update-initramfs stuck at 96% FATAL TO SYSTEM

[Snowhog]

The hung mdadm scan processes CANNOT be killed with kill -9 or -SIGKILL.

Apparently not.

[claydoh]

I'd report it as a bug if I could find where to do it Seems I never can find the correct "official" webpage to report something like this.

As this is an Ubuntu system/Ubuntu components, I'd start with Launchpad. You can assign multiple packages to a bug report, iirc. I'd go with initramfs-tools, and/or whatever triggered it to be run?
triaging will add appropriate component, or point the reporter where to go if it is somehow related to a Plasma package, or one of the few non-plasma related items neon builds.

[oshunluvr]

So even "kill -9 <somepid>" wouldn't work?

Nope. I tried kill -1, kill -KILL, and kill -SIGKILL

Nothing worked

[oshunluvr]

Bug filed on mdadm.

If /usr/share/mdadm/mkconf were configured to not scan srX devices this wouldn't happen.