> mitigations for newly discovered spectre-like attacks have to be done software side, but successive processor generations will bake those mitigations into the

> mitigations for newly discovered spectre-like attacks have to be done software side, but successive processor generations will bake those mitigations into the silicon to reduce the performance penalties associated with software fixes. This is not correct. Spectre-like bug in the same privilege domain (as to the CPU) is just unfixable. Meltdown, L1TF etc were fixed in hardware because they leak data across hardware enforced privilege domains (i.e. userspace/kernel/enclave), in this sense it is a hardware bug. In case of browser, the CPU feature is "CPU is eager to leak arbitrary data in the same address space even if on the face the code does not seem to do it". This can't be fixed in the hardware because it's not a hardware bug: there's no hardware implemented security boundary, it's purely software defined.