Spectre Attacks on AMD K7 Processors: Exploring the Possibilities
Published exploits? Not that I’m aware of.
Indications that it would be possible? Yes. The K7 family, like its Intel counterparts, is an out-of-order design with a branch predictor. Those are the two critical parts for performing a Spectre attack. You don’t need a cache-flush instruction to perform the attack, since you can get the same effect just by reading an area of memory you know the attack won’t access. In fact, this is exactly how the Javascript proof-of-concept clears the cache, since Javascript JIT doesn’t give access to clflush.