I've also found a message about this on the Debian mailing list which describes this problem as "just a really severe cosmetic issue (which can cause some functional difficulties in practice, because this appears in every terminal - virtual or otherwise - on the entire system)" which is reassuring, and raises the question of why such a minor problem has been made into such a major annoyance, but does not help me.
Because this will probably come up, my motherboard is an MSI X99A SLI Plus, my CPU is an Intel i7-6850K, and my graphics card is an Nvidia GeForce GTX 1060 6GB (also MSI) using the nvidia drivers. I suspect these are part of the problem as before rebooting I had mitigations applied for Spectre variant 2 and Meltdown, but not Spectre variant 1. After rebooting I have mitigations for all three. So I think there's something about my BIOS this update doesn't like, and it's pestering me about it. Adding to this hypothesis is message that flashed past on boot (I don't recall seeing it before), looking through the logs I believe this is it:
Code: Select all
Apr 13 20:08:01 tomoko kernel: [ 0.000000] [Firmware Bug]: TSC_DEADLINE disabled due to Errata; please update microcode to version: 0xb000020 (or later)
Apr 13 20:08:01 tomoko kernel: [ 0.625879] microcode: sig=0x406f1, pf=0x4, revision=0xb00001d
Apr 13 20:08:01 tomoko kernel: [ 0.626094] microcode: Microcode Update Driver: v2.2.
At this point I'm looking at a suggestion to add dmesg -n 1 to my .bashrc file just to get rid of this ****** message. i know that's not the right thing to do and I know it would probably suppress other message I should be paying attention to, but I also wouldn't even be considering it if this 'cosmetic issue' wasn't being pushed so hard by syslogd that I'm sure it'll drive me insane before long. So I'm hoping to find a fix here.
Edit: One small piece of good news is that I've now told Plasma to ignore all messages coming from the local system messaging service and when Yakuake emits a bell from a non-visible session. Doesn't help with the terminals but at least that's one source of annoyance silenced.