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A comment on Avoid speculative indirect calls in kernel. Parent comment

Re:Avoid speculative indirect calls in kernel by rst on Wednesday January 03, 2018 @09:35PM (#16067531)
Interacting terribly with CPU branch prediction is the whole point -- Spectre attacks work by messing with the branch predictor, to misdirect speculative execution onto paths that reveal information useful to the attacker. So, the point of this whole crazy dance is to effectively disable the branch predictor.
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Re:Avoid speculative indirect calls in kernel by revelation on Wednesday January 03, 2018 @09:39PM (#16067552)
Of course. But it needs spelling out, because branch prediction is essential to good performance and why todays CPUs can be much faster despite not reaching higher clocks. It's much more than just the cost of a few more instructions.
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