle bug that's fixable without hardware modification isn't exactly earth-shaking news, surely? How about they just fix it, and we move on.
Mantis entry https://caml.inria.fr/mantis/v...
Spec update https://www3.intel.com/content...
From the mantis page: OCaml toolkit users noted that compilation was failing on skylake processors, when multiple concurrent processes were running. Additional testing found that test systems were producing incorrect results when running compiled code on skylake systems with HT enabled.
AMD Ryzen also seems to have a similar bug, related to hyperthreading that happens only in very special circumstances.
Quite a few Ryzen users have experienced instability problems during heavy compilation loads under Linux, especially those using compile-based distros such as Gentoo, but also under the Ubuntu subsystem on Windows.
There has been some debate whether the problems would have been caused by an actual bug, or if the people who experienced them simply had an unstable overclock - the latter being something that has also cropped up in forums recently.
Matthew Dillon, of Dragonfly BSD fame (and Amiga fame before that...) does believe that he has found a reproducible bug. He sent a test case about it to AMD in April.
This is not the first time Dillon has found a hardware bug in a AMD CPU. He found one for an earlier AMD CPU back in 2012 which was fixed in a microcode update.
I expect this to be fixed in a BIOS/microcode update soon, if not already in AGESA 1.0.0.6 - but I have yet to see any confirmation that it would have been fixed.
"We mustn't be caught by surprise by our own advancing technology" -- Aldous Huxley
The linked FA does not contain a link to the original Intel DOC:
https://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/6th-gen-x-series-spec-update.pdf
Unfortunately it does not contains much info...
You can often not simply install an update as a user. There is no way to do so without the BIOS vendor doing it for you.
All you losers with your over-priced Intel crap.
I've used nothing but AMD for 20 years and I have absolutely no probl%#^$^%J NJasllodofufm DUDFUF&&()()FDJJDNDMS .......
where's BATMAN now?
This makes the FDIV thing look like a walk in Central Park. Groves would roll in his grave if he could.
You can often not simply install an update as a user. There is no way to do so without the BIOS vendor doing it for you.
WTF does 'often' mean?
Either you can, or you can't. And in this case you can.
It would have taken you about 5 second to Google Intel microcode update...
> That's not the end of the story, however, as the microcode fixes need to be implemented into BIOS/UEFI updates as well and it is not clear at this time if all major vendors have included these changes in their latest revisions.
It _is_ helpful for the early-boot software to update the CPU's microcode, but it's not usually necessary. Linux has an on-the-fly CPU microcode updater. I would be shocked if Windows and OS X didn't have the same functionality.
I mean, think about the overwhelmingly common case where you're using an affected CPU on a motherboard that's no longer maintained by the vendor! Are you fucked until you go out and buy new mobos for every machine in your fleet? Lolno.
Oh wait. I fell for the clickbait. Silly me.
AMD: The Quality Goes In Before the Name Goes On.
Are you complaining about the topic as being too insignificant to deserve an article (as in: no need to tell people that they way want to update their servers) or are you preemptively commenting that other readers shouldn’t bother to comment on such an insignificant topic?
Either you can, or you can't.
Yep sometimes you can, sometimes you can't.
You seem to see how this works, but somehow you just dont know what that means.
Give queazocotal a break... It's not like there have been hundreds of stories about this on Slashdot in the last 10 years... Packed full of comments from people who know how to update microcode.
Yep sometimes you can, sometimes you can't.
You seem to see how this works, but somehow you just dont know what that means.
Give it a rest...
You 100% can.
End of story.
Wow! I kept reading over and over trying to find how it was escalating ring level or information leak through cache etc. but couldn't find it! I reaaaaallly wasn't expecting any type of "flaw" on slashdot to not be about some dumb security mistake. Way to surprise me again, SLUSHBOT
Give it a rest...
You 100% can.
No, you can't:
https://lists.debian.org/debia...
So the issue is not fixable in certain CPUs without disabling HT.
Stop it. Stop it now people!
Don't hurt MojoKid's feelings. It's not his fault that he doesn't understand how simple stuff like this works.
Give it a rest...
You 100% can.
No, you can't:
https://lists.debian.org/debia...
So the issue is not fixable in certain CPUs without disabling HT.
So you acknowledge that this is fixed, that anyone can apply the fix, but your only complaint is that the update isn't 'free as in liberty'?
You won't be happy until they open source the CPU??
Notice how Ubuntu, Microsoft, Apple, etc have taken the update?
Jesus fucking Christ. What has happened to Slashdot?
So you acknowledge that this is fixed, that anyone can apply the fix, but your only complaint is that the update isn't 'free as in liberty'?
No, read my post again. For certain models, the microcode fix is useless. You have to neuter your CPU by disabling hyper-threading. So money spent getting this expensive tech has gone down the drain.
Jesus fucking Christ. What has happened to Slashdot?
Apparently, many readers suffer from reading comprehension problems.
It will be a cold day in hell before I buy another Intel CPU, let alone let them install microcode on my current CPU.
Seven puppies were harmed during the making of this post.
It's a bit paradoxical that it was the OCaml team who found this bug, whereas OCaml is notoriously bad at parallelism.
The goal of this report is to make the existence of Intel CPU backdoors a common knowledge and provide information on backdoor removal.
What we know about Intel CPU backdoors so far:
TL;DR version
Your Intel CPU and Chipset is running a backdoor as we speak.
The backdoor hardware is inside the CPU/Bridge and the backdoor firmware (Intel Management Engine) is in the chipset flash memory.
30C3 Intel ME live hack:
[Video] 30C3: Persistent, Stealthy, Remote-controlled Dedicated Hardware Malware
@21:43, keystrokes leaked from Intel ME above the OS, wireshark failed to detect packets.
[Quotes] Vortrag:
"the ME provides a perfect environment for undetectable sensitive data leakage on behalf of the attacker".
"We can permanently monitor the keyboard buffer on both operating system targets."
Backdoor removal:
The backdoor firmware can be removed by following this guide using the me_cleaner script.
Removal requires a Raspberry Pi (with GPIO pins) and a SOIC clip.
Decoding Intel backdoors:
The situation is out of control and the Libreboot/Coreboot community is looking for BIOS/Firmware experts to help with the Intel ME decoding effort.
If you are skilled in these areas, download Intel ME firmwares from this collection and have a go at them, beware Intel is using a lot of counter measures to prevent their backdoors from being decoded (explained below).
Useful links:
The Intel ME subsystem can take over your machine, can't be audited
REcon 2014 - Intel Management Engine Secrets
Untrusting the CPU (33c3)
Towards (reasonably) trustworthy x86 laptops
30C3 To Protect And Infect - The militarization of the Internet
30c3: To Protect And Infect Part 2 - Mass Surveillance Tools & Software
1. Introduction, what is Intel ME
Short version, from Intel staff:
Re: What Intel CPUs lack Intel ME secondary processor?
Amy_Intel Feb 8, 2016 9:27 AM
The Management Engine (ME) is an isolated and protected coprocessor, embedded as a non-optional part in all current Intel chipsets, I even checked with the engineering department and they confirmed it.
Long version:
ME: Management Engine
The Intel Management Engine (ME) is a separate computing environment physically located in the MCH chip or PCH chip replacing ICH.
The ME consists of an individual processor core, code and data caches, a timer, and a secure internal bus to which additional devices are connected, including a cryptography engine, internal ROM and RAM, memory controllers, and a direct memory access (DMA) engine to access the host operating system's memory as well as to reserve a region of protected external memory to supplement the ME's limited internal RAM. The ME also has network access with its own MAC address through the Intel Gigabit Ethernet Controller integrated in the southbridge (ICH or
The goal of this report is to make the existence of Intel CPU backdoors a common knowledge and provide information on backdoor removal.
What we know about Intel CPU backdoors so far:
TL;DR version
Your Intel CPU and Chipset is running a backdoor as we speak.
The backdoor hardware is inside the CPU/Bridge and the backdoor firmware (Intel Management Engine) is in the chipset flash memory.
30C3 Intel ME live hack:
[Video] 30C3: Persistent, Stealthy, Remote-controlled Dedicated Hardware Malware
@21:43, keystrokes leaked from Intel ME above the OS, wireshark failed to detect packets.
[Quotes] Vortrag:
"the ME provides a perfect environment for undetectable sensitive data leakage on behalf of the attacker".
"We can permanently monitor the keyboard buffer on both operating system targets."
Backdoor removal:
The backdoor firmware can be removed by following this guide using the me_cleaner script.
Removal requires a Raspberry Pi (with GPIO pins) and a SOIC clip.
Decoding Intel backdoors:
The situation is out of control and the Libreboot/Coreboot community is looking for BIOS/Firmware experts to help with the Intel ME decoding effort.
If you are skilled in these areas, download Intel ME firmwares from this collection and have a go at them, beware Intel is using a lot of counter measures to prevent their backdoors from being decoded (explained below).
Useful links:
The Intel ME subsystem can take over your machine, can't be audited
REcon 2014 - Intel Management Engine Secrets
Untrusting the CPU (33c3)
Towards (reasonably) trustworthy x86 laptops
30C3 To Protect And Infect - The militarization of the Internet
30c3: To Protect And Infect Part 2 - Mass Surveillance Tools & Software
1. Introduction, what is Intel ME
Short version, from Intel staff:
Re: What Intel CPUs lack Intel ME secondary processor?
Amy_Intel Feb 8, 2016 9:27 AM
The Management Engine (ME) is an isolated and protected coprocessor, embedded as a non-optional part in all current Intel chipsets, I even checked with the engineering department and they confirmed it.
Long version:
ME: Management Engine
The Intel Management Engine (ME) is a separate computing environment physically located in the MCH chip or PCH chip replacing ICH.
The ME consists of an individual processor core, code and data caches, a timer, and a secure internal bus to which additional devices are connected, including a cryptography engine, internal ROM and RAM, memory controllers, and a direct memory access (DMA) engine to access the host operating system's memory as well as to reserve a region of protected external memory to supplement the ME's limited internal RAM. The ME also has network access with its own MAC address through the Intel Gigabit Ethernet Controller integrated in the southbridge (ICH or
There are a lot of inaccurate comments here. First of all, reloading a new BIOS/system firmware may be the best solution for most users, however it is not the only solution. If you know how you can do a hotfix load of firmware in Linux and I suspect other OSes.
For example, I downloaded the latest firmware from Intel (dated 10 May) and placed it in /lib/firmware. Then running:
echo 1 > /sys/devices/system/cpu/microcode/reload
was enough. In the log is an entry:
[2246029.695843] microcode: updated to revision 0xba, date = 2017-04-09
In addition, the article points to a message on the debian-devel (not users) mailing list. This indicates that i3/5/7 processors with hyperthreading are affected. AFAIK, no i5 processors have hyperthreading, even though the family/model/stepping on my system is indicated in the message as vulnerable.
CPU(s): 4
On-line CPU(s) list: 0-3
Thread(s) per core: 1
Core(s) per socket: 4
Socket(s): 1
Well what is it? Hyperthreading or all skylake/kaby lake? Curious minds want to know.
One last thing. The current firmware package is dated May 10. Seven weeks ago, The firmware itself was produced April 9 -- 11 weeks ago. Unless Intel has not updated yet for this, many posters here are running around with their hair on fire about something already fixed.
But I guess that is normal for slashdot.
There needs to be serious penalties for companies that create poor products with serious defects. These flawed processors certainly qualify as inferior products.
You work for AMD, right? :D
No, read my post again. For certain models, the microcode fix is useless. You have to neuter your CPU by disabling hyper-threading. So money spent getting this expensive tech has gone down the drain
I can read your post until I turn blue, but it won't change the fact that you are wrong.
All models have microcode updates, that don't affect hyoerthreading at all.
Please hand in your geek credentials.
different AC, but regardless you are wrong he is right. all of the CPU's can be fixed/updated via microcode, however for some models that haven't had publicly available fixes published you have to go to your vendor and ask them for it. that doesn't mean it requires them to do it, but they are the only ones that will currently have the updates.
You obviously have no idea how difficult it is to test all features of a complex CPU with all data patterns and all instruction sequences under all conditions. Product releases would be delayed for years.
Contribute to civilization: ari.aynrand.org/donate
Core2 quad core w/8G still works well. Missing a few nice things on the motherboard like USB3 and SATA3, but it's good enough for what I use it for now. And afaik it's pre-ME; at least, the tool for finding it doesn't. Yes, a primitive one could be and probably is hidden, but not the one causing all the problems now. Security by obsurity, plus Luddite, wins again?
you forgot .kajsdfl^Y&%k(*ajs)&*f CARRIER LOST
Oh fuck off, Intel make billions, they should be able to test it properly if the hackers that hack it can find these flaws.
At the very minimum they could put a bounty out!
YOU obviously have no idea how to do anything but make excuses for sloppy work.
Every time a new flaw is found, be it Windows or Linux kernel, it's always 64-bit versions of stuff. It's probably because of better GPU processing. Hackers use a person's GPU for less footprint and speed. It also wouldn't surprise me if intelligence agencies have given up on keeping up with 32-bit exploits as well since no one uses it anymore.
I only allow 80, 8080 & 443 in/out here
Awww, how cute.
Did it occur to you that if a hacker is able to modify the IME system, that he can direct the packets to use port numbers other than 16992-16995? 443 would be my goto port.
There is no America. There is no democracy. There is only IBM and AT&T and DuPont, Dow, General Electric, and Exxon
...NO CARRIER ?
All models have microcode updates, that don't affect hyoerthreading at all.
[Citation needed]
Please hand in your geek credentials.
Unless you have proof all Skylake Kaby Lake CPUs have microcode updates that fix the issue without disabling HT, you'll have to hand in yours.
I never made it to chapter two. Every focus was on controlling message and image. No acknowledgement this directly affected customers, no outreach, no mitigations. Much anger at people communicating a flaw in the product, and defying Intel's response plan and schedule.
Seeing these reports of the response doesn't fix my impression.
It's a quantum update, you do it and not do at the same time.
Yet AMD don't seem to have a problem, despite having far less resources to play with than Intel.
Putting aside the conspiracy theories for just a moment...it is the case that these things are hard to test.
Back in the days of the VAX, when Digital had the largest private network in the world (DECnet based), the validation for the FPU included a distributed computing effort called AXE which distributed random bits of FPU code to VAX systems all round the world trying to catch errors in the logic. I have no doubt the problem is exponentially harder now...
This could be automated. And with ai advances, a human wouldnt need to write the automation at all.
Untrue. VME was broken on Ryzen at launch. Fixed with a microcode update.
for future intel chips, the microcode is expanding in size at a rapid rate as Intel adds more advanced ISA features, that's now the primary focus since there is not much to be gained from physical improvements.
See subject: AMT/Intel Mgt. Engine uses ports 16992-16995 & I only allow 80, 8080 & 443 in/out here on a SINGLE stand-alone system - you must also be CERTAIN your router's internal ware is "solid" as well (turn off things like UPnP etc. & HAS NO KNOWN BACKDOOR EXPLOITS (tons do unfortunately) - get it patched ASAP if it's KNOWN exploited & TONS of routers, ARE https://it.slashdot.org/comments.pl?sid=9995967&cid=53488785/
* GOOD ROUTERS/MODEMS HAVE PORT FILTERING OPTIONS (crappy ones do not) - No "raspberry PI" needed plus once you disable the AMT engine in software? They can't even produce a malware to 'repatch' this (bios updaters require it in usermode ware, e.g. ASUS).
APK
P.S.=> Good luck - as it's the BEST EASIEST DEFENSE using what you already have (hopefully, again as not ALL modems have port filtering but most do & certainly GOOD ONES DO) vs. this threat by stopping it being able to communicate in/out period, outside of the INTEL chipset, & stopped external to it via a router/firewall hardware... apk
I thought you only let elephant cock in to you gaping asshole but you you tell me that you let any diseased connection in
Does this one get a nifty name?
There is no XUL, only WebExtensions...
Hey retard you posted this multiple times already.
slashdot_commentator: Hilarious to see you pwned by APK constantly https://hardware.slashdot.org/comments.pl?sid=10785103&cid=54692565/ suddenly refusing to use your /. registeredluser account which you brag on and yet you post unidentifiably anonymously. Has self-righteous registered wannabe Christ in yourself turned to Satan? Yes. Hahahahaha. So much for the superiority of registered losers like you. He thought of a valid protection. You haven't.
See subject: AMT/Intel Mgt. Engine uses ports 16992-16995 so filter those ports in a router external to OS/PC.
No "raspberry PI" needed plus once you disable the AMT engine in software? They can't even produce a malware to 'repatch' this (bios updaters require it in usermode ware, e.g. ASUS).
(I only allow 80, 8080 & 443 in/out here on a SINGLE stand-alone system (no home LAN but TCP/IP connected online))
HOWEVER - Be CERTAIN your router's internal ware is "solid" as well (turn off things like UPnP etc. & HAS NO KNOWN BACKDOOR EXPLOITS (tons do unfortunately) - get it patched ASAP if it's KNOWN exploited & TONS of routers, ARE https://it.slashdot.org/comments.pl?sid=9995967&cid=53488785/
* GOOD ROUTERS/MODEMS HAVE PORT FILTERING OPTIONS (crappy ones do not) !
APK
P.S.=> Good luck - it's the BEST EASIEST DEFENSE using what you already have (hopefully, again as not ALL modems have port filtering but most do & certainly GOOD ONES DO) vs. this threat by stopping it being able to communicate in/out period, outside of the INTEL chipset, & stopped external to it via a router/firewall hardware... apk
See subject: Cat got your tongue?? As AMT's software interface = gone (ez) IT CAN'T UPDATE BIOS TO 'flash' it!
* THIS PROTECTS vs. IT, No "raspberry PI" required no questions asked.
(What's the MATTER blowhard bullshitter bigmouth? POSTING UNIDENTIFIABLE AC NOW?? Why not use your FAKE NAME for your FAKE LIFE "registered 'luser'" ACCOUNT NOW??? LOL!)
APK
P.S.=> See, a STUPID BIGMOUTH FAKE NAME FUCK LIKE YOU is NEVER, ever going to get the best of me - you're too stupid! You like calling others that as well as picking on AC posters (who are MORE HONEST THAN A FAKE NAME "ne'er-do-well" DO NOTHING ZERO FUCK LIKE YOU & you know it, loser)
Hahahaha- I went thru your post history & based on your BIG MOUTH I can easily tear you to SHREDS, using YOUR OWN BLOWHARD do nothing/no proof of your BIG TALK bullshit AGAINST YOU -
Say 1 thing - go for it - I'll PUBLICLY HUMILIATE YOU & I take GREAT PLEASURE in CRUSHING big mouth do nothing ALL TALK STOOGES like you (ala Cardinal Richelieu style)... apk
Very funny
So?
If you really believe that... Oh boy, would you like to invest in some prime real estate? It's just past this bridge...
Did it occur to you it's in hardware? How are they going to alter that as AMT's software interface = gone (ez) & IF so, provide me proof of it - ok fuckwad?? Good luck! It's unpatchable in USERMODE then so no malware can do it! E.G. ASUS bios update won't work minus Intel Mgt. Engine!
* SEE SUBJECT & YOUR POOR ATTEMPT @ HIDING YOUR FAIL 2x via bogus downmods in the links below of this post you pitiful BLOWHARD FAKE NAME USING FUCK https://hardware.slashdot.org/comments.pl?sid=10785103&cid=54690141/ & https://hardware.slashdot.org/comments.pl?sid=10785103&cid=54690965/
APK
P.S.=> No, shithead - I won't ALLOW you to play those games - & yes WE ALL KNOW it's YOU DOING IT, seeing as you WON'T USE YOUR "registered 'luser'" ACCOUNT NOW (lol, though you "RAVE" on HOW MUCH 'better' YOU ARE FOR IT, you DELUDED little fake name for your FAKE DO-NOTHING ZERO LIFE, motherfucker)... apk
See subject: AMT's software interface is gone (ez) malware can't flash bios.
* THIS PROTECTS vs. IT, No "raspberry PI" required... no questions asked.
I SEE YOU TRIED DOWNMOD HIDING THIS POST TOO as it proves you WRONG as you have others like it https://hardware.slashdot.org/comments.pl?sid=10785103&cid=54690851/ - yes, we KNOW it's you & yes that's pitiful!
APK
P.S.=> What's the MATTER blowhard bullshitter bigmouth? POSTING UNIDENTIFIABLE AC NOW?? Why not use your FAKE NAME for your FAKE LIFE "registered 'luser'" ACCOUNT NOW??? LOL! See, a STUPID BIGMOUTH FAKE NAME FUCK LIKE YOU is NEVER, ever going to get the best of me - you're too stupid! You like calling others that as well as picking on AC posters (who are MORE HONEST THAN A FAKE NAME "ne'er-do-well" DO NOTHING ZERO FUCK LIKE YOU & you know it, loser)... apk