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Comment Re:You realize (Score 1) 64

Currently, yes. But cryptomining could also be a boon to green energy. Right now, you have coal and nuclear that can provide a baseload, hydro and gas that can provide variable load. And hydro has been mostly maxed out, whenever it's already been built whenever it's reasonable. Solar and wind only provide intermittent power and thus can't be relied upon. We should absolutely build them to reduce the emissions of gas plants when renewables do provide power, but we have to keep our existing plants as well as a backup. But now we have a chance to go 100% nuclear, that is have enough nuclear energy for peak power instead of just the baseload, and then use the excess energy for cryptomining. Cryptocurrencies could subsidize a future where all have reliable and cheap electricity without any carbon emissions.

Comment Re:Encrypted Memory (Score 3, Informative) 115

Randomly flipping bits is literally all that rowhammer does. It's not a surgical strike, more like monkeys on a typewriter. The rowhammer based proof of concepts that I've seen basically just targeted the memory that a privileged process runs in, hoping that one of the flips they introduce will be the address of a jump, and the bitflipped address will point to an area of memory they control. This kinda worked with 32bit systems where usually every address was valid, but even there a successful attack took about 5-10 hours and was anything but subtle. But 32bit systems were already being phased out by the time rowhammer was discovered, and on 64bit systems you have a much bigger chance of just crashing whatever you are hammering instead of hijacking it. Which is why rowhammer has remained, and probably will remain a purely academic attack,

Comment Carrot instead of stick (Score 5, Insightful) 101

Bullying countries into reducing their carbon footprint doesn't work, carbon taxes and carbon tariffs don't work. What would actually work is focused research on making carbon-free technologies cheaper than fossil alternatives. This used to be unrealistic, but we are at a point now where any major power could spend less then the economic hit from the emission reduction and develop economic alternatives to pretty much any fossil use case within a decade. It's a lot easier to convince others to lower their emissions when it's the cheaper option.

Comment Re:Telemetry (Score 1) 23

I was under the impression that blind people are the biggest userbase of voice assistants. I always explained the popularity of smart speakers by the fact that the blind have been largely left out of the computing revolution. So it would be quite surprising to me if they only represented an insignificant fraction of voice assistant users, because I find it hard to believe that so many sighted people would subject themselves to such a horrible interface.

Comment Re:These articles are rubbish (Score 1) 416

Reliability isn't just about getting the correct answer, it's about always getting the correct answer within a certain amount of time. CPUs can be incredibly fast when they are given a large workload, but suck at intermittent tasks. You can think of this as the difference between latency and bandwith. Microcontrollers can guarantee that simple calculations will always finish within a given short amount of time no matter what, which is why they are used in realtime systems. Also, controllers have to be close to whatever they are controlling, so replacing all of them with a single chip isn't an option.

Comment Re:These articles are rubbish (Score 2) 416

There are only four fabs that can make modern CPU-level chips (Intel, Samsung, GloFo and TSMC), and their capacity was already maxed out. Then AMD started usning TSMC instead of GloFo, and even Samsung and Intel started offloading some of their fabrication to them, not to mention GPU makers due to the crypto demand. So now you have a single fab creating half of the chips in the world, already barely able to meet demand, and then the pandemic hit. So in that case, the chip shortage is understandable, this has been a long time coming. On the other hand, there are dozens of small fabs capable of creating chips for the microcontrollers used in the automotive industry. So the reason for the shortage of those is a lot more complicated, and has to do with a bunch of reasons like lack of raw materials (chip manufacturing requires pure monocrystalline silicon which is also in short supply, and what there is has mostly been redirected towards higher value chips) and decreasing production due to lockdowns. But the biggest reason is that at the beginning of the pandemic car manufacturers halted production completely, leaving many of these small fabs in shitty situation where they had to either close down or find other customers. So now car companies are trying to restart production, their old suppliers are reluctant to do business with them because they have shown themselves to be unreliable partners. Using CPUs instead of microcontrollers isn't going to help with this, unless you want your 50 cent chips to cost 200 bucks. And microcontrollers still cost a lot less than that, but automakers aren't willing to pay a higher price than what they are used to. The reason for that is that contrary to what they say, car manufacturers aren't in a rush to ramp up production, because in these uncertain times they aren't sure if they will be able to sell the cars they make. But admitting that would make their industry look less compelling to investors, so instead they blame everything on the chip shortage.

Comment Re:So what is the real world use? (Score 1) 38

As far as I understand it's mostly about attacking kernel space stuff and hoping that a jump address flips and sends the IP to an area of memory that the attacker controls, thus giving them kernel privileges. As you might expext, this really only worked in 32bit systems which have their 4gb of ram maxed out. So the attacker would allocate all the available memory for themselves to maximize the chance of capturing a random jump, then start hammering and hope for the best. This process takes dozens of hours, so it's really only useful against servers or cloud infrastructure or something else that's on 24/7.
Now 32bit systems were already outdated when rowhammer was discovered, and in a 64bit system most random addresses will simply be invalid, which is why after all those years rowhammer is still only of academic interest.

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