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Serious Intel CPU bugs (2016)

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Re: Serious Intel CPU bugs (2016)

#51

Post by nabla9 »

slivym wrote: post #13

As a former Intel employee this aligns closely with my experience. I didn't work in validation (actually joined as part of Altera) but velocity is an absolute buzzword and the senior management's approach to complex challenges is sheer panic. Slips in schedules are not tolerated at all - so problems in validation are an existential threat, your project can easily just be canned. Also, because of the size of the compa…

I thought that the secret of Intel's success is paranoia. Andy Grove's motto was "Only the paranoid survive" and he wrote a book with the same name.

Re: Serious Intel CPU bugs (2016)

#52

Post by _up »

dataflow wrote: post #4

Out of curiosity, if you notice a CPU bug in a computer under warranty, is there anything the vendor is usually obligated do, or are they under no obligation to do anything about a CPU bug? Is that considered a defect they have to handle? (Edit: I'm assuming the USA, and I'm assuming bugs that were not known to the vendor at the time of the sale.)

Apple recently had to replace Iphone batteries because there device became slougish. So there is precedent.

Re: Serious Intel CPU bugs (2016)

#53

Post by _0w8t »

I can only expect that future will be worse. It may be that VM providers will find it unprofitable to offer a VM capable of running generic native code. Another thing that security products for desktops like Qubes OS that rely on hardware isolation to run untrusted code may need to reconsider their business model.

Re: Serious Intel CPU bugs (2016)

#54

Post by Macha »

ckastner wrote: post #40
kuschku wrote: post #35

Earlier quoted context omitted.

The law applies to any sale between a consumer and a company, even one for free. It does also apply to software, but software vendors will rather refund you than fix it.

> The law applies to any sale between a consumer and a company, even one for free. There is no such thing as a free sale, and no, when you are gifted something, then you don't get the EU warranty protection.

I think it's more referring to offers like these:

* Buy One Get One Free * Free USB-C to A hub with your new Macbook Pro

I would expect the free item to be covered in these cases?

Re: Serious Intel CPU bugs (2016)

#55

Post by static_noise »

dspillett wrote: post #43
bwang29 wrote: post #3

Quote from article "We need to move faster. Validation at Intel is taking much longer than it does for our competition. We need to do whatever we can to reduce those times… we can’t live forever in the shadow of the early 90’s FDIV bug, we need to move on. Our competition is moving much faster than we are". Competition pressure could make a company's new product worse than (in this case, less stable than) their previ…

> "we can’t live forever in the shadow of the early 90’s FDIV bug" There is a valid point there though - if you are testing for testing's sake and not finding anything extra through the extra effort then you are wasting time and potentially worse: lulling yourself into a false sense of security. Testing should be done for utility, not just in response to fear - you need to test intelligently, not just test lots. Like…

Testing is not for finding bugs, testing is for preventing bugs. But otherwise you are right, it's hard to calibrate and further develop the testing procedure if you rarely find bugs. While you might wide awake on one eye you might be blind on seven others. It's usually the things you don't expect that kill you. So, some need to be paranoid, be very paranoid.

Re: Serious Intel CPU bugs (2016)

#56

Post by amdavidson »

_up wrote: post #52
dataflow wrote: post #4

Out of curiosity, if you notice a CPU bug in a computer under warranty, is there anything the vendor is usually obligated do, or are they under no obligation to do anything about a CPU bug? Is that considered a defect they have to handle? (Edit: I'm assuming the USA, and I'm assuming bugs that were not known to the vendor at the time of the sale.)

Apple recently had to replace Iphone batteries because there device became slougish. So there is precedent.

Apple didn't have to replace batteries, they chose to do it to quiet down the bad PR they were receiving.

When Intel issues a microcode update to slow down aging Skylake processors so that everyone goes out to buy Cannonlake, you might be able to draw a comparison.

Re: Serious Intel CPU bugs (2016)

#57

Post by mehrdadn »

dannyw wrote: post #49
dataflow wrote: post #4

Out of curiosity, if you notice a CPU bug in a computer under warranty, is there anything the vendor is usually obligated do, or are they under no obligation to do anything about a CPU bug? Is that considered a defect they have to handle? (Edit: I'm assuming the USA, and I'm assuming bugs that were not known to the vendor at the time of the sale.)

Under Australian law, it depends on if the defect is material, and if it would have reasonably changed your buying decision. A 30% performance reduction (like the page table isolation fixes) probably would be considered material.

> Under Australian law, it depends on if the defect is material, and if it would have reasonably changed your buying decision.

Interesting, so if you need that particular product (say it has something specific you need, e.g. a program that only runs well on Intel) and there is no competitor to it with that particular feature (e.g. AMD CPU runs the program poorly) then they can sell you as otherwise-defective of a product as they want and you cannot recover damages?

Or to put it another way, there is no notion of "I would have still bought it because I needed it but knowledge of the defect would have lowered its market value"?

Re: Serious Intel CPU bugs (2016)

#58

Post by _up »

amdavidson wrote: post #56
_up wrote: post #52

Earlier quoted context omitted.

Apple recently had to replace Iphone batteries because there device became slougish. So there is precedent.

Apple didn't have to replace batteries, they chose to do it to quiet down the bad PR they were receiving. When Intel issues a microcode update to slow down aging Skylake processors so that everyone goes out to buy Cannonlake, you might be able to draw a comparison.

Sorry maybe I used the wrong word "precendence". But there is a similarity and Apple is still beeing sued. And purely a PR move is also misleading.

Re: Serious Intel CPU bugs (2016)

#59

Post by int0x80 »

paulmd wrote: post #14

Denverton is much more complex than a "simple" Atom (performance of a C3958 is up to about half of an i5-7500 in single-thread, twice the total multi-thread performance). Avoton is really no slouch either. It's really not surprising that the incidence of bugs is increasing on those uarchs as the complexity grows. The Skylake/Kaby hyperthread bug has been fixed in microcode and is no longer applicable. It's perfectly…

>Gamers and compute-oriented workloads won't be hurt hardly at all.

Actually KPTI doesn't only affect syscall but also interrupts. It makes interrups slower, which affects every workload.

Re: Serious Intel CPU bugs (2016)

#60

Post by matwood »

philjohn wrote: post #23
aristidb wrote: post #20

Earlier quoted context omitted.

The very article mentions at the bottom that AMD has its fair share of nasty bugs recently, too. If anything, I would expect AMD to spend even less effort on validation (because they are not flush with cash).

Or, because they're not flush with cash, they go for a simpler to verify design. Remember, a lot of the Zen arch was developed by Jim Keller, who is the brains behind the Athlon 64.

I loved my Athlon 64. IIRC, it ran hot as hell, but the price/performance was amazing.
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