Key remapping with udev always requires `sudo systemd-hwdb update && sudo udevadm trigger` after reboot

[kachick]

https://github.com/kachick/dotfiles/issues/784 https://github.com/kachick/dotfiles/pull/786

:cry:

[kachick]

https://wiki.archlinux.jp/index.php/%E3%82%B9%E3%82%AD%E3%83%A3%E3%83%B3%E3%82%B3%E3%83%BC%E3%83%89%E3%82%92%E3%82%AD%E3%83%BC%E3%82%B3%E3%83%BC%E3%83%89%E3%81%AB%E3%83%9E%E3%83%83%E3%83%97

systemd-hwdb-update.service の ConditionNeedsUpdate をコメントアウトすると再起動するたびに自動的に更新されます:

[kachick]

https://github.com/NixOS/nixpkgs/blob/cf60e052431bb7289638e08bbf271eae2f8694dc/nixos/modules/system/boot/systemd.nix#L61-L62

[kachick]

https://github.com/NixOS/nixpkgs/blob/cf60e052431bb7289638e08bbf271eae2f8694dc/nixos/modules/services/hardware/udev.nix#L142-L162

[kachick]

https://github.com/NixOS/nixpkgs/blob/9133b9f5554437083a6618581eeae88c53593b0d/nixos/modules/system/boot/systemd/sysusers.nix#L120-L122

      services.systemd-sysusers = {
        # Enable switch-to-configuration to restart the service.
        unitConfig.ConditionNeedsUpdate = [ "" ];

[kachick]

https://github.com/NixOS/nixpkgs/blob/9133b9f5554437083a6618581eeae88c53593b0d/nixos/doc/manual/release-notes/rl-2305.section.md?plain=1#L268 https://github.com/systemd/systemd/pull/25714 https://github.com/NixOS/nixpkgs/blob/9133b9f5554437083a6618581eeae88c53593b0d/nixos/modules/services/hardware/udev.nix#L158

  hwdbBin = pkgs.runCommand "hwdb.bin"
    { preferLocalBuild = true;
      allowSubstitutes = false;
      packages = lib.unique (map toString ([udev] ++ cfg.packages));
    }
    ''
      mkdir -p etc/udev/hwdb.d
      for i in $packages; do
        echo "Adding hwdb files for package $i"
        for j in $i/{etc,lib}/udev/hwdb.d/*; do
          ln -s $j etc/udev/hwdb.d/$(basename $j)
        done
      done

      echo "Generating hwdb database..."
      # hwdb --update doesn't return error code even on errors!
      res="$(${pkgs.buildPackages.systemd}/bin/systemd-hwdb --root=$(pwd) update 2>&1)"
      echo "$res"
      [ -z "$(echo "$res" | egrep '^Error')" ]
      mv etc/udev/hwdb.bin $out
    '';

[kachick]

https://github.com/NixOS/nixpkgs/issues/308937 :eyes:

[kachick]

dotfiles main(0be7fe5)  direnv loaded/allowed via 🐹 v1.22.6 1m26s via ❄️  impure (nix-shell-env) zsh 
> lat /etc/udev
0755 - 10-02 03:33 /etc/udev
0777 - 10-02 03:33 ├── rules.d -> /etc/static/udev/rules.d
0755 - 10-02 03:33 ├── hwdb.d
0777 - 10-02 03:33 │  ├── 98-keyboards.hwdb -> /etc/static/udev/hwdb.d/98-keyboards.hwdb
0777 - 10-02 03:33 │  └── 99-local.hwdb -> /etc/static/udev/hwdb.d/99-local.hwdb
0777 - 10-02 03:33 └── hwdb.bin -> /etc/static/udev/hwdb.bin

dotfiles main(0be7fe5)  direnv loaded/allowed via 🐹 v1.22.6 via ❄️  impure (nix-shell-env) zsh 
> sudo systemd-hwdb update && sudo udevadm trigger

dotfiles main(0be7fe5)  direnv loaded/allowed via 🐹 v1.22.6 via ❄️  impure (nix-shell-env) zsh 
> lat /etc/udev                            
0755   - 10-02 03:35 /etc/udev
0777   - 10-02 03:33 ├── rules.d -> /etc/static/udev/rules.d
0755   - 10-02 03:33 ├── hwdb.d
0777   - 10-02 03:33 │  ├── 98-keyboards.hwdb -> /etc/static/udev/hwdb.d/98-keyboards.hwdb
0777   - 10-02 03:33 │  └── 99-local.hwdb -> /etc/static/udev/hwdb.d/99-local.hwdb
0444 13M 10-02 03:35 └── hwdb.bin

systemd-hwdb update is actually replacing the symlink with binary.

The generated symlink by NixOS is not correct?

[kachick]

Once applied with sudo systemd-hwdb update && sudo udevadm trigger and sudo reboot now. the hwdb.bin will back to symlink. However in the state, it continue to work even thorough reboot again. So just adding the step after nixos-rebuild switch is enough for workaround. :thinking:

[kachick]

This problem looks still exists...

sudo reboot now. the hwdb.bin will back to symlink. However in the state, it continue to work even thorough reboot again.

Looks wrong

[kachick]

https://discourse.nixos.org/t/services-udev-extrahwdb-not-updating-99-local-rules/50849