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+ - x86 Computation Without Executing Any Instructions->

Submitted by jones_supa
jones_supa (887896) writes "Trust Analysis, i.e. determining that a system will not execute some class of computations, typically assumes that all computation is captured by an instruction trace. A team at Dartmouth College shows that powerful computation on x86 processors is possible without executing any CPU instructions. They demonstrate a Turing-complete execution environment driven solely by the IA32 architecture’s interrupt handling and memory translation tables, in which the processor is trapped in a series of page faults and double faults, without ever successfully dispatching any instructions. The 'hard-wired' logic of handling these faults is used to perform arithmetic and logic primitives, as well as memory reads and writes. This mechanism can also perform branches and loops if the memory is set up and mapped just right. The lessons of this execution model are discussed for future trustworthy architectures."
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Comment: Re: Hand over your fingerprint! (Score 1) 773

by root_42 (#44816961) Attached to: Apple Unveils iPhone 5C, iPhone 5S

Look at it from the NSA/FBI's point of view: they already have backdoor access to your phone's data, so the fingerprint scanner isn't about keeping Them out, but about securing biometric data from users voluntarily. If They tried to fingerprint or retina-scan a whole nation Themselves (like our troops do to occupied Afganistan and before in Iraq) there would be resistance; we only got away with it in Afghanistan and Iraq because we were an armed, occupying force. At home, they'll start integrating biometric scanners into cheap, gaudy (GOLD!) baubles so the Sheeple fingerprint themselves instead.

Your government already has my fingerprints. Every time I travel to the US, I have to leave my fingerprint at the border controls in the airport. Several years back, it was just a thumb print. But last time I went, it was all ten fingerprints.

Comment: Evolution (Score 1) 400

by root_42 (#44807935) Attached to: Interview With Professor Potrykus, Inventor of Golden Rice

I wonder if humans would evolve further, maybe producing their own beta carotene or Vitamin A? I do not condone the suffering of millions of people, but I wonder if giving our bodies everything in plenty is good in the long run (like generations).

Also, can't this deficiency be solved with existing crops and/or vegetables? The rice looks nice, though...

Comment: GNUStep is a great project (Score 2) 131

by root_42 (#44551443) Attached to: GNUstep Kickstarter Campaign Launched

I like this campaign. Objective C is continually in the Top 5 of the most widely used languages ( It is a very nice, simple object oriented C dialect. It is used on OS X and iOS, the latter of which is installed on hundreds of millions of devices ( Both operating systems heavily utilize Cocoa as their framework

Having better or even any Cocoa support on Linux would help to get developers to target both world. Linux on the one side, and iOS/OS X on the other side. I think this is well worth for all Linux users to chip in some money (even if it's only $1).

Comment: Re: Oh you and your sentimentality. (Score 3, Interesting) 390

by root_42 (#43518855) Attached to: Futurama Cancelled (Again)

This, this, a thousand times this! "The Late Philip J. Fry" is my favorite Futurama episode. So witty and full of good jokes and quotable lines. ("Just slow it down, I'll shoot Hitler out the window.")

But I must concur, the quality of the episodes varies in the last two seasons. I hope there'll be new, excitong shows around the corner.

Comment: Walk or cycle more, get a dog (Score 1) 635

by root_42 (#43176893) Attached to: Ask Slashdot: How Do You Stay Fit At Work?

I go to work by bus, but I still have to work ~1km to and from the bus. Also you could take a bicycle to work. Many workplaces offer showers for bike commuters (ours does). Also I have a dog and have to walk her 3x a day, rain or shine. Thus I get to about 6km of walking each day. Helps a lot.

Comment: Re:Reversed in America? (Score 2) 758

by root_42 (#42943279) Attached to: Is "Left" Vs. "Right" Hard-coded Into Your Brain?

Please stop. You're suggesting that the brains from one country are somehow different from that of another country. If we change 'country' out for 'race', it should be painfully obvious what the problem here is.

Maybe the brains actually are different from country to country, depending on cultural and environmental influences. What you shouldn't suggest is that either brain would be better than another. Difference doesn't mean that actually something has to be better, just that it works differently, while maybe achieving the same goal.

Comment: Re:Arsehole (Score 1) 1051

by root_42 (#42418393) Attached to: Linus Chews Up Kernel Maintainer For Introducing Userspace Bug

I wish my boss would show the same concern for the quality of our software, and scream at the programmers that break it every day. Unfortunately it doesn't happen, and other programmers end up fixing the broken code (and quietly grumbling) because otherwise they would not be able to do their jobs.

Sometimes harsh words can send a message better than a general "please check your code before you commit".

There is a difference between being concerned for software quality and humiliating someone in front of colleagues. If my boss would punish a workmate (or me) like that, I would be looking for a different job rather quickly if this behaviour wouldn't change rather quickly.

Nobody's gonna believe that computers are intelligent until they start coming in late and lying about it.