linux-modules-nvidia-450-server-generic uninstallable

[dann frazier]

linux-modules-nvidia-450-server-generic appears to be uninstallable on bionic currently. I hit this on actual hardware, but here's a reproduction in lxd for a clean-room demonstration:

ubuntu@blanka:~$ lxc launch ubuntu:bionic 450srv
Creating 450srv
Error: Failed instance creation: Invalid instance name: Name must not be a number
ubuntu@blanka:~$ lxc launch ubuntu:bionic nv450srv
Creating nv450srv
Starting nv450srv
ubuntu@blanka:~$ lxc exec nv450srv -- apt update
Get:1 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB]
Hit:2 http://archive.ubuntu.com/ubuntu bionic InRelease
Get:3 http://archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB]
Get:4 http://security.ubuntu.com/ubuntu bionic-security/main amd64 Packages [1355 kB]
Get:5 http://security.ubuntu.com/ubuntu bionic-security/main Translation-en [269 kB]
Get:6 http://security.ubuntu.com/ubuntu bionic-security/restricted amd64 Packages [151 kB]
Get:7 http://security.ubuntu.com/ubuntu bionic-security/restricted Translation-en [20.4 kB]
Get:8 http://security.ubuntu.com/ubuntu bionic-security/universe amd64 Packages [1069 kB]
Get:9 http://security.ubuntu.com/ubuntu bionic-security/universe Translation-en [239 kB]
Get:10 http://security.ubuntu.com/ubuntu bionic-security/multiverse amd64 Packages [12.3 kB]
Get:11 http://security.ubuntu.com/ubuntu bionic-security/multiverse Translation-en [2908 B]
Get:12 http://archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]
Get:13 http://archive.ubuntu.com/ubuntu bionic/universe amd64 Packages [8570 kB]
Get:14 http://archive.ubuntu.com/ubuntu bionic/universe Translation-en [4941 kB]
Get:15 http://archive.ubuntu.com/ubuntu bionic/multiverse amd64 Packages [151 kB]
Get:16 http://archive.ubuntu.com/ubuntu bionic/multiverse Translation-en [108 kB]
Get:17 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 Packages [1681 kB]
Get:18 http://archive.ubuntu.com/ubuntu bionic-updates/main Translation-en [360 kB]
Get:19 http://archive.ubuntu.com/ubuntu bionic-updates/restricted amd64 Packages [169 kB]
Get:20 http://archive.ubuntu.com/ubuntu bionic-updates/universe amd64 Packages [1672 kB]
Get:21 http://archive.ubuntu.com/ubuntu bionic-updates/universe Translation-en [352 kB]
Get:22 http://archive.ubuntu.com/ubuntu bionic-updates/multiverse amd64 Packages [31.4 kB]
Get:23 http://archive.ubuntu.com/ubuntu bionic-updates/multiverse Translation-en [6920 B]
Get:24 http://archive.ubuntu.com/ubuntu bionic-backports/main amd64 Packages [10.0 kB]
Get:25 http://archive.ubuntu.com/ubuntu bionic-backports/main Translation-en [4764 B]
Get:26 http://archive.ubuntu.com/ubuntu bionic-backports/universe amd64 Packages [10.3 kB]
Get:27 http://archive.ubuntu.com/ubuntu bionic-backports/universe Translation-en [4588 B]
Fetched 21.4 MB in 3s (6391 kB/s)
Reading package lists... Done
Building dependency tree
Reading state information... Done
7 packages can be upgraded. Run 'apt list --upgradable' to see them.
ubuntu@blanka:~$ lxc exec nv450srv -- apt install linux-modules-nvidia-450-server-generic
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 linux-modules-nvidia-450-server-generic : Depends: nvidia-kernel-common-450-server (<= 450.51.06-1) but 450.80.02-0ubuntu0.18.04.3 is to be installed
E: Unable to correct problems, you have held broken packages.

[Francis Ginther (fginther)]

This should be resolved now that the linux-restricted-modules which generate `linux-modules-nvidia-450-server-generic` have been released. It was a consequence of the nvidia driver packages being released to the archive prematurely and the time it takes for a kernel update to advance through the publication process. Both are process problems and can lead to this package install failure.

The nvidia driver packages should have had a "release hold" applied to prevent the premature release. Unfortunately, this is a manual process and was missed. One thing we will do as part of a retrospective for this release is determine if the release infrastructure or other tooling can be used to enforce this in the future.

I'm setting this to 'invalid' as the install issue with linux-restricted-modules has resolved itself.

[Francis Ginther (fginther)]

Actually, I'm going to set this to 'triaged'. We can then use this as the motivation for getting the `release hold` issue fixed.