mantle/kola/testiso: support testing coreos.liveiso.fromram installs

In coreos/fedora-coreos-config#2544 we added
a new `coreos.liveiso.fromram` kernel argument to instruct the ISO
image to boot completely from memory in order to facilitate installs
back to the same disk the ISO was booted from in iso-as-disk mode
(i.e. dd the ISO file to a hard drive or partition on a hard drive).

Let's test here that we can boot completely from memory and that
/run/media/iso is not mounted.

Currently this doesn't actually do an install to the same disk that
we booted from (actually the iso-as-disk tests don't actually do
installs at all, but just verify they can boot), but rather just
verifies the ISO isn't mounted after the live system boots up, which
should be sufficient.

mantle/cmd/kola/testiso.go

@@ -64,6 +64,7 @@ var (
 	enableUefi       bool
 	enableUefiSecure bool
 	isOffline        bool
+	isISOFromRAM     bool
 
 	// The iso-as-disk tests are only supported in x86_64 because other
 	// architectures don't have the required hybrid partition table.
@@ -79,7 +80,7 @@ var (
 		"iso-live-login.4k.uefi",
 		"iso-offline-install.bios",
 		"iso-offline-install.mpath.bios",
-		"iso-offline-install.4k.uefi",
+		"iso-offline-install-fromram.4k.uefi",
 		"miniso-install.bios",
 		"miniso-install.nm.bios",
 		"miniso-install.4k.uefi",
@@ -101,7 +102,7 @@ var (
 	}
 	tests_ppc64le = []string{
 		"iso-live-login.ppcfw",
-		"iso-offline-install.ppcfw",
+		"iso-offline-install-fromram.ppcfw",
 		"iso-offline-install.mpath.ppcfw",
 		"iso-offline-install.4k.ppcfw",
 		"miniso-install.ppcfw",
@@ -114,7 +115,7 @@ var (
 	tests_aarch64 = []string{
 		"iso-live-login.uefi",
 		"iso-live-login.4k.uefi",
-		"iso-offline-install.uefi",
+		"iso-offline-install-fromram.uefi",
 		"iso-offline-install.mpath.uefi",
 		"iso-offline-install.4k.uefi",
 		"miniso-install.uefi",
@@ -130,6 +131,8 @@ var (
 
 const (
 	installTimeout = 10 * time.Minute
+	// https://github.com/coreos/fedora-coreos-config/pull/2544
+	liveISOFromRAMKarg = "coreos.liveiso.fromram"
 )
 
 var liveOKSignal = "live-test-OK"
@@ -236,6 +239,24 @@ RequiredBy=coreos-installer.target
 # for iso-as-disk
 RequiredBy=multi-user.target`
 
+// Unit to check that /run/media/iso is not mounted when
+// coreos.liveiso.fromram kernel argument is passed
+var isoNotMountedUnit = `[Unit]
+Description=Verify ISO is not mounted when coreos.liveiso.fromram
+OnFailure=emergency.target
+OnFailureJobMode=isolate
+ConditionKernelCommandLine=coreos.liveiso.fromram
+[Service]
+Type=oneshot
+StandardOutput=kmsg+console
+StandardError=kmsg+console
+RemainAfterExit=yes
+# Would like to use SuccessExitStatus but it doesn't support what
+# we want: https://github.com/systemd/systemd/issues/10297#issuecomment-1672002635
+ExecStart=bash -c "if mountpoint /run/media/iso 2>/dev/null; then exit 1; fi"
+[Install]
+RequiredBy=coreos-installer.target`
+
 var nmConnectionId = "CoreOS DHCP"
 var nmConnectionFile = "coreos-dhcp.nmconnection"
 var nmConnection = fmt.Sprintf(`[connection]
@@ -519,6 +540,12 @@ func runTestIso(cmd *cobra.Command, args []string) error {
 		if kola.HasString("offline", strings.Split(components[0], "-")) {
 			isOffline = true
 		}
+		// For fromram it is a part of the first component. i.e. for
+		// iso-offline-install-fromram.uefi we need to search for 'fromram' in
+		// iso-offline-install-fromram, which is currently in components[0].
+		if kola.HasString("fromram", strings.Split(components[0], "-")) {
+			isISOFromRAM = true
+		}
 
 		switch components[0] {
 		case "pxe-offline-install", "pxe-online-install":
@@ -527,7 +554,7 @@ func runTestIso(cmd *cobra.Command, args []string) error {
 			duration, err = testAsDisk(ctx, filepath.Join(outputDir, test))
 		case "iso-live-login":
 			duration, err = testLiveLogin(ctx, filepath.Join(outputDir, test))
-		case "iso-install", "iso-offline-install":
+		case "iso-install", "iso-offline-install", "iso-offline-install-fromram":
 			duration, err = testLiveIso(ctx, inst, filepath.Join(outputDir, test), false)
 		case "miniso-install":
 			duration, err = testLiveIso(ctx, inst, filepath.Join(outputDir, test), true)
@@ -711,13 +738,15 @@ func testLiveIso(ctx context.Context, inst platform.Install, outdir string, mini
 		return 0, err
 	}
 
+	var isoKernelArgs []string
 	var keys []string
 	keys = append(keys, strings.TrimSpace(string(sshPubKeyBuf)))
 	virtioJournalConfig.AddAuthorizedKeys("core", keys)
 
 	liveConfig := *virtioJournalConfig
 	liveConfig.AddSystemdUnit("live-signal-ok.service", liveSignalOKUnit, conf.Enable)
 	liveConfig.AddSystemdUnit("verify-no-efi-boot-entry.service", verifyNoEFIBootEntry, conf.Enable)
+	liveConfig.AddSystemdUnit("iso-not-mounted-when-fromram.service", isoNotMountedUnit, conf.Enable)
 	liveConfig.AddSystemdUnit("coreos-test-entered-emergency-target.service", signalFailureUnit, conf.Enable)
 
 	targetConfig := *virtioJournalConfig
@@ -738,7 +767,11 @@ func testLiveIso(ctx context.Context, inst platform.Install, outdir string, mini
 		liveConfig.AddFile(nmstateConfigFile, nmstateConfig, 0644)
 	}
 
-	mach, err := inst.InstallViaISOEmbed(nil, liveConfig, targetConfig, outdir, isOffline, minimal)
+	if isISOFromRAM {
+		isoKernelArgs = append(isoKernelArgs, liveISOFromRAMKarg)
+	}
+
+	mach, err := inst.InstallViaISOEmbed(isoKernelArgs, liveConfig, targetConfig, outdir, isOffline, minimal)
 	if err != nil {
 		return 0, errors.Wrapf(err, "running iso install")
 	}