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Earlier quoted context omitted.
I somewhat doubt that is still the case, with modern EDA tools.
I think they were maybe making a joke about whether you want to use the chip or not.
I don’t understand the Intel hate. It’s not like their engineers are dumb or lazy. This exploit is very hard to imagine before now. And it’s there because chip makers were trying to wring out more performance. It’s unfortunate if anythig.
From my perspective: I've been singing Intel's praises for the last decade as they regularly (for my own tests/usage) beat out AMD in performance, clock for clock if not dollar for dollar. With this recent news, I feel like part of the reason that Intel has been doing so well is that they have been _cheating_.
All processors (including AMD/ARM) since the early 90's have been using instruction pipelining. It's a universal performance improvement, not Intel cheating.
I don’t understand the Intel hate. It’s not like their engineers are dumb or lazy. This exploit is very hard to imagine before now. And it’s there because chip makers were trying to wring out more performance. It’s unfortunate if anythig.
theo de raadt of openbsd called this out, 10 years ago: https://marc.info/?l=openbsd-misc&m=118296441702631
I don’t understand the Intel hate. It’s not like their engineers are dumb or lazy. This exploit is very hard to imagine before now. And it’s there because chip makers were trying to wring out more performance. It’s unfortunate if anythig.
All other chipmakers are 'immune' to Meltdown precisely because the attack is obvious. Cache timing is hard, but speculating execution before checking permissions is plain dumb. If it was such a mythical attack why doesn't it work on anyone else's chips? Intel screwed up hard on this and I have no sympathy. Hopefully the incoming lawsuits will make up for the massive amount of money wasted for the performance losses
> We also tried to reproduce the Meltdown bug on several ARM and AMD CPUs. However, we did not manage to successfully leak kernel memory with the attack described in Section 5, neither on ARM nor on AMD. The reasons for this can be manifold. First of all, our implementation might simply be too slow and a more optimized version might succeed. For instance, a more shallow out-of-order execution pipeline could tip the race condition towards against the data leakage. Similarly, if the processor lacks certain features, e.g., no re-order buffer, our current implementation might not be able to leak data. However, for both ARM and AMD, the toy example as described in Section 3 works reliably, indicating that out-of-order execution generally occurs and instructions past illegal memory accesses are also performed.
I don’t understand the Intel hate. It’s not like their engineers are dumb or lazy. This exploit is very hard to imagine before now. And it’s there because chip makers were trying to wring out more performance. It’s unfortunate if anythig.
Well they did release their Coffee Lake generation chip after they already new about the exploit. Now i know it would take a lot for a major company to delay/cancel a release like that, but i think it could be argued that they were dishonest if they knew it would have a performance impact.
Earlier quoted context omitted.
The most recent ARM chips (cortex A75) are vulnerable.
Didn't know that. The chipmaking business is insular and pretty incestuous, I wonder if the same engineers built both speculative execution units. I've got a friend in CPU design and he's only got about 50 companies he can work for in the world where he could do the same job he does now
I don’t understand the Intel hate. It’s not like their engineers are dumb or lazy. This exploit is very hard to imagine before now. And it’s there because chip makers were trying to wring out more performance. It’s unfortunate if anythig.
> I should note that we kernel programmers have spent decades trying to reduce system call overheads, so to be sure, we are all pretty pissed off at Intel right now. Intel's press releases have also been HIGHLY DECEPTIVE. In particular, they are starting to talk up 'microcode updates', but those are mitigations for the Spectre bug, not for the Meltdown bug. Spectre is another bug, far more difficult to exploit than Meltdown, which leaks information from other processes or the kernel based on those other processes or kernel doing speculative reads and executions which are partially managed by the originating user process. Spectre does NOT involve a protection domain violation like Meltdown, so the Meltdown mitigation cannot mitigate Spectre.
> These bugs (both Meltdown and Spectre) really have to be fixed in the CPUs themselves. Meltdown is the 1000 pound gorilla. I won't be buying any new Intel chips that require the mitigation. I'm really pissed off at Intel.
[1] http://lists.dragonflybsd.org/pipermail/users/2018-January/3...
I don’t understand the Intel hate. It’s not like their engineers are dumb or lazy. This exploit is very hard to imagine before now. And it’s there because chip makers were trying to wring out more performance. It’s unfortunate if anythig.
However for unknown reasons it’s worse in Intel. They were not able to exploit the vulnerability to dump the kernel memory on AMD and ARM.
So I find the whole “Intel you suck” really out of line. I would not be surprised someone clever will come and figure out a Meltdown style attacks which works on AMD and ARM CPUs.
As Bruce Schneier says: “attacks always get better they never get worse”
google cache: https://webcache.googleusercontent.com/search?q=cache:jqSuv7...
Cleaner IPFS link: https://www.eternum.io/ipfs/QmQU1bCPsg7VY5puKqH6wZfAv1ZWBteK... By the way, here's a short script that will download a (full) page with wget, add it to IPFS (if you have a running daemon) and copy the Eternum link to clipboard: https://www.pastery.net/zxkzkc/