Since 2013, Hidehiro Kawai et al. has tried to push RAS features and bug fixes, originally developed for their mission-critical server for control systems, into the mainline kernel. In this presentation, he will talk about what sort of features are required for those servers, what have been done in the mainline, and what would be done in the next. He would like to share remaining issues to promote the activity. This is positioned as an update of Yoshihiro Yunomae's presentation in LinuxCon JP/NA in the last year.