is it just me or did SPECTRE manifest @halvarflake's "weird machine" concept in real hardware? i hope someone's already working on a paper about the computational power of this machine.
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and if so, this still wouldn't really be "programming the weird machine", but "programming the transitory machine" or so
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only reading the output would be weird
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I don’t think anything about either attack is a “weird state” nor is it some metastability or not fully enumerated entry in an internal state machine. It’s all precisely behaving according to spec, it’s just leaking information.
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Today its D cache and branch predictors, tomorrow it will be attacks against other parts of the machine. We have seen even papers showing how instruction sequences can damage machine life due to internal pipeline transitions they can force. There are so many possible vectors.
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"it depends". For assembly-level userspace code that reads privileged memory: The IFSM is an x86 code interpreter fully respecting privileges, w von neumann sequentiality, and memory access independent of other threads / cores (as this is the security prop that people want).
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hardware & microcode try to emulate this, but almost constantly move through weird states violating the IFSM, only occasionally reverting to a sane state. Reading out secrets would be programming the w mach. But I admit: The situation that the emulator for ifsm is almost ...
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