(But in practice, we mostly rely on the fact that if you are in Google Cloud and specify a minimum CPU version, Google masks CPUID in that VM to exactly match that CPU, even if the underlying hardware is newer. They do this so live-migration of the whole VM works, but it also helps for process migration. I'm not sure where this is specifically documented but see e.g. https://stackoverflow.com/a/44507857 .)
(But in practice, we mostly rely on the fact that if you are in Google Cloud and specify a minimum CPU version, Google masks CPUID in that VM to exactly match that CPU, even if the underlying hardware is newer. They do this so live-migration of the whole VM works, but it also helps for process migration. I'm not sure where this is specifically documented but see e.g. https://stackoverflow.com/a/44507857 .)