> microcode level detectors for particular proof of concepts No, they don't have enough microcode space for this, and the data paths in the CPU that Spectre an

> microcode level detectors for particular proof of concepts No, they don't have enough microcode space for this, and the data paths in the CPU that Spectre and Meltdown affect are not programmable with microcode. The microcode updates have been hamfisted, usually amounting to a massive hammer. E.g. the first "hardware fix" for variant 2 (branch target injection) was to make the BTB not shareable across hyperthreads. The fix worked. It was to completely disable the BTB for indirect branch predictions altogether. Ha! That'll confound any sharing of it! Intel's CPUs are completely riddled with side channels due to the way they implemented speculative rollback. They are kind of screwed.