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Trump Dissolves His Fraudulent "Election Integrity" Commission

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Nerdy Fish1/03/2018 6:09:54 pm PST

Techno-babble behind the spoiler tag…

Spectre and Meltdown are variations on the same theme; Meltdown affecting an Intel-specific implementation, Spectre attacking the general concept, which applies to all modern processors. The root cause is that anything done in software is slow, and so the major leaps in processing speed have been hardware trying to do things that are usually done in software. The concept at issue here is called “speculative execution”. A computer program takes lots of different paths based on conditions; if this, then that, etc., etc. Modern processors store a history of these paths, and if it sees something it thinks is familiar, it goes ahead and executes those instructions before the program actually calls for them to be executed, in the background, anticipating that the result will be needed later and can be instantly recalled. If it isn’t needed, the processor has lost nothing by executing those instructions off-cycle, and the result is thrown away. The exploit is involved in setting the program up to read an area of memory it is not allowed to read; the processor goes ahead and reads that data off-cycle while the operating system checks to see if the program is actually allowed to read that memory. The malicious program then interrupts the processor and copies that pre-fetched data out before the operating system denies the request and causes the data to be erased.