I have been taking a daily look for any reports of issues with intel microcode updates over the last 30 days, and so far there are no reports of issues caused by these updates.
Due to the HT errata issue, these microcode updates had a lot more adoption than usual by users across most Linux distros, so they had a lot of extra exposure already. Version 20170511 shipped with stretch non-free, and we had no regression reports about it. It was also backported to jessie-backports, and even with everyone that installed it both in stretch and jessie due to the hyper-threading errata (about 2000 additional new installs according to popcon), there were no regression reports. It was widely installed on other distros, and I could not find any regression reports on Gentoo, Arch, Mint or Fedora, nor through Google searches. Version 20170707 only added new microcode for newer processors (Kaby Lake, and very recently launched Skylake server and Skylake-X), leaving all other microcodes unchanged from 20170511. Since the motherboards that support such processors were launched relatively recently, and Kaby Lake is quite close to Skylake firmware-wise as far as microcode and closely related platform modules, the chances of regressions due to outdated firmware are lower. Again, I can't find any regression reports at all related to this microcode update. There are several reports from Ubuntu users about sucessfull installs of both 20170511 and 20170707, since they're also evaluating it for SRUs as well. No regressions were reported so far: https://bugs.launchpad.net/ubuntu/+source/intel-microcode/+bug/1700373 Thanks! -- Henrique Holschuh