vz: change linuxBootLoader() to return error, then explicitly ignores the error on caller.

Signed-off-by: Norio Nomura <norio.nomura@gmail.com>

vz: add comment to `bootLoader()`

Signed-off-by: Norio Nomura <norio.nomura@gmail.com>

Author: norio-nomura

pkg/vz/vm_darwin.go

@@ -682,8 +682,9 @@ func getMachineIdentifier(driver *driver.BaseDriver) (*vz.GenericMachineIdentifi
 }
 
 func bootLoader(driver *driver.BaseDriver) (vz.BootLoader, error) {
-	if linuxBootLoder, err := linuxBootLoader(driver); linuxBootLoder != nil {
-		return linuxBootLoder, err
+	// ignore the error it might be a non-existing kernel file
+	if linuxBootLoder, _ := linuxBootLoader(driver); linuxBootLoder != nil {
+		return linuxBootLoder, nil
 	}
 
 	efiVariableStore, err := getEFI(driver)
@@ -700,7 +701,7 @@ func linuxBootLoader(driver *driver.BaseDriver) (*vz.LinuxBootLoader, error) {
 	initrd := filepath.Join(driver.Instance.Dir, filenames.Initrd)
 	if _, err := os.Stat(kernel); err != nil {
 		logrus.Debugf("Kernel file %q not found", kernel)
-		return nil, nil
+		return nil, err
 	}
 	var opt []vz.LinuxBootLoaderOption
 	if b, err := os.ReadFile(kernelCmdline); err == nil {