Merge pull request #990 from alicefr/s390x

s390x: add support for s390x

arch/s390x-options.mk

@@ -0,0 +1,12 @@
+# Copyright (c) 2018 IBM
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+# s390x settings
+
+MACHINETYPE := s390-ccw-virtio
+KERNELPARAMS :=
+MACHINEACCELERATORS :=
+
+QEMUCMD := qemu-system-s390x

cli/kata-check_data_s390x_test.go

@@ -0,0 +1,21 @@
+// Copyright (c) 2018 IBM
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package main
+
+const testCPUInfoTemplate = `
+vendor_id       : IBM/S390
+# processors    : 4
+bogomips per cpu: 20325.00
+max thread id   : 0
+features	: esan3 zarch stfle msa ldisp eimm dfp edat etf3eh highgprs te vx sie 
+cache0          : level=1 type=Data scope=Private size=128K line_size=256 associativity=8
+cache1          : level=1 type=Instruction scope=Private size=96K line_size=256 associativity=6
+cache2          : level=2 type=Data scope=Private size=2048K line_size=256 associativity=8
+cache3          : level=2 type=Instruction scope=Private size=2048K line_size=256 associativity=8
+cache4          : level=3 type=Unified scope=Shared size=65536K line_size=256 associativity=16
+cache5          : level=4 type=Unified scope=Shared size=491520K line_size=256 associativity=30
+processor 0: version = FF,  identification = FFFFFF,  machine = 2964
+`

cli/kata-check_s390x.go

@@ -0,0 +1,124 @@
+// Copyright (c) 2018 Intel Corporation
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package main
+
+import (
+	"fmt"
+	"github.com/sirupsen/logrus"
+	"strings"
+)
+
+const (
+	cpuFlagsTag        = genericCPUFlagsTag
+	archCPUVendorField = genericCPUVendorField
+	// On s390x the cpu model is indicated by the field machine.
+	// Example:
+	// processor 0: version = FF,  identification = 3FEC87,  machine = 2964
+	archCPUModelField = "machine"
+)
+
+// archRequiredCPUFlags maps a CPU flag value to search for and a
+// human-readable description of that value.
+var archRequiredCPUFlags = map[string]string{}
+
+// archRequiredCPUAttribs maps a CPU (non-CPU flag) attribute value to search for
+// and a human-readable description of that value.
+var archRequiredCPUAttribs = map[string]string{}
+
+// archRequiredKernelModules maps a required module name to a human-readable
+// description of the modules functionality and an optional list of
+// required module parameters.
+var archRequiredKernelModules = map[string]kernelModule{
+	"kvm": {
+		desc: "Kernel-based Virtual Machine",
+	},
+}
+
+func setCPUtype() error {
+	return nil
+}
+
+// kvmIsUsable determines if it will be possible to create a full virtual machine
+// by creating a minimal VM and then deleting it.
+func kvmIsUsable() error {
+	return genericKvmIsUsable()
+}
+
+func archHostCanCreateVMContainer() error {
+	return kvmIsUsable()
+}
+
+// hostIsVMContainerCapable checks to see if the host is theoretically capable
+// of creating a VM container.
+func hostIsVMContainerCapable(details vmContainerCapableDetails) error {
+
+	_, err := getCPUInfo(details.cpuInfoFile)
+	if err != nil {
+		return err
+	}
+
+	count, err := checkKernelModules(details.requiredKernelModules, archKernelParamHandler)
+	if err != nil {
+		return err
+	}
+
+	if count == 0 {
+		return nil
+	}
+
+	return fmt.Errorf("ERROR: %s", failMessage)
+
+}
+
+func archKernelParamHandler(onVMM bool, fields logrus.Fields, msg string) bool {
+	return genericArchKernelParamHandler(onVMM, fields, msg)
+}
+
+// getS390xCPUDetails returns the cpu information
+func getS390xCPUDetails() (vendor, model string, err error) {
+	prefixModel := "processor"
+	cpuinfo, err := getCPUInfo(procCPUInfo)
+	if err != nil {
+		return "", "", err
+	}
+
+	lines := strings.Split(cpuinfo, "\n")
+
+	for _, line := range lines {
+		if archCPUVendorField != "" {
+			if strings.HasPrefix(line, archCPUVendorField) {
+				fields := strings.Split(line, ":")
+				if len(fields) > 1 {
+					vendor = strings.TrimSpace(fields[1])
+				}
+			}
+		}
+		if archCPUModelField != "" {
+			if strings.HasPrefix(line, prefixModel) {
+				fields := strings.Split(strings.TrimSpace(line), ",")
+				cpuModel := strings.Split(fields[2], "=")
+				model = strings.TrimSpace(cpuModel[1])
+			}
+		}
+	}
+
+	if vendor == "" {
+		return "", "", fmt.Errorf("cannot find vendor field in file %v", procCPUInfo)
+	}
+
+	if model == "" {
+		return "", "", fmt.Errorf("Error in parsing cpu model from %v", procCPUInfo)
+	}
+
+	return vendor, model, nil
+}
+
+func getCPUDetails() (vendor, model string, err error) {
+	if vendor, model, err := genericGetCPUDetails(); err == nil {
+		return vendor, model, nil
+	}
+	return getS390xCPUDetails()
+}

cli/kata-check_s390x_test.go

@@ -0,0 +1,247 @@
+// Copyright (c) 2018 IBM
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"path/filepath"
+	"testing"
+
+	"github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/assert"
+	"github.com/urfave/cli"
+)
+
+func setupCheckHostIsVMContainerCapable(assert *assert.Assertions, cpuInfoFile string, cpuData []testCPUData, moduleData []testModuleData) {
+	createModules(assert, cpuInfoFile, moduleData)
+
+	// all the modules files have now been created, so deal with the
+	// cpuinfo data.
+	for _, d := range cpuData {
+		err := makeCPUInfoFile(cpuInfoFile, d.vendorID, d.flags)
+		assert.NoError(err)
+
+		details := vmContainerCapableDetails{
+			cpuInfoFile:           cpuInfoFile,
+			requiredCPUFlags:      archRequiredCPUFlags,
+			requiredCPUAttribs:    archRequiredCPUAttribs,
+			requiredKernelModules: archRequiredKernelModules,
+		}
+
+		err = hostIsVMContainerCapable(details)
+		if d.expectError {
+			assert.Error(err)
+		} else {
+			assert.NoError(err)
+		}
+	}
+}
+
+func TestCCCheckCLIFunction(t *testing.T) {
+	assert := assert.New(t)
+
+	dir, err := ioutil.TempDir("", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+
+	savedSysModuleDir := sysModuleDir
+	savedProcCPUInfo := procCPUInfo
+
+	cpuInfoFile := filepath.Join(dir, "cpuinfo")
+
+	// XXX: override
+	sysModuleDir = filepath.Join(dir, "sys/module")
+	procCPUInfo = cpuInfoFile
+
+	defer func() {
+		sysModuleDir = savedSysModuleDir
+		procCPUInfo = savedProcCPUInfo
+	}()
+
+	err = os.MkdirAll(sysModuleDir, testDirMode)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	cpuData := []testCPUData{
+		{"", "", false},
+	}
+
+	moduleData := []testModuleData{
+		{filepath.Join(sysModuleDir, "kvm"), false, "Y"},
+	}
+
+	devNull, err := os.OpenFile(os.DevNull, os.O_WRONLY, 0666)
+	assert.NoError(err)
+	defer devNull.Close()
+
+	savedLogOutput := kataLog.Logger.Out
+
+	// discard normal output
+	kataLog.Logger.Out = devNull
+
+	defer func() {
+		kataLog.Logger.Out = savedLogOutput
+	}()
+
+	setupCheckHostIsVMContainerCapable(assert, cpuInfoFile, cpuData, moduleData)
+
+	ctx := createCLIContext(nil)
+	ctx.App.Name = "foo"
+
+	// create buffer to save logger output
+	buf := &bytes.Buffer{}
+
+	// capture output this time
+	kataLog.Logger.Out = buf
+
+	fn, ok := kataCheckCLICommand.Action.(func(context *cli.Context) error)
+	assert.True(ok)
+
+	err = fn(ctx)
+	assert.NoError(err)
+
+	output := buf.String()
+
+	for _, m := range moduleData {
+		name := path.Base(m.path)
+		assert.True(findAnchoredString(output, name))
+	}
+}
+
+func TestArchKernelParamHandler(t *testing.T) {
+	assert := assert.New(t)
+
+	type testData struct {
+		onVMM        bool
+		fields       logrus.Fields
+		msg          string
+		expectIgnore bool
+	}
+
+	data := []testData{
+		{true, logrus.Fields{}, "", false},
+		{false, logrus.Fields{}, "", false},
+
+		{
+			false,
+			logrus.Fields{
+				// wrong type
+				"parameter": 123,
+			},
+			"foo",
+			false,
+		},
+
+		{
+			false,
+			logrus.Fields{
+				"parameter": "unrestricted_guest",
+			},
+			"",
+			false,
+		},
+
+		{
+			true,
+			logrus.Fields{
+				"parameter": "unrestricted_guest",
+			},
+			"",
+			true,
+		},
+
+		{
+			false,
+			logrus.Fields{
+				"parameter": "nested",
+			},
+			"",
+			true,
+		},
+	}
+
+	for i, d := range data {
+		result := archKernelParamHandler(d.onVMM, d.fields, d.msg)
+		if d.expectIgnore {
+			assert.True(result, "test %d (%+v)", i, d)
+		} else {
+			assert.False(result, "test %d (%+v)", i, d)
+		}
+	}
+}
+
+func TestKvmIsUsable(t *testing.T) {
+	assert := assert.New(t)
+
+	dir, err := ioutil.TempDir("", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+
+	savedKvmDevice := kvmDevice
+	fakeKVMDevice := filepath.Join(dir, "kvm")
+	kvmDevice = fakeKVMDevice
+
+	defer func() {
+		kvmDevice = savedKvmDevice
+	}()
+
+	err = kvmIsUsable()
+	assert.Error(err)
+
+	err = createEmptyFile(fakeKVMDevice)
+	assert.NoError(err)
+
+	err = kvmIsUsable()
+	assert.Error(err)
+}
+
+type TestDataa struct {
+	contents       string
+	expectedVendor string
+	expectedModel  string
+	expectError    bool
+}
+
+func TestGetCPUDetails(t *testing.T) {
+	type testData struct {
+		contents       string
+		expectedVendor string
+		expectedModel  string
+		expectError    bool
+	}
+
+	const validVendorName = "a vendor"
+	validVendor := fmt.Sprintf(`%s  : %s`, archCPUVendorField, validVendorName)
+
+	const validModelName = "some CPU model"
+	validModel := fmt.Sprintf(`processor 0: version = 00,  identification = XXXXX, %s = %s`, archCPUModelField, validModelName)
+
+	validContents := fmt.Sprintf(`
+a       : b
+%s
+foo     : bar
+%s
+`, validVendor, validModel)
+
+	data := []TestDataa{
+		{"", "", "", true},
+		{"invalid", "", "", true},
+		{archCPUVendorField, "", "", true},
+		{validVendor, "", "", true},
+		{validModel, "", "", true},
+		{validContents, validVendorName, validModelName, false},
+	}
+	genericTestGetCPUDetails(t, validVendor, validModel, validContents, data)
+}

cli/kata-env_s390x_test.go

@@ -0,0 +1,91 @@
+// Copyright (c) 2018 IBM
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package main
+
+import (
+	"fmt"
+	vcUtils "github.com/kata-containers/runtime/virtcontainers/utils"
+	"path/filepath"
+	goruntime "runtime"
+)
+
+func getExpectedHostDetails(tmpdir string) (HostInfo, error) {
+	type filesToCreate struct {
+		file     string
+		contents string
+	}
+
+	const expectedKernelVersion = "99.1"
+	const expectedArch = goruntime.GOARCH
+
+	expectedDistro := DistroInfo{
+		Name:    "Foo",
+		Version: "42",
+	}
+
+	expectedCPU := CPUInfo{
+		Vendor: "moi",
+		Model:  "awesome XI",
+	}
+
+	expectedHostDetails := HostInfo{
+		Kernel:             expectedKernelVersion,
+		Architecture:       expectedArch,
+		Distro:             expectedDistro,
+		CPU:                expectedCPU,
+		VMContainerCapable: true,
+		SupportVSocks:      vcUtils.SupportsVsocks(),
+	}
+
+	testProcCPUInfo := filepath.Join(tmpdir, "cpuinfo")
+	testOSRelease := filepath.Join(tmpdir, "os-release")
+
+	// XXX: This file is *NOT* created by this function on purpose
+	// (to ensure the only file checked by the tests is
+	// testOSRelease). osReleaseClr handling is tested in
+	// utils_test.go.
+	testOSReleaseClr := filepath.Join(tmpdir, "os-release-clr")
+
+	testProcVersion := filepath.Join(tmpdir, "proc-version")
+
+	// override
+	procVersion = testProcVersion
+	osRelease = testOSRelease
+	osReleaseClr = testOSReleaseClr
+	procCPUInfo = testProcCPUInfo
+
+	procVersionContents := fmt.Sprintf("Linux version %s a b c",
+		expectedKernelVersion)
+
+	osReleaseContents := fmt.Sprintf(`
+NAME="%s"
+VERSION_ID="%s"
+`, expectedDistro.Name, expectedDistro.Version)
+
+	procCPUInfoContents := fmt.Sprintf(`
+%s	: %s
+processor 0: version = 00,  identification = 3929E7,  %s = %s
+`,
+		archCPUVendorField,
+		expectedCPU.Vendor,
+		archCPUModelField,
+		expectedCPU.Model)
+
+	data := []filesToCreate{
+		{procVersion, procVersionContents},
+		{osRelease, osReleaseContents},
+		{procCPUInfo, procCPUInfoContents},
+	}
+
+	for _, d := range data {
+		err := createFile(d.file, d.contents)
+		if err != nil {
+			return HostInfo{}, err
+		}
+	}
+
+	return expectedHostDetails, nil
+}

cli/utils_s390x.go

@@ -0,0 +1,10 @@
+// Copyright (c) 2018 IBM
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package main
+
+func archConvertStatFs(cgroupFsType int) uint32 {
+	return uint32(cgroupFsType)
+}

versions.yaml

@@ -97,6 +97,9 @@ assets:
       ppc64le:
         name: "centos"
         version: "latest"
+      s390x:
+        name: "ubuntu"
+        version: "latest"
       x86_64:
         name: &default-image-name "clearlinux"
         version: "20640"
@@ -115,6 +118,9 @@ assets:
       ppc64le:
         name: *default-initrd-name
         version: *default-initrd-version
+      s390x:
+        name: *default-initrd-name
+        version: *default-initrd-version
       x86_64:
         name: *default-initrd-name
         version: *default-initrd-version

virtcontainers/hypervisor.go

@@ -525,7 +525,7 @@ func getHostMemorySizeKb(memInfoPath string) (uint64, error) {
 
 // RunningOnVMM checks if the system is running inside a VM.
 func RunningOnVMM(cpuInfoPath string) (bool, error) {
-	if runtime.GOARCH == "arm64" || runtime.GOARCH == "ppc64le" {
+	if runtime.GOARCH == "arm64" || runtime.GOARCH == "ppc64le" || runtime.GOARCH == "s390x" {
 		virtLog.Info("Unable to know if the system is running inside a VM")
 		return false, nil
 	}

virtcontainers/qemu.go

@@ -872,18 +872,20 @@ func (q *qemu) hotplugNetDevice(endpoint Endpoint, op operation) error {
 		return err
 	}
 	var tap TapInterface
+	devID := "virtio-" + tap.ID
+
+	switch endpoint.Type() {
+	case VethEndpointType:
+		drive := endpoint.(*VethEndpoint)
+		tap = drive.NetPair.TapInterface
+	case TapEndpointType:
+		drive := endpoint.(*TapEndpoint)
+		tap = drive.TapInterface
+	default:
+		return fmt.Errorf("this endpoint is not supported")
+	}
 
 	if op == addDevice {
-		switch endpoint.Type() {
-		case VethEndpointType:
-			drive := endpoint.(*VethEndpoint)
-			tap = drive.NetPair.TapInterface
-		case TapEndpointType:
-			drive := endpoint.(*TapEndpoint)
-			tap = drive.TapInterface
-		default:
-			return fmt.Errorf("this endpoint is not supported")
-		}
 
 		if err = q.hotAddNetDevice(tap.Name, endpoint.HardwareAddr(), tap.VMFds, tap.VhostFds); err != nil {
 			return err
@@ -896,34 +898,28 @@ func (q *qemu) hotplugNetDevice(endpoint Endpoint, op operation) error {
 		pciAddr := fmt.Sprintf("%02x/%s", bridge.Addr, addr)
 		endpoint.SetPciAddr(pciAddr)
 
-		devID := "virtio-" + tap.ID
-		if err = q.qmpMonitorCh.qmp.ExecuteNetPCIDeviceAdd(q.qmpMonitorCh.ctx, tap.Name, devID, endpoint.HardwareAddr(), addr, bridge.ID, romFile, int(q.config.NumVCPUs), q.arch.runNested()); err != nil {
+		var machine govmmQemu.Machine
+		machine, err = q.getQemuMachine()
+		if err != nil {
 			return err
 		}
-	} else {
-		switch endpoint.Type() {
-		case VethEndpointType:
-			drive := endpoint.(*VethEndpoint)
-			tap = drive.NetPair.TapInterface
-		case TapEndpointType:
-			drive := endpoint.(*TapEndpoint)
-			tap = drive.TapInterface
-		default:
-			return fmt.Errorf("this endpoint is not supported")
-		}
-
-		if err := q.removeDeviceFromBridge(tap.ID); err != nil {
-			return err
-		}
-
-		devID := "virtio-" + tap.ID
-		if err := q.qmpMonitorCh.qmp.ExecuteDeviceDel(q.qmpMonitorCh.ctx, devID); err != nil {
-			return err
-		}
-		if err := q.qmpMonitorCh.qmp.ExecuteNetdevDel(q.qmpMonitorCh.ctx, tap.Name); err != nil {
-			return err
+		if machine.Type == QemuCCWVirtio {
+			return q.qmpMonitorCh.qmp.ExecuteNetCCWDeviceAdd(q.qmpMonitorCh.ctx, tap.Name, devID, endpoint.HardwareAddr(), addr, bridge.ID, int(q.config.NumVCPUs))
 		}
+		return q.qmpMonitorCh.qmp.ExecuteNetPCIDeviceAdd(q.qmpMonitorCh.ctx, tap.Name, devID, endpoint.HardwareAddr(), addr, bridge.ID, romFile, int(q.config.NumVCPUs), q.arch.runNested())
 	}
+
+	if err := q.removeDeviceFromBridge(tap.ID); err != nil {
+		return err
+	}
+
+	if err := q.qmpMonitorCh.qmp.ExecuteDeviceDel(q.qmpMonitorCh.ctx, devID); err != nil {
+		return err
+	}
+	if err := q.qmpMonitorCh.qmp.ExecuteNetdevDel(q.qmpMonitorCh.ctx, tap.Name); err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -1149,6 +1145,7 @@ func (q *qemu) resumeSandbox() error {
 
 // addDevice will add extra devices to Qemu command line.
 func (q *qemu) addDevice(devInfo interface{}, devType deviceType) error {
+	var err error
 	span, _ := q.trace("addDevice")
 	defer span.Finish()
 
@@ -1165,14 +1162,14 @@ func (q *qemu) addDevice(devInfo interface{}, devType deviceType) error {
 	case config.BlockDrive:
 		q.qemuConfig.Devices = q.arch.appendBlockDevice(q.qemuConfig.Devices, v)
 	case config.VhostUserDeviceAttrs:
-		q.qemuConfig.Devices = q.arch.appendVhostUserDevice(q.qemuConfig.Devices, v)
+		q.qemuConfig.Devices, err = q.arch.appendVhostUserDevice(q.qemuConfig.Devices, v)
 	case config.VFIODev:
 		q.qemuConfig.Devices = q.arch.appendVFIODevice(q.qemuConfig.Devices, v)
 	default:
 		break
 	}
 
-	return nil
+	return err
 }
 
 // getSandboxConsole builds the path of the console where we can read
@@ -1293,6 +1290,8 @@ func genericBridges(number uint32, machineType string) []Bridge {
 		bt = pcieBridge
 	case QemuPseries:
 		bt = pciBridge
+	case QemuCCWVirtio:
+		bt = pciBridge
 	default:
 		return nil
 	}

virtcontainers/qemu_arch_base.go

@@ -86,7 +86,7 @@ type qemuArch interface {
 	appendBlockDevice(devices []govmmQemu.Device, drive config.BlockDrive) []govmmQemu.Device
 
 	// appendVhostUserDevice appends a vhost user device to devices
-	appendVhostUserDevice(devices []govmmQemu.Device, drive config.VhostUserDeviceAttrs) []govmmQemu.Device
+	appendVhostUserDevice(devices []govmmQemu.Device, drive config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error)
 
 	// appendVFIODevice appends a VFIO device to devices
 	appendVFIODevice(devices []govmmQemu.Device, vfioDevice config.VFIODev) []govmmQemu.Device
@@ -151,6 +151,9 @@ const (
 
 	// QemuPseries is a QEMU virt machine type for ppc64le
 	QemuPseries = "pseries"
+
+	// QemuCCWVirtio is a QEMU virt machine type for for s390x
+	QemuCCWVirtio = "s390-ccw-virtio"
 )
 
 // kernelParamsNonDebug is a list of the default kernel
@@ -456,7 +459,7 @@ func (q *qemuArchBase) appendNetwork(devices []govmmQemu.Device, endpoint Endpoi
 		devices = append(devices,
 			govmmQemu.NetDevice{
 				Type:          networkModelToQemuType(netPair.NetInterworkingModel),
-				Driver:        govmmQemu.VirtioNetPCI,
+				Driver:        govmmQemu.VirtioNet,
 				ID:            fmt.Sprintf("network-%d", q.networkIndex),
 				IFName:        netPair.TAPIface.Name,
 				MACAddress:    netPair.TAPIface.HardAddr,
@@ -473,7 +476,7 @@ func (q *qemuArchBase) appendNetwork(devices []govmmQemu.Device, endpoint Endpoi
 		devices = append(devices,
 			govmmQemu.NetDevice{
 				Type:          govmmQemu.MACVTAP,
-				Driver:        govmmQemu.VirtioNetPCI,
+				Driver:        govmmQemu.VirtioNet,
 				ID:            fmt.Sprintf("network-%d", q.networkIndex),
 				IFName:        ep.Name(),
 				MACAddress:    ep.HardwareAddr(),
@@ -516,7 +519,7 @@ func (q *qemuArchBase) appendBlockDevice(devices []govmmQemu.Device, drive confi
 	return devices
 }
 
-func (q *qemuArchBase) appendVhostUserDevice(devices []govmmQemu.Device, attr config.VhostUserDeviceAttrs) []govmmQemu.Device {
+func (q *qemuArchBase) appendVhostUserDevice(devices []govmmQemu.Device, attr config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error) {
 	qemuVhostUserDevice := govmmQemu.VhostUserDevice{}
 
 	switch attr.Type {
@@ -534,7 +537,7 @@ func (q *qemuArchBase) appendVhostUserDevice(devices []govmmQemu.Device, attr co
 
 	devices = append(devices, qemuVhostUserDevice)
 
-	return devices
+	return devices, nil
 }
 
 func (q *qemuArchBase) appendVFIODevice(devices []govmmQemu.Device, vfioDev config.VFIODev) []govmmQemu.Device {

virtcontainers/qemu_arch_base_test.go

@@ -199,6 +199,7 @@ func TestQemuArchBaseMemoryTopology(t *testing.T) {
 
 func testQemuArchBaseAppend(t *testing.T, structure interface{}, expected []govmmQemu.Device) {
 	var devices []govmmQemu.Device
+	var err error
 	assert := assert.New(t)
 	qemuArchBase := newQemuArchBase()
 
@@ -212,9 +213,10 @@ func testQemuArchBaseAppend(t *testing.T, structure interface{}, expected []govm
 	case config.VFIODev:
 		devices = qemuArchBase.appendVFIODevice(devices, s)
 	case config.VhostUserDeviceAttrs:
-		devices = qemuArchBase.appendVhostUserDevice(devices, s)
+		devices, err = qemuArchBase.appendVhostUserDevice(devices, s)
 	}
 
+	assert.NoError(err)
 	assert.Equal(devices, expected)
 }
 
@@ -471,7 +473,7 @@ func TestQemuArchBaseAppendNetwork(t *testing.T) {
 	expectedOut := []govmmQemu.Device{
 		govmmQemu.NetDevice{
 			Type:       networkModelToQemuType(macvlanEp.NetPair.NetInterworkingModel),
-			Driver:     govmmQemu.VirtioNetPCI,
+			Driver:     govmmQemu.VirtioNet,
 			ID:         fmt.Sprintf("network-%d", 0),
 			IFName:     macvlanEp.NetPair.TAPIface.Name,
 			MACAddress: macvlanEp.NetPair.TAPIface.HardAddr,
@@ -482,7 +484,7 @@ func TestQemuArchBaseAppendNetwork(t *testing.T) {
 		},
 		govmmQemu.NetDevice{
 			Type:       govmmQemu.MACVTAP,
-			Driver:     govmmQemu.VirtioNetPCI,
+			Driver:     govmmQemu.VirtioNet,
 			ID:         fmt.Sprintf("network-%d", 1),
 			IFName:     macvtapEp.Name(),
 			MACAddress: macvtapEp.HardwareAddr(),

virtcontainers/qemu_s390x.go

@@ -0,0 +1,122 @@
+// Copyright (c) 2018 IBM
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package virtcontainers
+
+import (
+	"fmt"
+	govmmQemu "github.com/intel/govmm/qemu"
+	"github.com/kata-containers/runtime/virtcontainers/device/config"
+)
+
+type qemuS390x struct {
+	// inherit from qemuArchBase, overwrite methods if needed
+	qemuArchBase
+}
+
+const defaultQemuPath = "/usr/bin/qemu-system-s390x"
+
+const defaultQemuMachineType = QemuCCWVirtio
+
+const defaultQemuMachineOptions = "accel=kvm"
+
+const defaultPCBridgeBus = "pci.0"
+
+const VirtioSerialCCW = "virtio-serial-ccw"
+
+var qemuPaths = map[string]string{
+	QemuCCWVirtio: defaultQemuPath,
+}
+
+var kernelRootParams = []Param{}
+
+// Verify needed parameters
+var kernelParams = []Param{
+	{"console", "ttysclp0"},
+}
+
+var supportedQemuMachines = []govmmQemu.Machine{
+	{
+		Type:    QemuCCWVirtio,
+		Options: defaultQemuMachineOptions,
+	},
+}
+
+// MaxQemuVCPUs returns the maximum number of vCPUs supported
+func MaxQemuVCPUs() uint32 {
+	// Max number of virtual Cpu defined in qemu. See
+	// https://github.com/qemu/qemu/blob/80422b00196a7af4c6efb628fae0ad8b644e98af/target/s390x/cpu.h#L55
+	// #define S390_MAX_CPUS 248
+	return uint32(248)
+}
+
+func newQemuArch(config HypervisorConfig) qemuArch {
+	machineType := config.HypervisorMachineType
+	if machineType == "" {
+		machineType = defaultQemuMachineType
+	}
+
+	q := &qemuS390x{
+		qemuArchBase{
+			machineType:           machineType,
+			qemuPaths:             qemuPaths,
+			supportedQemuMachines: supportedQemuMachines,
+			kernelParamsNonDebug:  kernelParamsNonDebug,
+			kernelParamsDebug:     kernelParamsDebug,
+			kernelParams:          kernelParams,
+		},
+	}
+
+	if config.ImagePath != "" {
+		q.kernelParams = append(q.kernelParams, kernelRootParams...)
+		q.kernelParamsNonDebug = append(q.kernelParamsNonDebug, kernelParamsSystemdNonDebug...)
+		q.kernelParamsDebug = append(q.kernelParamsDebug, kernelParamsSystemdDebug...)
+	}
+
+	return q
+}
+
+// appendBridges appends to devices the given bridges
+func (q *qemuS390x) appendBridges(devices []govmmQemu.Device, bridges []Bridge) []govmmQemu.Device {
+	return genericAppendBridges(devices, bridges, q.machineType)
+}
+
+// appendConsole appends a console to devices.
+// The function has been overwriten to correctly set the driver to the CCW device
+func (q *qemuS390x) appendConsole(devices []govmmQemu.Device, path string) []govmmQemu.Device {
+	serial := govmmQemu.SerialDevice{
+		Driver:        VirtioSerialCCW,
+		ID:            "serial0",
+		DisableModern: q.nestedRun,
+	}
+
+	devices = append(devices, serial)
+
+	var console govmmQemu.CharDevice
+
+	console = govmmQemu.CharDevice{
+		Driver:   govmmQemu.Console,
+		Backend:  govmmQemu.Socket,
+		DeviceID: "console0",
+		ID:       "charconsole0",
+		Path:     path,
+	}
+
+	devices = append(devices, console)
+
+	return devices
+}
+
+// appendVhostUserDevice throws an error if vhost devices are tried to be used.
+// See issue https://github.com/kata-containers/runtime/issues/659
+func (q *qemuS390x) appendVhostUserDevice(devices []govmmQemu.Device, attr config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error) {
+	return nil, fmt.Errorf("No vhost-user devices supported on s390x")
+}
+
+// supportGuestMemoryHotplug return false for s390x architecture. The pc-dimm backend device for s390x
+// is not support. PC-DIMM is not listed in the devices supported by qemu-system-s390x -device help
+func (q *qemuS390x) supportGuestMemoryHotplug() bool {
+	return false
+}

virtcontainers/qemu_s390x_test.go

@@ -0,0 +1,68 @@
+// Copyright (c) 2018 IBM
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+package virtcontainers
+
+import (
+	"fmt"
+	"testing"
+
+	govmmQemu "github.com/intel/govmm/qemu"
+	"github.com/kata-containers/runtime/virtcontainers/device/config"
+	"github.com/stretchr/testify/assert"
+)
+
+func newTestQemu(machineType string) qemuArch {
+	config := HypervisorConfig{
+		HypervisorMachineType: machineType,
+	}
+	return newQemuArch(config)
+}
+
+func TestQemuS390xCPUModel(t *testing.T) {
+	assert := assert.New(t)
+	s390x := newTestQemu(QemuCCWVirtio)
+
+	expectedOut := defaultCPUModel
+	model := s390x.cpuModel()
+	assert.Equal(expectedOut, model)
+
+	s390x.enableNestingChecks()
+	expectedOut = defaultCPUModel + ",pmu=off"
+	model = s390x.cpuModel()
+	assert.Equal(expectedOut, model)
+}
+
+func TestQemuS390xMemoryTopology(t *testing.T) {
+	assert := assert.New(t)
+	s390x := newTestQemu(QemuCCWVirtio)
+	memoryOffset := 1024
+
+	hostMem := uint64(1024)
+	mem := uint64(120)
+	slots := uint8(10)
+	expectedMemory := govmmQemu.Memory{
+		Size:   fmt.Sprintf("%dM", mem),
+		Slots:  slots,
+		MaxMem: fmt.Sprintf("%dM", hostMem+uint64(memoryOffset)),
+	}
+
+	m := s390x.memoryTopology(mem, hostMem, slots)
+	assert.Equal(expectedMemory, m)
+}
+
+func TestQemuS390xAppendVhostUserDevice(t *testing.T) {
+	macAddress := "00:11:22:33:44:55:66"
+	qemu := qemuS390x{}
+	assert := assert.New(t)
+
+	vhostUserDevice := config.VhostUserDeviceAttrs{
+		Type:       config.VhostUserNet,
+		MacAddress: macAddress,
+	}
+
+	_, err := qemu.appendVhostUserDevice(nil, vhostUserDevice)
+	assert.Error(err)
+}