preflight: Import existing VM from system libvirt connection

This includes:

* Deleting the `crc` VM from system libvirt.
* Ensuring the disk image has the current user as owner.

cmd/crc/cmd/config/config_linux.go

@@ -38,4 +38,6 @@ var (
 	SkipCheckNetworkManagerInstalled = cfg.AddSetting("skip-check-network-manager-installed", nil, []cfg.ValidationFnType{cfg.ValidateBool}, []cfg.SetFn{cfg.SuccessfullyApplied})
 	WarnCheckNetworkManagerRunning   = cfg.AddSetting("warn-check-network-manager-running", nil, []cfg.ValidationFnType{cfg.ValidateBool}, []cfg.SetFn{cfg.SuccessfullyApplied})
 	SkipCheckNetworkManagerRunning   = cfg.AddSetting("skip-check-network-manager-running", nil, []cfg.ValidationFnType{cfg.ValidateBool}, []cfg.SetFn{cfg.SuccessfullyApplied})
+	WarnCheckSystemLibvirtVM         = cfg.AddSetting("warn-check-system-libvirt-vm", nil, []cfg.ValidationFnType{cfg.ValidateBool}, []cfg.SetFn{cfg.SuccessfullyApplied})
+	SkipCheckSystemLibvirtVM         = cfg.AddSetting("skip-check-system-libvirt-vm", nil, []cfg.ValidationFnType{cfg.ValidateBool}, []cfg.SetFn{cfg.SuccessfullyApplied})
 )

pkg/crc/preflight/preflight_checks_linux.go

@@ -547,3 +547,49 @@ func CheckNetworkManagerIsRunning() error {
 func fixNetworkManagerIsRunning() error {
 	return fmt.Errorf("NetworkManager is required. Please make sure it is installed and running manually")
 }
+
+func checkSystemLibvirtVM() error {
+	logging.Debug("Checking for existing VM on libvirt's system connection")
+	stdOut, stdErr, err := crcos.RunWithDefaultLocale("virsh", "--connect", "qemu:///system", "list", "--all")
+	if err != nil {
+		return fmt.Errorf("%+v: %s", err, stdErr)
+	}
+	outputSlice := strings.Split(stdOut, "\n")
+	for _, stdOut = range outputSlice {
+		stdOut = strings.TrimSpace(stdOut)
+		if strings.HasPrefix(stdOut, "crc") {
+			logging.Debug("Found existing VM on libvirt system connection")
+			return errors.New("Existing VM on system libvirt connection")
+		}
+	}
+	return nil
+}
+
+func fixSystemLibvirtVM() error {
+	logging.Debug("Deleting existing VM from libvirt's system connection")
+	_, stdErr, err := crcos.RunWithDefaultLocale("virsh", "--connect", "qemu:///system", "delete", "crc")
+	if err != nil {
+		// VM is probably not running, that's OK.
+		logging.Debug("Failed to stop `crc` VM: %+v: %s", err, stdErr)
+	}
+	_, stdErr, err = crcos.RunWithDefaultLocale("virsh", "--connect", "qemu:///system", "undefine", "crc")
+	if err != nil {
+		return fmt.Errorf("%+v: %s", err, stdErr)
+	}
+
+	// Ensure disk is owned by current user
+
+	// FIXME: First check if owner isn't already correctly set, even though if this function is called, it likely means
+	// it's not.
+	currentUser, err := user.Current()
+	if err != nil {
+		return fmt.Errorf("Error fetching current user info: %+v: %s", err, stdErr)
+	}
+	diskPath := filepath.Join(constants.MachineBaseDir, "machines", constants.DefaultName, constants.DefaultName)
+	err = crcos.ChownAsRoot(currentUser, diskPath)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

pkg/crc/preflight/preflight_linux.go

@@ -115,6 +115,13 @@ var libvirtPreflightChecks = [...]PreflightCheck{
 		fixDescription:   "Writing dnsmasq config for crc",
 		fix:              fixCrcDnsmasqConfigFile,
 	},
+	{
+		configKeySuffix:  "check-system-libvirt-vm",
+		checkDescription: "Checking for existing `crc` VM on system libvirt connection",
+		check:            checkSystemLibvirtVM,
+		fixDescription:   "Importing existing `crc` VM",
+		fix:              fixSystemLibvirtVM,
+	},
 }
 
 func getPreflightChecks() []PreflightCheck {