[Bug 2051457] Re: Jammy 22.04.3 gcc compiler no longer builds modules for 6.5.0 kernel series

[Ubfan]

There may be a few issues involved here.
Hardware RTX3080, driver Nvidia 535.146.06? and 535.154.05
1) Phasing of the Nvidia drivers. When the hwe package update to the 6.5 kernel occurred, Nvidia package(s) were held back due to phasing. The Nvidia module could not be built, so black screen. Fall back to the older 6.2 kernel, of course still worked.
2) Source of the Nvidia modules and script/build files. With only the standard repos (no graphics-drivers ppa), forcing the held-back phased Nvidia packages worked, and the Nvidia module build successfully. Only after seeing this problem, looking around, I see gcc-12 is installed, but not manually by me. The apt list output shows an automatic installation:
$ apt list g{cc,++}-*{0,1,2,3,4,5,6,7,8,9} --installed
Listing... Done
g++-10/jammy-updates,jammy-security,now 10.5.0-1ubuntu1~22.04 amd64 [installed]
g++-11/jammy-updates,jammy-security,now 11.4.0-1ubuntu1~22.04 amd64 [installed,automatic]
gcc-10/jammy-updates,jammy-security,now 10.5.0-1ubuntu1~22.04 amd64 [installed,automatic]
gcc-11/jammy-updates,jammy-security,now 11.4.0-1ubuntu1~22.04 amd64 [installed,automatic]
gcc-12/jammy-updates,jammy-security,now 12.3.0-1ubuntu1~22.04 amd64 [installed,automatic]
gcc-9/jammy-updates,jammy-security,now 9.5.0-1ubuntu1~22.04 amd64 [installed,automatic]


I presume if the Nvidia modules were not phased, and installed with the 6.5 kernel, the gcc-12 would have been downloaded too, and everything would work as expected. The only manual action I took was to add the option to the upgrade: sudo apt -o APT::Get::Always-Include-Phased-Updates=true upgrade

I don't see any depends or reverse depends on the kernel or Nvidia
packages which would explain how the gcc-12 showed up, so maybe in some
install script.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to gcc-defaults in Ubuntu.
https://bugs.launchpad.net/bugs/2051457

Title:
  Jammy 22.04.3 gcc compiler no longer builds modules for  6.5.0 kernel
  series

Status in gcc-defaults package in Ubuntu:
  Confirmed

Bug description:
  Since Jammy went to the 6.5.0 kernel series, that kernel series was
  compiled with gcc-12. The previous 6.2.0 series kernels were compiled
  with gcc-11.

  The current version of gcc in jammy is 11.4.

  Many NVidia drivers, wifi drivers, VirtualBox (from our Repo), etc
  fail to build the modules, because of a gcc compiler version mismatch
  between what the current running kernel was built by, and the module
  being built.

  I recognized this while helping Users with NVidia driver compile errors on the forum, and came up with this work-around for them:
  https://ubuntuforums.org/showthread.php?t=2494273&p=14175164#post14175164

  Summary:
  Install gcc-12 & g++-12 on 22.04.3 and use it as the compiler.

  Since then, this work-around has helped to resolve problems with
  running the 6.5.0 series kernels and building modules for other
  applications and hardware drivers: VirtualBox, WiFi Drivers, etc. for
  use with the 6.5.0 series.

  I have run this for over a month as my default with no ill affects. I
  have continued to recommend this work-around to many user to solve
  their problems...

  *** I think it is time to look at pushing through gcc-12 as the
  default compiler for 22.04.3 through the normal updates channel.

  ProblemType: Bug
  DistroRelease: Ubuntu 22.04
  Package: gcc 4:11.2.0-1ubuntu1
  ProcVersionSignature: Ubuntu 6.5.0-14.14~22.04.1-generic 6.5.3
  Uname: Linux 6.5.0-14-generic x86_64
  NonfreeKernelModules: zfs nvidia_modeset nvidia
  ApportVersion: 2.20.11-0ubuntu82.5
  Architecture: amd64
  CasperMD5CheckResult: pass
  CloudArchitecture: x86_64
  CloudID: none
  CloudName: none
  CloudPlatform: none
  CloudSubPlatform: config
  CurrentDesktop: GNOME
  Date: Sun Jan 28 08:23:37 2024
  InstallationDate: Installed on 2022-09-19 (496 days ago)
  InstallationMedia: Ubuntu-Server 22.04.1 LTS "Jammy Jellyfish" - Release amd64 (20220809)
  SourcePackage: gcc-defaults
  UpgradeStatus: No upgrade log present (probably fresh install)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/gcc-defaults/+bug/2051457/+subscriptions