support building for a specific kernel version

Slightly rework things so that we can provide a kernel release/version
tag to mkinitfs and have it only operate on that, suffixing all the
relevant files and passing the info on to boot-deploy.

Signed-off-by: Caleb Connolly <caleb@postmarketos.org>

cmd/mkinitfs/main.go

@@ -40,6 +40,7 @@ func main() {
 	defer func() { os.Exit(retCode) }()
 
 	outDir := flag.String("d", "/boot", "Directory to output initfs(-extra) and other boot files")
+	kernVerArg := flag.String("k", "guess", "Kernel version to run for")
 
 	var showVersion bool
 	flag.BoolVar(&showVersion, "version", false, "Print version and quit.")
@@ -48,6 +49,8 @@ func main() {
 	flag.BoolVar(&disableBootDeploy, "no-bootdeploy", false, "Disable running 'boot-deploy' after generating archives.")
 	flag.Parse()
 
+	kernVer := *kernVerArg
+
 	if showVersion {
 		fmt.Printf("%s - %s\n", filepath.Base(os.Args[0]), Version)
 		return
@@ -68,12 +71,15 @@ func main() {
 
 	defer misc.TimeFunc(time.Now(), "mkinitfs")
 
-	kernVer, err := osutil.GetKernelVersion()
+	if kernVer == "guess" {
+		_kernVer, err := osutil.GetKernelVersion()
 		if err != nil {
 			log.Println(err)
 			retCode = 1
 			return
 		}
+		kernVer = _kernVer
+	}
 
 	// temporary working dir
 	workDir, err := os.MkdirTemp("", "mkinitfs")
@@ -111,16 +117,16 @@ func main() {
 		hookfiles.New("/etc/mkinitfs/files"),
 		hookscripts.New("/usr/share/mkinitfs/hooks", "/hooks"),
 		hookscripts.New("/etc/mkinitfs/hooks", "/hooks"),
-		modules.New("/usr/share/mkinitfs/modules"),
+		modules.New("/usr/share/mkinitfs/modules", kernVer),
-		modules.New("/etc/mkinitfs/modules"),
+		modules.New("/etc/mkinitfs/modules", kernVer),
 	})
 	initfsExtra := initramfs.New([]filelist.FileLister{
 		hookfiles.New("/usr/share/mkinitfs/files-extra"),
 		hookfiles.New("/etc/mkinitfs/files-extra"),
 		hookscripts.New("/usr/share/mkinitfs/hooks-extra", "/hooks-extra"),
 		hookscripts.New("/etc/mkinitfs/hooks-extra", "/hooks-extra"),
-		modules.New("/usr/share/mkinitfs/modules-extra"),
+		modules.New("/usr/share/mkinitfs/modules-extra", kernVer),
-		modules.New("/etc/mkinitfs/modules-extra"),
+		modules.New("/etc/mkinitfs/modules-extra", kernVer),
 	})
 
 	if err := initramfsAr.AddItems(initfs); err != nil {
@@ -141,7 +147,7 @@ func main() {
 		}
 	}
 
-	if err := initramfsAr.Write(filepath.Join(workDir, "initramfs"), os.FileMode(0644)); err != nil {
+	if err := initramfsAr.Write(filepath.Join(workDir, fmt.Sprintf("initramfs-%s", kernVer)), os.FileMode(0644)); err != nil {
 		log.Println(err)
 		log.Println("failed to generate: ", "initramfs")
 		retCode = 1
@@ -177,7 +183,7 @@ func main() {
 
 	// Final processing of initramfs / kernel is done by boot-deploy
 	if !disableBootDeploy {
-		if err := bootDeploy(workDir, *outDir, devinfo); err != nil {
+		if err := bootDeploy(workDir, *outDir, devinfo, kernVer); err != nil {
 			log.Println(err)
 			log.Println("boot-deploy failed")
 			retCode = 1
@@ -186,10 +192,10 @@ func main() {
 	}
 }
 
-func bootDeploy(workDir string, outDir string, devinfo deviceinfo.DeviceInfo) error {
+func bootDeploy(workDir string, outDir string, devinfo deviceinfo.DeviceInfo, kernVer string) error {
 	log.Print("== Using boot-deploy to finalize/install files ==")
 	defer misc.TimeFunc(time.Now(), "boot-deploy")
 
-	bd := bootdeploy.New(workDir, outDir, devinfo)
+	bd := bootdeploy.New(workDir, outDir, devinfo, kernVer)
 	return bd.Run()
 }

internal/bootdeploy/bootdeploy.go

@@ -18,6 +18,7 @@ type BootDeploy struct {
 	inDir   string
 	outDir  string
 	devinfo deviceinfo.DeviceInfo
+	kernVer string
 }
 
 // New returns a new BootDeploy, which then runs:
@@ -26,11 +27,12 @@ type BootDeploy struct {
 //
 // devinfo is used to access some deviceinfo values, such as UbootBoardname
 // and GenerateSystemdBoot
-func New(inDir string, outDir string, devinfo deviceinfo.DeviceInfo) *BootDeploy {
+func New(inDir string, outDir string, devinfo deviceinfo.DeviceInfo, kernVer string) *BootDeploy {
 	return &BootDeploy{
 		inDir:   inDir,
 		outDir:  outDir,
 		devinfo: devinfo,
+		kernVer: kernVer,
 	}
 }
 
@@ -43,10 +45,11 @@ func (b *BootDeploy) Run() error {
 		}
 	}
 
-	kernels, err := getKernelPath(b.outDir, b.devinfo.GenerateSystemdBoot == "true")
+	kernels, err := getKernelPath(b.outDir, b.kernVer, b.devinfo.GenerateSystemdBoot == "true")
 	if err != nil {
 		return err
 	}
+	println(fmt.Sprintf("kernels: %v\n", kernels))
 
 	// Pick a kernel that does not have suffixes added by boot-deploy
 	var kernFile string
@@ -79,8 +82,9 @@ func (b *BootDeploy) Run() error {
 
 	// boot-deploy -i initramfs -k vmlinuz-postmarketos-rockchip -d /tmp/cpio -o /tmp/foo initramfs-extra
 	args := []string{
-		"-i", "initramfs",
+		"-i", fmt.Sprintf("initramfs-%s", b.kernVer),
 		"-k", kernFilename,
+		"-v", b.kernVer,
 		"-d", b.inDir,
 		"-o", b.outDir,
 	}
@@ -88,6 +92,7 @@ func (b *BootDeploy) Run() error {
 	if b.devinfo.CreateInitfsExtra {
 		args = append(args, "initramfs-extra")
 	}
+	println(fmt.Sprintf("Calling boot-deply with args: %v\n", args))
 	cmd := exec.Command("boot-deploy", args...)
 
 	cmd.Stdout = os.Stdout
@@ -99,20 +104,20 @@ func (b *BootDeploy) Run() error {
 	return nil
 }
 
-func getKernelPath(outDir string, zboot bool) ([]string, error) {
+func getKernelPath(outDir string, kernVer string, zboot bool) ([]string, error) {
 	var kernels []string
 	if zboot {
-		kernels, _ = filepath.Glob(filepath.Join(outDir, "linux.efi"))
+		kernels, _ = filepath.Glob(filepath.Join(outDir, fmt.Sprintf("linux-%s.efi", kernVer)))
 		if len(kernels) > 0 {
 			return kernels, nil
 		}
 		// else fallback to vmlinuz* below
 	}
 
-	kernFile := "vmlinuz*"
+	kernFile := fmt.Sprintf("vmlinuz-%s", kernVer)
 	kernels, _ = filepath.Glob(filepath.Join(outDir, kernFile))
 	if len(kernels) == 0 {
-		return nil, errors.New("Unable to find any kernels at " + filepath.Join(outDir, kernFile))
+		return nil, errors.New("Unable to find any kernels at " + filepath.Join(outDir, kernFile) + " or " + filepath.Join(outDir, fmt.Sprintf("linux-%s.efi", kernVer)))
 	}
 
 	return kernels, nil

internal/filelist/modules/modules.go

@@ -12,26 +12,22 @@ import (
 
 	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/filelist"
 	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/misc"
-	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/osutil"
 )
 
 type Modules struct {
 	modulesListPath string
+	kernVer         string
 }
 
 // New returns a new Modules that will read in lists of kernel modules in the given path.
-func New(modulesListPath string) *Modules {
+func New(modulesListPath string, kernVer string) *Modules {
 	return &Modules{
 		modulesListPath: modulesListPath,
+		kernVer:         kernVer,
 	}
 }
 
 func (m *Modules) List() (*filelist.FileList, error) {
-	kernVer, err := osutil.GetKernelVersion()
-	if err != nil {
-		return nil, err
-	}
-
 	files := filelist.NewFileList()
 	libDir := "/usr/lib/modules"
 	if exists, err := misc.Exists(libDir); !exists {
@@ -40,7 +36,7 @@ func (m *Modules) List() (*filelist.FileList, error) {
 		return nil, fmt.Errorf("received unexpected error when getting status for %q: %w", libDir, err)
 	}
 
-	modDir := filepath.Join(libDir, kernVer)
+	modDir := filepath.Join(libDir, m.kernVer)
 	if exists, err := misc.Exists(modDir); !exists {
 		// dir /lib/modules/<kernel> if kernel built without module support, so just print a message
 		log.Printf("-- kernel module directory not found: %q, not including modules", modDir)