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Is it time for open processors?

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131–140 of 236 posts

Re: Is it time for open processors?

#131
post #34

The problem is less about openness itself and more about quality of auditing. Open isn't a magic bullet. As I understand, these latest CPU vulnerabilities were in the spec themselves. You could've found them by reading the manual. See what good that did us. But I posit that open projects do better with audits than closed because they are more likely to have open audits as well, and an open audit is harder to ignore o…

As I understand it, according to an article that was posted here a day or two ago, Meltdown was in fact discovered by a young Google engineer poring over the x86 manual.

Yes. A 22 y/o guy.

Re: Is it time for open processors?

#132

Of course it is! What is this question? No, man, not yet. Everyone has a thing just for the closed ones. Instead of asking "Is it time...?" you just do it when it's time! Damn those click baits. Although, open as in OpenSSL made a bad name for open source, because without critical audits there is even less security in open , because then it might be wide open instead! In open source, when a thing is made and it works…

"What is this question?"

They're not asking if it would be nice to have, they're asking if it can be economically feasible now. If there isn't going to be a very large use case for open but inferior processors, a lot of money will be lost by anyone investing. That isn't a problem with software.

Re: Is it time for open processors?

#133
post #84
post #80

Earlier quoted context omitted.

I agree, the single, superfast CPU model is outdated. It's a shame that multiprocessor programming is hard (or is it? It might also just be a vicious circle: 'not many people do MPP because the facilities suck because not many people do MPP').

Look at the way the Amiga did it. The CPU was effectively a peripheral for the system controller known as Agnus. https://en.m.wikipedia.org/wiki/MOS_Technology_Agnus

Thats what the north/southbridge does, off-loading the CPU from all sorts of tasks (even if some of the tasks moved into the CPU die since the classic definition of north/southbridge was set)

Re: Is it time for open processors?

#134
Are you kidding? How many undocumented processor instructions and undocumented processor operating systems do what with your data. Imagine a world with transparent CPUs and you are imagining a world without mass data collection.

Re: Is it time for open processors?

#135

I would love to play with a RISC-V unit. But like one they linked too it was limited on memory and very expensive compared to other modern Aurdino compatible boards.

If you're really just looking to have fun and learn, $60 is nothing. You can burn through that at Dave & Busters in 15 minutes playing games. They also say it's the "fastest Arduino-Compatible dev kit" but I don't know enough about the space to know how accurate that is.

Re: Is it time for open processors?

#136
post #34

The problem is less about openness itself and more about quality of auditing. Open isn't a magic bullet. As I understand, these latest CPU vulnerabilities were in the spec themselves. You could've found them by reading the manual. See what good that did us. But I posit that open projects do better with audits than closed because they are more likely to have open audits as well, and an open audit is harder to ignore o…

> Open isn't a magic bullet. But closeness makes it extremely difficult to find actual backdoors left on purpose. Open processors would be a first step in the right direction.

remember, hacker will always find the backdoors first if we open source!

Re: Is it time for open processors?

#137
post #106
post #72

Earlier quoted context omitted.

I'd pay good money for an open and simpler platform to run my security-critical tasks that don't require top performance. Auditing a modern high-end CPU is probably a huge task even if you have access to the HDL because of how complex they are. A simpler design (RISC, no out-of-order execution, basic branch prediction and prefetching...) ought to be fast enough with modern lithography to browse the web, send emails a…

Why give up on performance? IA-64 ( https://en.wikipedia.org/wiki/IA-64#Architecture ) already exists, with its explicitly parallel instruction set, which leaves branch prediction and speculative execution up to the software. So you can still get many of the performance benefits, but it's under control of the software, giving a lot more flexibility for being able to mitigate or eliminate these kinds of issues. I thin…

Most Itanium implementations had hardware branch predictors+predicates.

Re: Is it time for open processors?

#139

I know that there are probably a billion technical hurdles for this, but in my perfect universe, CPUs would all be FPGA based; at that point, couldn't updates be almost as simple as a software update? I know that laws of physics kind of preclude this idea, but a guy can dream.

Then you can increase the power consumption of all electronics by 50+% and halve the processing power. And that is optimistic.

Yeah, hence my "laws of physics" thing at the end. I am just saying that it would be interesting if that was something reasonable to do.

Re: Is it time for open processors?

#140

I know that there are probably a billion technical hurdles for this, but in my perfect universe, CPUs would all be FPGA based; at that point, couldn't updates be almost as simple as a software update? I know that laws of physics kind of preclude this idea, but a guy can dream.

Then you can increase the power consumption of all electronics by 50+% and halve the processing power. And that is optimistic.

I appreciate what you're saying, but for devices with long lifetimes things may not be so clear. Consider a wifi device with a >15 year lifetime. Let's say such a device was built with SDR and FPGA, it conformed to 802.11b, and it used twice the power of an equivalent ASIC design. But 15 years later, this device was able to upgrade in software to 802.11ac, and so it was able to take advantage of spatial multiplexing and higher-order modulation to lower its power usage. So now this device uses twice as much power as an equivalent 802.11ac ASIC, but maybe it's more power efficient than that 802.11b ASIC from 15 years earlier.

I guess what I'm saying is that by allowing a device to upgrade in software to more power-efficient designs, you might claw back some of the efficiency lost by using an FPGA when you consider the entire product's lifetime.

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