Intel processor bug

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Says any Intel processors made in the last decade is vulnerable.

Python Sweetness

The mysterious case of the Linux Page Table Isolation patches The mysterious case of the Linux Page Table Isolation patches

[Various errors and updates are addressed in Quiet in the peanut gallery]

tl;dr: there is presently an embargoed security bug impacting apparently all contemporary CPU architectures that implement virtual memory, requiring hardware changes to fully resolve. Urgent development of a software mitigation is being done in the open and recently landed in the Linux kernel, and a similar mitigation began appearing in NT kernels in November. In the worst case the software fix causes huge slowdowns in typical workloads. There are hints the attack impacts common virtualization environments including Amazon EC2 and Google Compute Engine, and additional hints the exact attack may involve a new variant of Rowhammer.
 
I see the updated errata states "may not affect AMD CPU's". I guess we wait for further clarification?
 
Originally Posted By: OVERKILL
I see the updated errata states "may not affect AMD CPU's". I guess we wait for further clarification?


But will they put these checks in software and check processor or just do the checks regardless.
 
For more detail on the software-side of things, specifically how it is being addressed in Linux, there's a nice thread on the Kernel Developers Mailing list found here . A gentleman from AMD chimes in in another thread indicating that AMD processors aren't susceptible to this bug and asks for their processors to be omitted from the patch. One of the dev's responds indicating that omission may not be a good idea, as not being affected by this bug doesn't mean that future exploits that are similar in nature will except AMD CPU's. Be interesting to see what that officially evolves into.

The biggest issue aside from the vulnerability itself seems to be the performance impact of the patches
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Will be interesting to see what, if anything, Intel has to say on the matter.
 
I had an old Compaq desktop with an AMD Sempron processor that ran 32 bit Linux distros much faster/better than my Gateway gaming desktop that had an Intel Q6600 CPU. Windows was much faster on the Intel chip however.
 
The latest AMD Stuff is freakin' awesome. Built a Ryzen 7 1700 system and it flies. Load up a few VM's and it doesn't know they are there.

EPYC is using less power and killing it in high performance workloads and in datacener type stuff.
 
Haven't built an Intel based system in probably 15 years. Everything has been AMD. For the price/performance ratio, it's hard to beat AMD.
 
I'm a big Intel fan but it wouldn't hurt for any opportunity to either level out the competition between the 2 majors, or to get a 3rd or 4th company in the mix. I HATE duopoly situations.
 
Originally Posted By: Reddy45
I'm a big Intel fan but it wouldn't hurt for any opportunity to either level out the competition between the 2 majors, or to get a 3rd or 4th company in the mix. I HATE duopoly situations.


There used to be Cyrix, LOL!
 
Originally Posted By: itguy08
AMD is on the record as saying their CPUs are not vulnerable.

Intel is in damage control mode:
https://www.barrons.com/articles/intel-r...&yptr=yahoo

Hopefully this will reduce their clout tremendously.


Yes, I mentioned that above. One of the guys from AMD chimes in about it in the Kernel dev mailing list.

I'll quote him here for the sake of clarity:

Originally Posted By: Tom Lendacky

AMD processors are not subject to the types of attacks that the kernel
page table isolation feature protects against. The AMD microarchitecture
does not allow memory references, including speculative references, that
access higher privileged data when running in a lesser privileged mode
when that access would result in a page fault.

Disable page table isolation by default on AMD processors by not setting
the X86_BUG_CPU_INSECURE feature, which controls whether X86_FEATURE_PTI
is set.

Signed-off-by: Tom Lendacky


From HERE.
 
Originally Posted By: PeterPolyol
Why am I not surprised about a fundamental hardware level security 'defect' from Intel specifically? :eyesroll:


It may also affect ARM. I'm waiting for further details to emerge before I cast judgement on Intel.
 
Originally Posted By: OVERKILL
Originally Posted By: Reddy45
I'm a big Intel fan but it wouldn't hurt for any opportunity to either level out the competition between the 2 majors, or to get a 3rd or 4th company in the mix. I HATE duopoly situations.


There used to be Cyrix, LOL!
I had a 486DX2-80 Cyrix processor in one of my computers from back in the day. My buddies Intel 486DX2-66 was a faster system playing the same games. I'm an AMD user these days though.
 
Originally Posted By: OVERKILL
Originally Posted By: Reddy45
I'm a big Intel fan but it wouldn't hurt for any opportunity to either level out the competition between the 2 majors, or to get a 3rd or 4th company in the mix. I HATE duopoly situations.


There used to be Cyrix, LOL!



The very first PC our family bought back in the day had a Cyrix processor. Crazy to think how far we have come.
 
I built a PC back in the day and used a Cyrix 6x86. May still have the processor sitting in a drawer.
 
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I remember Cyrix. Had decent chips back in the day - a little less performance than AMD or Intel but great value and some were even able to run fanless (486's) where the others needed fans.

Don't forget VIA also dabbled in x86 CPUs for a while there at the turn of the century.

Never ever been a fan of Intel. The only reason I have them is because I've got some Macs and because nobody builds a high spec AMD laptop, at least for now.
 
Originally Posted By: xxch4osxx
Originally Posted By: OVERKILL
Originally Posted By: Reddy45
I'm a big Intel fan but it wouldn't hurt for any opportunity to either level out the competition between the 2 majors, or to get a 3rd or 4th company in the mix. I HATE duopoly situations.


There used to be Cyrix, LOL!
I had a 486DX2-80 Cyrix processor in one of my computers from back in the day. My buddies Intel 486DX2-66 was a faster system playing the same games. I'm an AMD user these days though.


I'm on Intel, I've had a few AMD systems over the years but the stability of the Intel chipsets back when VIA, ALI and their ilk were the main game in town for AMD really soured me on them. I was actually not overly impressed when they procured good old Canadian ATI. I expected, predictably, that Intel would then buy NVidia. Apparently it was actually in the works, but the amount that NVidia believed they were worth versus what Intel wanted to pay for them was what ultimately led to that deal falling apart.

ATI has benefited significantly from a greater pool of resources however and I'm still very fond of their graphics products.


**Warning, tangent ahead**

Growing up in the infancy of the personal computer, there were all kinds of brands that came, went or were absorbed. There used to a much broader array of graphics card/chip manufacturers: Trident, Cirrus Logic, 3DFX, VIA, ALi, SiS, Matrox, S3, Chips & Tech, OPTi, Oak, Real3D, Rendition, SGI, Hercules...etc.

The CPU market was far less diverse, you had Intel, and then if you were cheap, you had AMD, VIA or Cyrix, all of which were a serious downgrade from a comparable Intel offering. Of course there were other processors available in the higher-end workstation and server market like the Alpha and SPARC stuff, but for us mere mortals, the three were our main focus.

Chipset-wise, if you bought Intel, you got Intel unless you chose to intentionally cheap-out there as well. If you bought one of the others you got somewhat of a wide variety of potentially poorly supported garbage that finding drivers for was sometimes a serious epic. AMD really seemed to make a go of fixing that with their SlotA chipset (which was rock solid) but then they abandoned the chipset market again, whilst Nvidia waded into the fray and you got weird half-supported GPU/Northbridge configurations with questionable southbridge offerings that would get their posteriors spanked by anything Intel produced. It wasn't until AMD and ATI were merged that this turned around.
 
I became an AMD fan when they came out with the 18um Athlon processors. That thing ran better and for a longer time than any Intel PIII/PIII Xeon/P4 box that I had at the same time.

Then I went to intel based mac and havent looked back.
 
Originally Posted By: OVERKILL

I'm on Intel, I've had a few AMD systems over the years but the stability of the Intel chipsets back when VIA, ALI and their ilk were the main game in town for AMD really soured me on them.


I think a lot of that had to do with Windows rather than the VIA chipsets. Been using AMD since the 486 days and had K5, K6, K62, Duron, and now the Ryzen. The VIA chipsets were pretty solid but had driver issues with Windows. On my Duron box, the machine that pushed me to Apple because of 98 and ME issues all the stability issues went away when I put Linux on it. It became rock solid.

Quote:
Growing up in the infancy of the personal computer, there were all kinds of brands that came, went or were absorbed. There used to a much broader array of graphics card/chip manufacturers: Trident, Cirrus Logic, 3DFX, VIA, ALi, SiS, Matrox, S3, Chips & Tech, OPTi, Oak, Real3D, Rendition, SGI, Hercules...etc.


I remember supporting that mess and those oddball drivers. It sucked...

Quote:
The CPU market was far less diverse, you had Intel, and then if you were cheap, you had AMD, VIA or Cyrix, all of which were a serious downgrade from a comparable Intel offering.


AMDs offerings were as good as or better than Intel. AMD actually was the 2nd source for 8086/8088 CPUs back in the day and their 286, 386, and 486 CPUs were as fast as if not faster than Intel's of the time. The K5 and K6 were faster in office type stuff but had a weaker FPU. The K62 aattempted to fix that but it's FPU was a little less. The Athlon was faster than Intel and was an awesome CPU.

Don't forget you owe the x86_64 instruction set to AMD who invented it and licensed to Intel. Intel was too busy with Itanium to try to extend X86.

Quote:
Chipset-wise, if you bought Intel, you got Intel unless you chose to intentionally cheap-out there as well. If you bought one of the others you got somewhat of a wide variety of potentially poorly supported garbage that finding drivers for was sometimes a serious epic.


Only past 486 was Intel in the chipset game. And even with the 486 and above there were other Vendors. IIRC VIA, SiS, and a few others did 486 and Pentium chipsets.

Aah the good old days - lots of good stuff and lots of junk....
 
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