Merge ~raharper/curtin:fix/eoan-disable-kernel-img-conf into curtin:master

[Ryan Harper]

curthooks: skip setup_kernel_img_conf on eoan and newer

In Eoan, link_in_boot is the default so curtin no longer needs
to generate a kernel-img.conf controlling link_in_boot.

LP: #1847257

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:2644b90075608bbf42b134e377169e11f1e826f8
https://jenkins.ubuntu.com/server/job/curtin-ci/3741/
Executed test runs:
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-arm64/3741/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-ppc64el/3741/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-s390x/3741/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=torkoal/3741/

Click here to trigger a rebuild:
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review: Approve (continuous-integration)

[Dan Watkins (oddbloke)]

A couple of nits inline, and one question for my own edification. Nothing blocking, though, so +1 and will leave you to land with/without the nits addressed.

review: Approve

029aeeb... by Ryan Harper on 2019-10-18

Compare tuple of integers instead of floats

a76b74e... by Ryan Harper on 2019-10-18

Add bug reference to SkipTest message

[Ryan Harper (raharper)]

Added a comment about curthooks in general.

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:a76b74e64ec7f0536a18b5d4e17fde7f21334575
https://jenkins.ubuntu.com/server/job/curtin-ci/3745/
Executed test runs:
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-arm64/3745/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-ppc64el/3745/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-s390x/3745/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=torkoal/3745/

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/curtin-ci/3745//rebuild

review: Approve (continuous-integration)

diff --git a/curtin/commands/curthooks.py b/curtin/commands/curthooks.py
index 478ce26..edbaddf 100644
--- a/curtin/commands/curthooks.py
+++ b/curtin/commands/curthooks.py
@@ -262,6 +262,11 @@ def get_flash_kernel_pkgs(arch=None, uefi=None):
 
 
 def setup_kernel_img_conf(target):
+    # kernel-img.conf only needed on release prior to 19.10
+    lsb_info = distro.lsb_release(target=target)
+    if tuple(map(int, lsb_info['release'].split('.'))) >= (19, 10):
+        return
+
     kernel_img_conf_vars = {
         'bootloader': 'no',
         'inboot': 'yes',
diff --git a/tests/unittests/test_curthooks.py b/tests/unittests/test_curthooks.py
index 613f068..ceab906 100644
--- a/tests/unittests/test_curthooks.py
+++ b/tests/unittests/test_curthooks.py
@@ -130,6 +130,11 @@ class TestSetupKernelImgConf(CiTestCase):
         self.add_patch('curtin.util.get_architecture', 'mock_arch')
         self.add_patch('curtin.util.write_file', 'mock_write_file')
         self.target = 'not-a-real-target'
+        self.add_patch('curtin.distro.lsb_release', 'mock_lsb_release')
+        self.mock_lsb_release.return_value = {
+            'codename': 'xenial',
+            'release': '16.04',
+        }
 
     def test_on_s390x(self):
         self.mock_machine.return_value = "s390x"
@@ -173,6 +178,20 @@ do_initrd = yes
 link_in_boot = no
 """)
 
+    def test_skips_on_eoan_or_newer(self):
+        test_releases = [('eoan', '19.10'), ('ff', '20.04')]
+        test_params = [
+            ('s390x', 's390x'), ('i686', 'i386'), ('x86_64', 'amd64')]
+        for code, rel in test_releases:
+            self.mock_lsb_release.return_value = {
+                'codename': code, 'release': rel
+            }
+            for machine, arch in test_params:
+                self.mock_machine.return_value = machine
+                self.mock_arch.return_value = arch
+                curthooks.setup_kernel_img_conf(self.target)
+                self.assertEqual(0, self.mock_write_file.call_count)
+
 
 class TestInstallMissingPkgs(CiTestCase):
     def setUp(self):
diff --git a/tests/vmtests/__init__.py b/tests/vmtests/__init__.py
index 3119a40..5a79d13 100644
--- a/tests/vmtests/__init__.py
+++ b/tests/vmtests/__init__.py
@@ -1725,6 +1725,9 @@ class VMBaseClass(TestCase):
         """ Test curtin install kernel-img.conf correctly. """
         if self.target_distro != 'ubuntu':
             raise SkipTest("kernel-img.conf not needed in non-ubuntu releases")
+        if self.target_release not in ['trusty', 'xenial', 'bionic', 'disco']:
+            raise SkipTest(
+                "LP: #1847257 kernel-img.conf not needed in eoan and newer")
         kconf = 'kernel-img.conf'
         self.output_files_exist([kconf])
         if self.target_arch in ['i386', 'amd64']: