CyrilBrulebois, At some point I should really investigate GRUB_DEFAULT, grub-reboot, and friends in a VM where I can control results (as opposed to the jack-of-all-trades machine I needed to debug with minimal downtime), but at least I managed to confirm that #Linux kernel regression in #SMART.
This is https://bugs.debian.org/1068675 meaning no more “HDD temperature” graph in #munin.