Build UEFI-only ISO for UEFI boot

This change makes ironic building UEFI-only bootable
ISO image (when being asked to build a UEFI-bootable image)
rather than building a hybrid BIOS/UEFI-bootable ISO.

The motivation behind this change is to make node boot more
predicable in the sense that if the user asks for UEFI boot,
the node would either boot over UEFI or fail.

On top of that, the ISO image slims down a tad bit and syslinux
boot loader presence on the conductor machine is not a
requirement any more.

Change-Id: If7828f72724cc7532f97cab758a29a9e8345850e
Story: 1526753
Task: 28368

ironic/common/images.py

@@ -243,17 +243,12 @@ def create_isolinux_image_for_uefi(output_file, deploy_iso, kernel, ramdisk,
     :raises: ImageCreationFailed, if image creation failed while copying files
         or while running command to generate iso.
     """
-    ISOLINUX_BIN = 'isolinux/isolinux.bin'
-    ISOLINUX_CFG = 'isolinux/isolinux.cfg'
-
-    isolinux_options = {'kernel': '/vmlinuz', 'ramdisk': '/initrd'}
     grub_options = {'linux': '/vmlinuz', 'initrd': '/initrd'}
 
     with utils.tempdir() as tmpdir:
         files_info = {
             kernel: 'vmlinuz',
             ramdisk: 'initrd',
-            CONF.isolinux_bin: ISOLINUX_BIN,
         }
 
         # Open the deploy iso used to initiate deploy and copy the
@@ -274,12 +269,6 @@ def create_isolinux_image_for_uefi(output_file, deploy_iso, kernel, ramdisk,
             finally:
                 _umount_without_raise(mountdir)
 
-        cfg = _generate_cfg(kernel_params,
-                            CONF.isolinux_config_template, isolinux_options)
-
-        isolinux_cfg = os.path.join(tmpdir, ISOLINUX_CFG)
-        utils.write_to_file(isolinux_cfg, cfg)
-
         # Generate and copy grub config file.
         grub_cfg = os.path.join(tmpdir, grub_rel_path)
         grub_conf = _generate_cfg(kernel_params,
@@ -288,12 +277,10 @@ def create_isolinux_image_for_uefi(output_file, deploy_iso, kernel, ramdisk,
 
         # Create the boot_iso.
         try:
-            utils.execute('mkisofs', '-r', '-V', "VMEDIA_BOOT_ISO",
+            utils.execute('mkisofs', '-r', '-V', "VMEDIA_BOOT_ISO", '-l',
-                          '-cache-inodes', '-J', '-l', '-no-emul-boot',
-                          '-boot-load-size', '4', '-boot-info-table',
-                          '-b', ISOLINUX_BIN, '-eltorito-alt-boot',
                           '-e', e_img_rel_path, '-no-emul-boot',
                           '-o', output_file, tmpdir)
+
         except processutils.ProcessExecutionError as e:
             LOG.exception("Creating ISO image failed.")
             raise exception.ImageCreationFailed(image_type='iso', error=e)

ironic/tests/unit/common/test_images.py

@@ -496,19 +496,14 @@ class FsImageTestCase(base.TestCase):
         files_info = {
             'path/to/kernel': 'vmlinuz',
             'path/to/ramdisk': 'initrd',
-            CONF.isolinux_bin: 'isolinux/isolinux.bin',
             'path/to/grub': 'relpath/to/grub.cfg',
             'sourceabspath/to/efiboot.img': 'path/to/efiboot.img'
         }
-        cfg = "cfg"
-        cfg_file = 'tmpdir/isolinux/isolinux.cfg'
         grubcfg = "grubcfg"
         grub_file = 'tmpdir/relpath/to/grub.cfg'
-        gen_cfg_mock.side_effect = cfg, grubcfg
+        gen_cfg_mock.side_effect = (grubcfg,)
 
         params = ['a=b', 'c']
-        isolinux_options = {'kernel': '/vmlinuz',
-                            'ramdisk': '/initrd'}
         grub_options = {'linux': '/vmlinuz',
                         'initrd': '/initrd'}
 
@@ -531,18 +526,12 @@ class FsImageTestCase(base.TestCase):
                                               kernel_params=params)
         mount_mock.assert_called_once_with('path/to/deploy_iso', 'mountdir')
         create_root_fs_mock.assert_called_once_with('tmpdir', files_info)
-        gen_cfg_mock.assert_any_call(params, CONF.isolinux_config_template,
-                                     isolinux_options)
-        write_to_file_mock.assert_any_call(cfg_file, cfg)
         gen_cfg_mock.assert_any_call(params, CONF.grub_config_template,
                                      grub_options)
         write_to_file_mock.assert_any_call(grub_file, grubcfg)
         execute_mock.assert_called_once_with(
-            'mkisofs', '-r', '-V', "VMEDIA_BOOT_ISO", '-cache-inodes', '-J',
+            'mkisofs', '-r', '-V', 'VMEDIA_BOOT_ISO', '-l', '-e',
-            '-l', '-no-emul-boot', '-boot-load-size', '4', '-boot-info-table',
+            'path/to/efiboot.img', '-no-emul-boot', '-o', 'tgt_file', 'tmpdir')
-            '-b', 'isolinux/isolinux.bin', '-eltorito-alt-boot',
-            '-e', 'path/to/efiboot.img', '-no-emul-boot',
-            '-o', 'tgt_file', 'tmpdir')
         umount_mock.assert_called_once_with('mountdir')
 
     @mock.patch.object(images, '_create_root_fs', autospec=True)

releasenotes/notes/build-uefi-only-iso-ce6bcb0da578d1d6.yaml

@@ -0,0 +1,7 @@
+---
+other:
+  - |
+    The Bare Metal service now builds UEFI-only bootable ISO image (when being asked to
+    build a UEFI-bootable image) rather than building a hybrid
+    BIOS/UEFI-bootable ISO.
+