So is it a new stepping? If so that would be remarkably fast for a bug to be fixed in silicon. Otherwise why couldn't AMD issue a microcode update to fix the i

So is it a new stepping? If so that would be remarkably fast for a bug to be fixed in silicon. Otherwise why couldn't AMD issue a microcode update to fix the issue on older processors of the same stepping? I guess I'm not understanding how it could be a silicon fix so quickly, or how any other manufacturing defect on the package would cause such an issue.