nixpkgs/nixos/modules/system/boot/kexec.nix
2021-04-02 19:20:23 +08:00

33 lines
1.1 KiB
Nix

{ pkgs, lib, ... }:
{
config = lib.mkIf (lib.meta.availableOn pkgs.stdenv.hostPlatform pkgs.kexectools) {
environment.systemPackages = [ pkgs.kexectools ];
systemd.services.prepare-kexec =
{ description = "Preparation for kexec";
wantedBy = [ "kexec.target" ];
before = [ "systemd-kexec.service" ];
unitConfig.DefaultDependencies = false;
serviceConfig.Type = "oneshot";
path = [ pkgs.kexectools ];
script =
''
# Don't load the current system profile if we already have a kernel loaded
if [[ 1 = "$(</sys/kernel/kexec_loaded)" ]] ; then
echo "kexec kernel has already been loaded, prepare-kexec skipped"
exit 0
fi
p=$(readlink -f /nix/var/nix/profiles/system)
if ! [[ -d $p ]]; then
echo "Could not find system profile for prepare-kexec"
exit 1
fi
echo "Loading NixOS system via kexec."
exec kexec --load $p/kernel --initrd=$p/initrd --append="$(cat $p/kernel-params) init=$p/init"
'';
};
};
}