Comment 0 for bug 1958284

With systemd v245 as shipped with 20.04, the shutdown sequence does not use the value of `DefaultTimeoutStopSec` to wait for remaining processes, it instead uses the compiled in default of 90s.

This is most visible with services that use `KillMode=process` (docker, k8s, k3s, etc...), especially if the remaining processes do not handle `SIGTERM` or choose to ignore it.

For example:
```
[ OK ] Finished Reboot.
[ OK ] Reached target Reboot.
[ 243.652848 ] systemd-shutdown[1]: Waiting for process: containerd-shim, containerd-shim, containerd-shim, fluent-bit

--- hangs here for 90s even if DefaultTimeoutStopSec is set to a lower value ---

```

The bug has been fixed upstream here: https://github.com/systemd/systemd/commit/7d9eea2bd3d4f83668c7a78754d201b22

Marc was kind enough to package the patch for 20.04 so I could test it (https://launchpad.net/~mdeslaur/+archive/ubuntu/testing/+sourcepub/13210617/+listing-archive-extra) and with that package, I can confirm that it indeed fixes the issue.

Here's a few github issues I stumbled upon while trying to debug this, along with a short writeup of the workaround I ended up using:

- https://github.com/moby/moby/issues/41831
- https://github.com/k3s-io/k3s/issues/2400
- http://localhost:8000/debugging-90s-hangs-during-shutdown-on-ubuntu-2004.html

Of course, it would be much better if all the processes would properly handle `SIGTERM`, but having a way to enforce a maximum wait time at shutdown is a decent workaround.

Given that the patch is relatively simple, would it be possible to add it the package for 20.04?

Thanks