Re:Did Windows 10 slow down with each feature update?
by johncolanduoni on Tuesday June 22, 2021 @12:09AM
(#27587897)
Or simply none of them were aware that the kinds of speculation they were doing were capable of producing exploitable vulnerabilities. It took security researchers a long time to find these issues, and the kind of speculation that the original Spectre and Meltdown exploited were well known outside of the chipmakers for over a decade. Intel was simply more aggressive at that particular avenue of performance improvement.
I hypothesize it could have come down to "well, we made this type of decision this way before, and the world didn't fall down, so we can probably make it that way again, right?" Since these aren't formally proven systems, to some extent deciding whether an optimization is safe is going to be a judgment call - and if you go for "well, if this assumption is false, we're already doomed because we did X elsewhere...", the results could look like this.
Or maybe not, I've never worked for a chip design house.
[1] - https://mlq.me/download/takeaway.pdf