There have been 5 kernel patch releases since 6.7.1-rc1 and there don't appear to be any problems with Zombieland mitigation.  We updated a few security-related patches, but I want to give this a few days of wider testing before publishing to stable.   Please post here in this topic, any issues you run across which are not present in 6.7.0 also - that is, issue that you think can be directly attributed to the microcode and/or kernel changes.   Version 6.7.1-rc2 2019-06-08