back to article Kernel-memory-leaking Intel processor design flaw forces Linux, Windows redesign

A fundamental design flaw in Intel's processor chips has forced a significant redesign of the Linux and Windows kernels to defang the chip-level security bug. Programmers are scrambling to overhaul the open-source Linux kernel's virtual memory system. Meanwhile, Microsoft is expected to publicly introduce the necessary changes …

  1. Byron "Jito463"

    Re: Haven't done a full read through so don't if this has been raised...

    "I've been using AMD cpu's since the K series in the late 90's **** I feel old now

    Smug but old :)"

    I know what you mean. I've been using solely AMD since my 486 DX/2 66MHz CPU.

    What can I say, I like supporting the underdog.

  2. Flakk Silver badge

    Re: Haven't done a full read through so don't if this has been raised...

    >I've been using AMD cpu's since the K series in the late 90's

    As you're a long-time AMD fan, would you satisfy my curiosity? Was the increase in your electric bill through the use of Bulldozer-class CPUs offset by the ability to supplement your furnace with your computer during the winter?

  3. kain preacher Silver badge

    Re: Haven't done a full read through so don't if this has been raised...

    In my case yes. seriously My room was consistently 10 degrees warmer then the rest of the house. Toss in a descent video card and I had to use monster after market cpu cooler or the damn CPU would over heat and shut down.

  4. Queeg

    Re: Haven't done a full read through so don't if this has been raised...

    Hell yes, I've worked in some frigid little icebox cubicles in my time thanks to ferked up AC.

    My home office is always toasty. :)

  5. eldakka Silver badge

    > That would allow ring-3-level user code to read ring-0-level kernel data.

    What about reading ring level -3? Could this be used to access the IME?

  6. crashatau

    Can you hear that sound.....

    Can you hear that?

    That is the sound of AMD fanboys gloating gleefully. :)

  7. Anonymous Coward
    Anonymous Coward

    Re: Can you hear that sound.....

    It's kind of a soft, humming sound, possibly accompanied by the sound of a bucket of pop corn being reached for...

  8. mirage

    Excellent use of example

    “Think of it like god sitting in the clouds”

    While humans have been going into space since decades ago, god is still stuck in the clouds. Interesting, to say the very least.

  9. peterkin

    Re: Excellent use of example

    Magellanic clouds?

  10. Field Commander A9

    Ask for refund?

    The Complete Care package for my Alienware 15R2 (i7-6700HQ) expires on April 2018. Do you think I can ask Dell for a refund for my laptop for this reason?

  11. Jonathan Richards 1

    Re: Ask for refund?

    Oh, certainly you can ask. Don't expect a returns label to be issued before, say, April!

  12. JonHendry

    Is the Linux fix optimal?

    Just wondering, what are the chances that the Linux fix is the best possible? Perhaps Apple and/or Microsoft will come up with a faster solution, perhaps a better general solution which could be applied to Linux as well. Or, perhaps OS-specific fixes taking advantage of characteristics of Mach or Windows that Linux doesn't happen to have. (Not a slam on Linux, just noting that the OSes have different architectures and features that could conceivably come into play in designing a fix.)

  13. herman Silver badge

    Maybe enlisting the ME as a co-processor for I/O can speed the chips up again.

  14. Jamie Jones Silver badge


    Only a few months ago I bought a KabyLake - only my second intel purchase ever... ho hum

  15. Anonymous Coward
    Anonymous Coward

    VMS is calling

    There's a reason AMD didn't follow Intel down this hole. They've known about it for nearly 20 years and Intel did too and chose to implement anyway. Find an old copy of VMS Internals and Data structures. If VMS couldn't keep you out, it killed itself to limit the damage. "Page Fault IPL too High". Intel got the engineers but AMD got the IP when the lab/fabs were sold off. Evidently, AMD paid attention.

  16. Stoneshop Silver badge

    Re: VMS is calling

    Intel got the engineers but AMD got the IP when the lab/fabs were sold off. Evidently, AMD paid attention.

    The DEC engineers that ended up at Intel were, for a large part, from the software side of things; the compiler group went over almost lock, stock and barrel. AMD got a number of Silicon Wranglers who had been working on AXP and chipsets; several AMD processor subsystems bear a strong resemblance to their AXP counterparts.

  17. Flakk Silver badge

    Re: VMS is calling

    The idea of where an ancient bug rears its head depending largely on the migration destination of a bunch of DEC hardware veterans is positively fascinating.

  18. MasterfulShog

    Re: VMS is calling

    More than you know... I believe, without knowing, that early AMD64 and Alpha processors were designed to be pin compatible. Certainly if you looked at the motherboard for early AMD64 you would see an Alpha southbridge.

    I reckon there was a lot of IP sharing, and Jim Keller of course.

  19. Anonymous Coward
    Anonymous Coward

    Re: VMS is calling

    "early AMD64 and Alpha processors were designed to be pin compatible."

    Close enough. See Athlon, Hypertransport, and such.

    Start at e.g.

    "The Athlon architecture also used the EV6 bus licensed from DEC as its main system bus. Intel required licensing to use the GTL+ bus used by its Slot 1 Pentium II and later processors. By licensing the EV6 bus used by the Alpha line of processors from DEC, AMD was able to develop its own chipsets and motherboards, and avoid being dependent on licensing from its direct competitor."

  20. qwert1234sd

    Not so smug now are you?

    Where is DOC HOLLOWOOD now? Hahahahahaha

  21. Whoisthis


    Just got myself a new laptop in the boxing day sales...

    Is the 8th gen series ok? Could not find info anywhere. Specifically Intel® Core™ i5-8250U Processor

    Thanks pals

  22. JonHendry

    Re: Typical

    I think the 8th gen are okay.

  23. J J Carter Silver badge
    Big Brother

    Those pesky kids

    NSA/GCHQ/Mossad/PLA - "Oh, cock!"

  24. The Unexpected Bill

    What about fringe makers of x86/x64 CPUs?

    I'm greatly curious to know how or if companies like VIA (or maybe even DM&P) and their microprocessor products might be affected by this.

  25. J J Carter Silver badge

    Old skool....

    Looks like I'll be keeping my o/ced Q6600 workstation for a while yet...

  26. Ryan 7

    Re: Old skool....

    They're affected too...

  27. Anonymous Coward
    Anonymous Coward


    Isnt that why intel was better at benchmarks basically? And why most of people took the bait ? Im curious how benchmarks will look after the kernel fixes.

  28. Aitor 1 Silver badge

    Re: Intel.

    It seems they have decided to penalize all processors, inuding amd... now, they will use certain optimizations on intel micros so tjey only het about 18% slower. So amd will go 30% slower for no reason at all.

  29. Alan J. Wylie Silver badge

    Re: Intel.

    all processors, inuding amd

    This post on the Linux Kernel Mailing List, from Tom Lendacky at AMD says "AMD processors are not subject to the types of attacks that the kernel page table isolation feature protects against"

  30. Glad Im Done with IT

    Lots of testing work to be done then?

    As it is .Not spends about 30% in kernel according to TaskManager when loaded and working hard, how much will this cripple .Not, M$ pushes the fact that the code is secure, and this security is done in the kernel.

    It is certainly going to be amusing to watch the fallout from this,

  31. ilmari

    Re: Lots of testing work to be done then?

    It's the move to and from kernel that is penalized, time spent inside kernel and time spent outside kernel isn't penalized. Of course, hardly any system monitoring programs will tell you how many syscalls or context switches different programs cause.

  32. LewisCowles1986

    Nobody Else pissed about the God reference?

    > Think of the kernel as God sitting on a cloud, looking down on Earth. It's there, and no normal being can see it, yet they can pray to it.

    No I won't because I understand how a fucking kernel works. This is a remarkably stupid comparison; especially when we know how kernels work. We can evidence their existence, there are books relating to the design of them by mere mortals. They do not care about trivial areas of our lives!

    I'm more mad about this than the 20-30% of CPU limiting that's going to go on.

  33. This post has been deleted by its author

  34. Anonymous South African Coward Silver badge

    *slow clap*

    And this hoo-haa triggered this memory of the Usenet Oracle and Windows 95...

    The original can be found here :

    The Usenet Oracle has pondered your question deeply.

    Your question was:

    > O great Oracle, the one who sees all and knows all, please accept

    > this humble question from thy grovelling supplicant...


    > Why is Windows 95 Beta so bug-ridden it's not funny?

    And in response, thus spake the Oracle:

    } THE SCENE: A dark antechamber of the Gates estate, dimly lit by three

    } 20" monitors suspended from the ceiling. In the middle of the room is

    } a Pentium/100Hz, sheathed in a black casing. Three programmers dance

    } around the machine, chanting horribly. Their pale, clammy complexion

    } is cast hideously by the light of the monitors, rendered even more

    } repugnant to the watchful eye bye the 60Hz flicker of the monitors.


    } FIRST PROGRAMMER: Thrice the brinded net hath mewed.


    } SECOND PROGRAMMER: Thrice, and once the Warp-pig whined.


    } THIRD PROGRAMMER: MacHarpier cries. 'Tis time, 'tis time!


    } FIRST: Round about the terminal go;

    } In the poisoned upgrade throw.

    } Code, which by a student done

    } In minutes numbering sixty-one.

    } Run-time error, protection fault,

    } Crash ye first, crash ye shalt.


    } ALL [as they dance around the Pentium]:

    } Double, double, toil and trouble;

    } Tempers burn and data bubble.


    } SECOND: Fillet of a Sound Card bake,

    } In the Pentium no sound make;

    } Point of arrow, click of mouse,

    } Scream of user, frightened spouse,

    } OS/2's net use appeal,

    } Steve Jobs' look and Wozniak's feel.

    } For a charm of powerful trouble,

    } Like a hell-broth boil and bubble.


    } ALL: Double, double, toil and trouble;

    } Tempers burn and data bubble.


    } THIRD: Click "Start" button, speed of slug,

    } You would think you forgot the plug.

    } Multitasking, ha ha ho

    } If just one worked you'd be good to go.

    } This should grab those straggling few

    } Who aren't using DOS 6.22.

    } Now we shall the Mac eclipse,

    } While curse words cross our users' lips.

    } Leave the errors in so we can fix

    } And sell more...Windows 96!

    } And so we will release the Beta

    } For corruption of their data.


    } ALL: Double, double, toil and trouble;

    } Users buy, our profits double.


    } SECOND: Compile it with errors through,

    } Since the users have no clue.


    } [Enter BillGate to the other three programmers.]


    } BillGate: O, well done! I commend your pains,

    } And everyone shall share i' the gains.

    } And now about the program get,

    } But NEVER use it on OUR net.

    } Security is scarce put in.

    } [Beeps of PONG heard in the background.]

    } [Exit BillGate.]


    } SECOND WITCH: By the usage of my UMBs

    } Wicked Windows this way comes.

    } Open locks,

    } Whoever knocks!


    } [Fade to black.]


    } Remember, Obsolescence isn't an accident, it's an art form.


    } You owe the Oracle a signed, handwritten manuscript of MacBeth, and a

    } copy of the Windows upgrade for the P6.

  35. Philip Mather

    "PS: It appears 64-bit ARM Linux kernels will also get a set of KAISER patches,"

    Why has no one asked the most critical question... do I need to patch my Pi?

    Also, given the number of recent SNAFU's like this and Apple's login cock-up etc... I'd like to request a new +1 level of FAIL icon so that we can ring in 2018 with a new, appropriate level of numbnuttedness that the existing FAIL icon er... fails to encapsulate this new level.. Something like a double face palm icon?

  36. Anonymous Coward
    Anonymous Coward

    Typical Intel

    Many years ago when I was a hardware developer we used to call this the Intel Factor. In the spec sheets you used to get min / typical / max figures. You knew that when the production chips came to replace the test ones the figures would be the least advantageous. You had to always design for the very worse case + 10%

  37. ForthIsNotDead Silver badge

    Can I return my laptop?

    And for that matter, my 8 racks of Intel-based servers in the server room?

    Seriously, that was my first thought.

    If this were a car, and, under certain circumstances the brakes were applied without instruction from the driver, there would be a recall, and the problem would be fixed, with the manufacturer taking the financial hit.

    Why is it different with computer hardware? Why does the world just shrug its shoulders and just go "Oh well"?

    I've got a lovely Lenovo I3 laptop that runs Linux Mint beautifully, and I'm delighted with it. This has majorly pissed me off.

    In the server room, we run racks of Wintel HP servers running mission-critical SCADA software, and it looks like we're suddenly going to get a lot less bang for our buck.

    Why can't we return them the manufacturer, who in turn returns them to Intel?

    It's a rhetorical question, I suppose. I mean, what would they be replaced with, since Intel has no iron that, you know, actually works *properly*.

    But that's the point, isn't it. Why should we put up with this?

    Mistakes happen, of course. But there's no reason why we should just "put up with it".

  38. Anonymous Coward
    Anonymous Coward

    Unusual stock trades

    Intel's CEO dumped a load of stock in late November, and it was considered odd even before this news broke...

  39. James 47

    Re: Unusual stock trades

    This is most likely due to changes in US tax law. Goldman Sachs also distributed bonuses early for the same reason.

  40. Lee D Silver badge

    Re: Unusual stock trades

    Correlation is not causation.

  41. Tom 7 Silver badge

    Re: Unusual stock trades

    What? Goldman Sachs distributed bonuses early to avoid the lower tax rates?

  42. Mystic Megabyte Silver badge

    Back from the dead

    I was going to throw out two old HP AMD dual core laptops. Now I think I'll just replace the backlights and keep them. (they run Ubuntu or Mint perfectly well) In the meantime maybe it's safer to browse the web with a Raspberry Pi than this Lenovo with Intel inside.

  43. Giles Jones Gold badge

    Class Action

    Hopefully a lot of people are going to sue.

    Intel is getting complacent again, good job AMD have had a bit of a revival.

  44. Alan J. Wylie Silver badge

    kernel patch from early December

    Author: Dave Hansen <>

    Date: Mon Dec 4 15:07:34 2017 +0100

    x86/mm/pti: Disable global pages if PAGE_TABLE_ISOLATION=y

    Global pages stay in the TLB across context switches. Since all contexts share the same kernel mapping, these mappings are marked as global pages so kernel entries in the TLB are not flushed out on a context switch.

    But, even having these entries in the TLB opens up something that an attacker can use, such as the double-page-fault attack


  45. Third Electric

    Intel CEO insider trading?

    Looks like the CEO of Intel dumped most of his stock 2 days before this news dropped!

    Isn't that insider trading?

  46. Brian Morrison

    Re: Intel CEO insider trading?

    Almost certainly not, Executive Officers of corporations are required to announce share sales in advance according to a set timetable, they can't just dump it on a whim.

  47. Anonymous Coward
    Anonymous Coward

    Handbrake users beware

    For thos who use Handbrake to do video conversions, this will really hit you. Lots of CPU and tons of I/O.

    Now, where's that new PC I promised myself for new year.....

  48. ilmari

    Re: Handbrake users beware

    Funny, I thought video conversion would be minimally hit, as it consists mostly of:

    read(very many bytes); process (very long cpu intensive code); write(very many bytes)

    Where, if the read and write are implemented as sending big requests to the kernel, should be minimally affected. The processing portion of it is surely 99% of the whole processing time anyway?

    I could believe things like a database would slow down, when it's hopping all over the place on disk looking for/writing data. I could believe facebook slows down alot, because browsers are doing lots of itsy bitsy tiny reads and writes to both disk and net, and lots of small updates of the screen to animate all the gifs and what not.

  49. BinkyTheMagicPaperclip Silver badge

    Re: Handbrake users beware

    It's already been established on Phoronix that games are not affected - if it's mostly user mode code there isn't going to be a noticeable impact. I would have thought video editing/transcoding also fit into that category.

    Personally I'm more worried about virtualisation.

  50. EduQuint

    Which exact Intel processors models are affected by this kernel leak problem?

    I could not find any reference to this list of processor models anywhere in the Net,


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