My read is that vulnerable processors generally have to: 1. Have out of order execution 2. Have aggressive speculative memory load / caching behavior 3. Be a

My read is that vulnerable processors generally have to: 1. Have out of order execution 2. Have aggressive speculative memory load / caching behavior 3. Be able to speculatively cache memory not owned by the current process (either kernel or otherwise) 4. Have deterministic ways of triggering a speculative load / read to the same memory location 2 is probably the saving grace in ARM / low power land, given they don't have the power budget to trade speculative loads for performance (in the event they're even out of order in the first place). Caveat: I'm drinking pretty strong Belgian beer while reading through these papers.