Hypervisor: UUID fix for acrn hypevisor

This patch adds support for getting the kata UUID from
acrn hypervisor and using these UUID to create a VM.

Fixes: #1785
Signed-off-by: Vijay Dhanraj <vijay.dhanraj@intel.com>

cli/kata-check_amd64.go

@@ -6,6 +6,7 @@
 package main
 
 import (
+	"context"
 	"fmt"
 	"io/ioutil"
 	"strings"
@@ -13,6 +14,7 @@ import (
 	"unsafe"
 
 	vc "github.com/kata-containers/runtime/virtcontainers"
+	"github.com/kata-containers/runtime/virtcontainers/store"
 	"github.com/sirupsen/logrus"
 )
 
@@ -231,27 +233,36 @@ func acrnIsUsable() error {
 		return err
 	}
 	defer syscall.Close(f)
+	kataLog.WithField("device", acrnDevice).Info("device available")
 
-	fieldLogger := kataLog.WithField("check-type", "full")
+	acrnInst := vc.Acrn{}
-
+	vcStore, err := store.NewVCSandboxStore(context.Background(), "kata-check")
-	fieldLogger.WithField("device", acrnDevice).Info("device available")
+	if err != nil {
-
+		return err
-	createVM := acrn_create_vm{
-		uuid: [16]uint8{
-			0xd2, 0x79, 0x54, 0x38, 0x25, 0xd6, 0x11, 0xe8,
-			0x86, 0x4e, 0xcb, 0x7a, 0x18, 0xb3, 0x46, 0x43,
-		},
 	}
 
+	uuidStr, err := acrnInst.GetNextAvailableUUID(vcStore)
+	if err != nil {
+		return err
+	}
+
+	uuid, err := acrnInst.GetACRNUUIDBytes(uuidStr)
+	if err != nil {
+		return fmt.Errorf("Converting UUID str to bytes failed, Err:%s", err)
+	}
+
+	var createVM acrn_create_vm
+	createVM.uuid = uuid
+
 	ret, _, errno := syscall.Syscall(syscall.SYS_IOCTL,
 		uintptr(f),
 		uintptr(ioctl_ACRN_CREATE_VM),
 		uintptr(unsafe.Pointer(&createVM)))
 	if ret != 0 || errno != 0 {
 		if errno == syscall.EBUSY {
-			fieldLogger.WithField("reason", "another hypervisor running").Error("cannot create VM")
+			kataLog.WithField("reason", "another hypervisor running").Error("cannot create VM")
 		}
-		fieldLogger.WithFields(logrus.Fields{
+		kataLog.WithFields(logrus.Fields{
 			"ret":   ret,
 			"errno": errno,
 		}).Info("Create VM Error")
@@ -263,14 +274,14 @@ func acrnIsUsable() error {
 		uintptr(ioctl_ACRN_DESTROY_VM),
 		0)
 	if ret != 0 || errno != 0 {
-		fieldLogger.WithFields(logrus.Fields{
+		kataLog.WithFields(logrus.Fields{
 			"ret":   ret,
 			"errno": errno,
 		}).Info("Destroy VM Error")
 		return errno
 	}
 
-	fieldLogger.WithField("feature", "create-vm").Info("feature available")
+	kataLog.WithField("feature", "create-vm").Info("feature available")
 
 	return nil
 }

virtcontainers/acrn.go

@@ -14,6 +14,7 @@ import (
 	"strings"
 	"syscall"
 	"time"
+	"unsafe"
 
 	opentracing "github.com/opentracing/opentracing-go"
 	"github.com/pkg/errors"
@@ -21,25 +22,57 @@ import (
 
 	"github.com/kata-containers/runtime/virtcontainers/device/config"
 	persistapi "github.com/kata-containers/runtime/virtcontainers/persist/api"
+	"github.com/kata-containers/runtime/virtcontainers/pkg/uuid"
 	"github.com/kata-containers/runtime/virtcontainers/store"
 	"github.com/kata-containers/runtime/virtcontainers/types"
 	"github.com/kata-containers/runtime/virtcontainers/utils"
 )
 
-// AcrnState keeps Acrn's state
+// ACRN currently supports only known UUIDs for security
+// reasons (FuSa). When launching VM, only these pre-defined
+// UUID should be used else VM launch will fail. The main
+// of purpose UUID is is not used for image identification
+// but generating vSeed (virtual seed which takes UUID
+// as one of the parameter) which is used during VM boot.
+
+// acrnUUIDsToIdx lists Idx corresponding to the UUID
+var acrnUUIDsToIdx = map[string]uint8{
+	"a7ada506-1ab0-4b6b-a0da-e513ca9b8c2f": 0,
+	"dbeae168-26e4-4084-9227-622193e56325": 1,
+	"18ed60cd-e9ea-4bf4-8f87-8523fc8347a3": 2,
+	"3f90b6f8-449a-4e72-b99c-063a889fc422": 3,
+	"1ae8587b-e599-4b59-8260-6d14ac166a55": 4,
+	"75f3b94b-49ed-48fc-b019-577ef45adf2b": 5,
+	"ca62cf3c-8359-47e8-a3f7-de2d682dfb02": 6,
+	"e3189497-c3f6-4b97-9e2c-18ac0ab9064d": 7,
+}
+
+// acrnIdxToUUIDs lists UUIDs corresponding to the Idx
+var acrnIdxToUUIDs = map[uint8]string{
+	0: "a7ada506-1ab0-4b6b-a0da-e513ca9b8c2f",
+	1: "dbeae168-26e4-4084-9227-622193e56325",
+	2: "18ed60cd-e9ea-4bf4-8f87-8523fc8347a3",
+	3: "3f90b6f8-449a-4e72-b99c-063a889fc422",
+	4: "1ae8587b-e599-4b59-8260-6d14ac166a55",
+	5: "75f3b94b-49ed-48fc-b019-577ef45adf2b",
+	6: "ca62cf3c-8359-47e8-a3f7-de2d682dfb02",
+	7: "e3189497-c3f6-4b97-9e2c-18ac0ab9064d",
+}
+
+// AcrnInfo keeps track of UUID availability
+type AcrnInfo struct {
+	UUIDAvailability [8]uint8
+}
+
+// AcrnState keeps track of VM UUID, PID.
 type AcrnState struct {
 	UUID string
+	PID  int
 }
 
-// AcrnInfo keeps PID of the hypervisor
+// Acrn is an Hypervisor interface implementation for the Linux acrn hypervisor.
-type AcrnInfo struct {
+type Acrn struct {
-	PID int
+	id         string
-}
-
-// acrn is an Hypervisor interface implementation for the Linux acrn hypervisor.
-type acrn struct {
-	id string
-
 	store      *store.VCStore
 	config     HypervisorConfig
 	acrnConfig Config
@@ -49,17 +82,41 @@ type acrn struct {
 	ctx        context.Context
 }
 
+type acrnPlatformInfo struct {
+	cpuNum            uint16     //nolint
+	reserved0         [126]uint8 //nolint
+	maxVCPUsPerVM     uint16     //nolint
+	maxKataContainers uint8
+	reserved1         [125]uint8 //nolint
+}
+
+const acrnDevice = "/dev/acrn_vhm"
+
+// ioctl_ACRN_CREATE_VM is the IOCTL to create VM in ACRN.
+// Current Linux mainstream kernel doesn't have support for ACRN.
+// Due to this several macros are not defined in Linux headers.
+// Until the support is available, directly use the value instead
+// of macros.
+//https://github.com/kata-containers/runtime/issues/1784
+const ioctl_ACRN_GET_PLATFORM_INFO = 0x43000003 //nolint
+
 const (
 	acrnConsoleSocket          = "console.sock"
 	acrnStopSandboxTimeoutSecs = 15
 )
 
+//UUIDBusy marks a particular UUID as busy
+const UUIDBusy = 1
+
+//UUIDFree marks a particular UUID as free
+const UUIDFree = 0
+
 // agnostic list of kernel parameters
 var acrnDefaultKernelParameters = []Param{
 	{"panic", "1"},
 }
 
-func (a *acrn) kernelParameters() string {
+func (a *Acrn) kernelParameters() string {
 	// get a list of arch kernel parameters
 	params := a.arch.kernelParameters(a.config.Debug)
 
@@ -79,20 +136,20 @@ func (a *acrn) kernelParameters() string {
 	return strings.Join(paramsStr, " ")
 }
 
-// Adds all capabilities supported by acrn implementation of hypervisor interface
+// Adds all capabilities supported by Acrn implementation of hypervisor interface
-func (a *acrn) capabilities() types.Capabilities {
+func (a *Acrn) capabilities() types.Capabilities {
 	span, _ := a.trace("capabilities")
 	defer span.Finish()
 
 	return a.arch.capabilities()
 }
 
-func (a *acrn) hypervisorConfig() HypervisorConfig {
+func (a *Acrn) hypervisorConfig() HypervisorConfig {
 	return a.config
 }
 
 // get the acrn binary path
-func (a *acrn) acrnPath() (string, error) {
+func (a *Acrn) acrnPath() (string, error) {
 	p, err := a.config.HypervisorAssetPath()
 	if err != nil {
 		return "", err
@@ -113,7 +170,7 @@ func (a *acrn) acrnPath() (string, error) {
 }
 
 // get the ACRNCTL binary path
-func (a *acrn) acrnctlPath() (string, error) {
+func (a *Acrn) acrnctlPath() (string, error) {
 	ctlpath, err := a.config.HypervisorCtlAssetPath()
 	if err != nil {
 		return "", err
@@ -134,11 +191,11 @@ func (a *acrn) acrnctlPath() (string, error) {
 }
 
 // Logger returns a logrus logger appropriate for logging acrn messages
-func (a *acrn) Logger() *logrus.Entry {
+func (a *Acrn) Logger() *logrus.Entry {
 	return virtLog.WithField("subsystem", "acrn")
 }
 
-func (a *acrn) trace(name string) (opentracing.Span, context.Context) {
+func (a *Acrn) trace(name string) (opentracing.Span, context.Context) {
 	if a.ctx == nil {
 		a.Logger().WithField("type", "bug").Error("trace called before context set")
 		a.ctx = context.Background()
@@ -152,13 +209,13 @@ func (a *acrn) trace(name string) (opentracing.Span, context.Context) {
 	return span, ctx
 }
 
-func (a *acrn) memoryTopology() (Memory, error) {
+func (a *Acrn) memoryTopology() (Memory, error) {
 	memMb := uint64(a.config.MemorySize)
 
 	return a.arch.memoryTopology(memMb), nil
 }
 
-func (a *acrn) appendImage(devices []Device, imagePath string) ([]Device, error) {
+func (a *Acrn) appendImage(devices []Device, imagePath string) ([]Device, error) {
 	if imagePath == "" {
 		return nil, fmt.Errorf("Image path is empty: %s", imagePath)
 	}
@@ -180,7 +237,7 @@ func (a *acrn) appendImage(devices []Device, imagePath string) ([]Device, error)
 	return devices, nil
 }
 
-func (a *acrn) buildDevices(imagePath string) ([]Device, error) {
+func (a *Acrn) buildDevices(imagePath string) ([]Device, error) {
 	var devices []Device
 
 	if imagePath == "" {
@@ -219,7 +276,7 @@ func (a *acrn) buildDevices(imagePath string) ([]Device, error) {
 }
 
 // setup sets the Acrn structure up.
-func (a *acrn) setup(id string, hypervisorConfig *HypervisorConfig, vcStore *store.VCStore) error {
+func (a *Acrn) setup(id string, hypervisorConfig *HypervisorConfig, vcStore *store.VCStore) error {
 	span, _ := a.trace("setup")
 	defer span.Finish()
 
@@ -234,24 +291,24 @@ func (a *acrn) setup(id string, hypervisorConfig *HypervisorConfig, vcStore *sto
 	a.arch = newAcrnArch(a.config)
 
 	var create bool
+	var uuid string
 
 	if a.store != nil { //use old store
-		if err = a.store.Load(store.Hypervisor, &a.info); err != nil {
+		if err = a.store.Load(store.Hypervisor, &a.state); err != nil {
 			create = true
 		}
-	} else if a.info.PID == 0 { // new store
+	} else if a.state.UUID == "" { // new store
 		create = true
 	}
 
 	if create {
-		// acrn currently supports only known UUIDs for security
+		a.Logger().Debug("Setting UUID")
-		// reasons (FuSa). When launching VM, only these pre-defined
+		if uuid, err = a.GetNextAvailableUUID(nil); err != nil {
-		// UUID should be used else VM launch will fail. acrn team is
+			return err
-		// working on a solution to expose these pre-defined UUIDs
+		}
-		// to Kata in order for it to launch VMs successfully.
+		a.state.UUID = uuid
-		// Until this support is available, Kata is limited to
+		Idx := acrnUUIDsToIdx[uuid]
-		// launch 1 VM (using the default UUID).
+		a.info.UUIDAvailability[Idx] = UUIDBusy
-		// https://github.com/kata-containers/runtime/issues/1785
 
 		// The path might already exist, but in case of VM templating,
 		// we have to create it since the sandbox has not created it yet.
@@ -259,6 +316,10 @@ func (a *acrn) setup(id string, hypervisorConfig *HypervisorConfig, vcStore *sto
 			return err
 		}
 
+		if err = a.storeState(); err != nil {
+			return err
+		}
+
 		if err = a.storeInfo(); err != nil {
 			return err
 		}
@@ -267,7 +328,7 @@ func (a *acrn) setup(id string, hypervisorConfig *HypervisorConfig, vcStore *sto
 	return nil
 }
 
-func (a *acrn) createDummyVirtioBlkDev(devices []Device) ([]Device, error) {
+func (a *Acrn) createDummyVirtioBlkDev(devices []Device) ([]Device, error) {
 	span, _ := a.trace("createDummyVirtioBlkDev")
 	defer span.Finish()
 
@@ -287,7 +348,7 @@ func (a *acrn) createDummyVirtioBlkDev(devices []Device) ([]Device, error) {
 }
 
 // createSandbox is the Hypervisor sandbox creation.
-func (a *acrn) createSandbox(ctx context.Context, id string, networkNS NetworkNamespace, hypervisorConfig *HypervisorConfig, store *store.VCStore) error {
+func (a *Acrn) createSandbox(ctx context.Context, id string, networkNS NetworkNamespace, hypervisorConfig *HypervisorConfig, store *store.VCStore) error {
 	// Save the tracing context
 	a.ctx = ctx
 
@@ -319,8 +380,9 @@ func (a *acrn) createSandbox(ctx context.Context, id string, networkNS NetworkNa
 		Params:    a.kernelParameters(),
 	}
 
-	// Disabling UUID check until the below is fixed.
+	if a.state.UUID == "" {
-	// https://github.com/kata-containers/runtime/issues/1785
+		return fmt.Errorf("ACRN UUID should not be empty")
+	}
 
 	devices, err := a.buildDevices(imagePath)
 	if err != nil {
@@ -338,6 +400,7 @@ func (a *acrn) createSandbox(ctx context.Context, id string, networkNS NetworkNa
 	}
 
 	acrnConfig := Config{
+		UUID:     a.state.UUID,
 		ACPIVirt: true,
 		Path:     acrnPath,
 		CtlPath:  acrnctlPath,
@@ -354,7 +417,7 @@ func (a *acrn) createSandbox(ctx context.Context, id string, networkNS NetworkNa
 }
 
 // startSandbox will start the Sandbox's VM.
-func (a *acrn) startSandbox(timeoutSecs int) error {
+func (a *Acrn) startSandbox(timeoutSecs int) error {
 	span, _ := a.trace("startSandbox")
 	defer span.Finish()
 
@@ -389,7 +452,7 @@ func (a *acrn) startSandbox(timeoutSecs int) error {
 	if err != nil {
 		return fmt.Errorf("%s", strErr)
 	}
-	a.info.PID = PID
+	a.state.PID = PID
 
 	if err = a.waitSandbox(timeoutSecs); err != nil {
 		a.Logger().WithField("acrn wait failed:", err).Debug()
@@ -397,12 +460,15 @@ func (a *acrn) startSandbox(timeoutSecs int) error {
 	}
 
 	//Store VMM information
-	return a.store.Store(store.Hypervisor, a.info)
+	if err = a.storeState(); err != nil {
+		return err
+	}
 
+	return nil
 }
 
 // waitSandbox will wait for the Sandbox's VM to be up and running.
-func (a *acrn) waitSandbox(timeoutSecs int) error {
+func (a *Acrn) waitSandbox(timeoutSecs int) error {
 	span, _ := a.trace("waitSandbox")
 	defer span.Finish()
 
@@ -416,7 +482,7 @@ func (a *acrn) waitSandbox(timeoutSecs int) error {
 }
 
 // stopSandbox will stop the Sandbox's VM.
-func (a *acrn) stopSandbox() (err error) {
+func (a *Acrn) stopSandbox() (err error) {
 	span, _ := a.trace("stopSandbox")
 	defer span.Finish()
 
@@ -430,7 +496,23 @@ func (a *acrn) stopSandbox() (err error) {
 		}
 	}()
 
-	pid := a.info.PID
+	// Mark the UUID as free
+	uuid := a.state.UUID
+	Idx := acrnUUIDsToIdx[uuid]
+
+	if err = a.store.Load(store.UUID, &a.info); err != nil {
+		a.Logger().Info("Failed to load UUID availabiity info")
+		return err
+	}
+
+	a.info.UUIDAvailability[Idx] = UUIDFree
+
+	if err = a.storeInfo(); err != nil {
+		a.Logger().Info("Failed to store UUID availabiity info")
+		return err
+	}
+
+	pid := a.state.PID
 
 	// Check if VM process is running, in case it is not, let's
 	// return from here.
@@ -468,7 +550,7 @@ func (a *acrn) stopSandbox() (err error) {
 
 }
 
-func (a *acrn) updateBlockDevice(drive *config.BlockDrive) error {
+func (a *Acrn) updateBlockDevice(drive *config.BlockDrive) error {
 	var err error
 	if drive.File == "" || drive.Index >= AcrnBlkDevPoolSz {
 		return fmt.Errorf("Empty filepath or invalid drive index, Dive ID:%s, Drive Index:%d",
@@ -494,7 +576,7 @@ func (a *acrn) updateBlockDevice(drive *config.BlockDrive) error {
 	return err
 }
 
-func (a *acrn) hotplugAddDevice(devInfo interface{}, devType deviceType) (interface{}, error) {
+func (a *Acrn) hotplugAddDevice(devInfo interface{}, devType deviceType) (interface{}, error) {
 	span, _ := a.trace("hotplugAddDevice")
 	defer span.Finish()
 
@@ -508,7 +590,7 @@ func (a *acrn) hotplugAddDevice(devInfo interface{}, devType deviceType) (interf
 	}
 }
 
-func (a *acrn) hotplugRemoveDevice(devInfo interface{}, devType deviceType) (interface{}, error) {
+func (a *Acrn) hotplugRemoveDevice(devInfo interface{}, devType deviceType) (interface{}, error) {
 	span, _ := a.trace("hotplugRemoveDevice")
 	defer span.Finish()
 
@@ -517,7 +599,7 @@ func (a *acrn) hotplugRemoveDevice(devInfo interface{}, devType deviceType) (int
 	return nil, nil
 }
 
-func (a *acrn) pauseSandbox() error {
+func (a *Acrn) pauseSandbox() error {
 	span, _ := a.trace("pauseSandbox")
 	defer span.Finish()
 
@@ -526,7 +608,7 @@ func (a *acrn) pauseSandbox() error {
 	return nil
 }
 
-func (a *acrn) resumeSandbox() error {
+func (a *Acrn) resumeSandbox() error {
 	span, _ := a.trace("resumeSandbox")
 	defer span.Finish()
 
@@ -535,8 +617,8 @@ func (a *acrn) resumeSandbox() error {
 	return nil
 }
 
-// addDevice will add extra devices to Acrn command line.
+// addDevice will add extra devices to acrn command line.
-func (a *acrn) addDevice(devInfo interface{}, devType deviceType) error {
+func (a *Acrn) addDevice(devInfo interface{}, devType deviceType) error {
 	var err error
 	span, _ := a.trace("addDevice")
 	defer span.Finish()
@@ -570,14 +652,14 @@ func (a *acrn) addDevice(devInfo interface{}, devType deviceType) error {
 
 // getSandboxConsole builds the path of the console where we can read
 // logs coming from the sandbox.
-func (a *acrn) getSandboxConsole(id string) (string, error) {
+func (a *Acrn) getSandboxConsole(id string) (string, error) {
 	span, _ := a.trace("getSandboxConsole")
 	defer span.Finish()
 
 	return utils.BuildSocketPath(store.RunVMStoragePath, id, acrnConsoleSocket)
 }
 
-func (a *acrn) saveSandbox() error {
+func (a *Acrn) saveSandbox() error {
 	a.Logger().Info("save sandbox")
 
 	// Not supported. return success
@@ -585,14 +667,14 @@ func (a *acrn) saveSandbox() error {
 	return nil
 }
 
-func (a *acrn) disconnect() {
+func (a *Acrn) disconnect() {
 	span, _ := a.trace("disconnect")
 	defer span.Finish()
 
 	// Not supported.
 }
 
-func (a *acrn) getThreadIDs() (vcpuThreadIDs, error) {
+func (a *Acrn) getThreadIDs() (vcpuThreadIDs, error) {
 	span, _ := a.trace("getThreadIDs")
 	defer span.Finish()
 
@@ -602,62 +684,138 @@ func (a *acrn) getThreadIDs() (vcpuThreadIDs, error) {
 	return vcpuThreadIDs{}, nil
 }
 
-func (a *acrn) resizeMemory(reqMemMB uint32, memoryBlockSizeMB uint32, probe bool) (uint32, memoryDevice, error) {
+func (a *Acrn) resizeMemory(reqMemMB uint32, memoryBlockSizeMB uint32, probe bool) (uint32, memoryDevice, error) {
 	return 0, memoryDevice{}, nil
 }
 
-func (a *acrn) resizeVCPUs(reqVCPUs uint32) (currentVCPUs uint32, newVCPUs uint32, err error) {
+func (a *Acrn) resizeVCPUs(reqVCPUs uint32) (currentVCPUs uint32, newVCPUs uint32, err error) {
 	return 0, 0, nil
 }
 
-func (a *acrn) cleanup() error {
+func (a *Acrn) cleanup() error {
 	span, _ := a.trace("cleanup")
 	defer span.Finish()
 
 	return nil
 }
 
-func (a *acrn) getPids() []int {
+func (a *Acrn) getPids() []int {
-	return []int{a.info.PID}
+	return []int{a.state.PID}
 }
 
-func (a *acrn) fromGrpc(ctx context.Context, hypervisorConfig *HypervisorConfig, store *store.VCStore, j []byte) error {
+func (a *Acrn) fromGrpc(ctx context.Context, hypervisorConfig *HypervisorConfig, store *store.VCStore, j []byte) error {
 	return errors.New("acrn is not supported by VM cache")
 }
 
-func (a *acrn) toGrpc() ([]byte, error) {
+func (a *Acrn) toGrpc() ([]byte, error) {
 	return nil, errors.New("acrn is not supported by VM cache")
 }
 
-func (a *acrn) storeInfo() error {
+func (a *Acrn) save() (s persistapi.HypervisorState) {
-	if a.store != nil {
+	s.Pid = a.state.PID
-		if err := a.store.Store(store.Hypervisor, a.info); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func (a *acrn) save() (s persistapi.HypervisorState) {
-	s.Pid = a.info.PID
 	s.Type = string(AcrnHypervisor)
 	s.UUID = a.state.UUID
 	return
 }
 
-func (a *acrn) load(s persistapi.HypervisorState) {
+func (a *Acrn) load(s persistapi.HypervisorState) {
-	a.info.PID = s.Pid
+	a.state.PID = s.Pid
 	a.state.UUID = s.UUID
 }
 
-func (a *acrn) check() error {
+func (a *Acrn) check() error {
-	if err := syscall.Kill(a.info.PID, syscall.Signal(0)); err != nil {
+	if err := syscall.Kill(a.state.PID, syscall.Signal(0)); err != nil {
 		return errors.Wrapf(err, "failed to ping acrn process")
 	}
 
 	return nil
 }
 
-func (a *acrn) generateSocket(id string, useVsock bool) (interface{}, error) {
+func (a *Acrn) generateSocket(id string, useVsock bool) (interface{}, error) {
 	return generateVMSocket(id, useVsock)
 }
+
+// GetACRNUUIDBytes returns UUID bytes that is used for VM creation
+func (a *Acrn) GetACRNUUIDBytes(uid string) (uuid.UUID, error) {
+	return uuid.Parse(uid)
+}
+
+// GetNextAvailableUUID returns next available UUID VM creation
+// If no validl UUIDs are available it returns err.
+func (a *Acrn) GetNextAvailableUUID(uuidstore *store.VCStore) (string, error) {
+	var MaxVMSupported uint8
+	var Idx uint8
+	var uuidStr string
+	var err error
+
+	if uuidstore == nil {
+		uuidstore = a.store
+	}
+
+	if uuidstore != nil { //use old store
+		if err = uuidstore.Load(store.UUID, &a.info); err != nil {
+			a.Logger().Infof("Load UUID store failed")
+		}
+	}
+
+	if MaxVMSupported, err = a.GetMaxSupportedACRNVM(); err != nil {
+		return "", fmt.Errorf("IOCTL GetMaxSupportedACRNVM failed")
+	}
+
+	for Idx = 0; Idx < MaxVMSupported; Idx++ {
+		if a.info.UUIDAvailability[Idx] == UUIDFree {
+			uuidStr = acrnIdxToUUIDs[Idx]
+			break
+		}
+	}
+
+	if uuidStr == "" {
+		return "", fmt.Errorf("Invalid UUID: Max VMs reached")
+	}
+
+	return uuidStr, nil
+}
+
+// GetMaxSupportedACRNVM checks the max number of VMs that can be
+// launched from kata-runtime.
+func (a *Acrn) GetMaxSupportedACRNVM() (uint8, error) {
+	flags := syscall.O_RDWR | syscall.O_CLOEXEC
+
+	f, err := syscall.Open(acrnDevice, flags, 0)
+	if err != nil {
+		return 0, err
+	}
+	defer syscall.Close(f)
+
+	var platformInfo acrnPlatformInfo
+
+	ret, _, errno := syscall.Syscall(syscall.SYS_IOCTL,
+		uintptr(f),
+		uintptr(ioctl_ACRN_GET_PLATFORM_INFO),
+		uintptr(unsafe.Pointer(&platformInfo)))
+	if ret != 0 || errno != 0 {
+		return 0, errno
+	}
+
+	return platformInfo.maxKataContainers, nil
+}
+
+func (a *Acrn) storeState() error {
+	if a.store != nil {
+		if err := a.store.Store(store.Hypervisor, a.state); err != nil {
+			a.Logger().WithError(err).Error("failed to store acrn state")
+			return err
+		}
+	}
+	return nil
+}
+
+func (a *Acrn) storeInfo() error {
+	if a.store != nil {
+		if err := a.store.Store(store.UUID, a.info); err != nil {
+			a.Logger().WithError(err).Error("failed to store acrn info")
+			return err
+		}
+	}
+	return nil
+}

virtcontainers/acrn_test.go

@@ -8,7 +8,6 @@ package virtcontainers
 import (
 	"context"
 	"fmt"
-	"os"
 	"path/filepath"
 	"testing"
 
@@ -44,7 +43,7 @@ func testAcrnKernelParameters(t *testing.T, kernelParams []Param, debug bool) {
 		acrnConfig.Debug = true
 	}
 
-	a := &acrn{
+	a := &Acrn{
 		config: acrnConfig,
 		arch:   &acrnArchBase{},
 	}
@@ -73,7 +72,7 @@ func TestAcrnKernelParameters(t *testing.T) {
 
 func TestAcrnCapabilities(t *testing.T) {
 	assert := assert.New(t)
-	a := &acrn{
+	a := &Acrn{
 		ctx:  context.Background(),
 		arch: &acrnArchBase{},
 	}
@@ -85,7 +84,7 @@ func TestAcrnCapabilities(t *testing.T) {
 
 func testAcrnAddDevice(t *testing.T, devInfo interface{}, devType deviceType, expected []Device) {
 	assert := assert.New(t)
-	a := &acrn{
+	a := &Acrn{
 		ctx:  context.Background(),
 		arch: &acrnArchBase{},
 	}
@@ -139,7 +138,7 @@ func TestAcrnHotplugUnsupportedDeviceType(t *testing.T) {
 	assert := assert.New(t)
 
 	acrnConfig := newAcrnConfig()
-	a := &acrn{
+	a := &Acrn{
 		ctx:    context.Background(),
 		id:     "acrnTest",
 		config: acrnConfig,
@@ -156,7 +155,7 @@ func TestAcrnUpdateBlockDeviceInvalidPath(t *testing.T) {
 	index := 1
 
 	acrnConfig := newAcrnConfig()
-	a := &acrn{
+	a := &Acrn{
 		ctx:    context.Background(),
 		id:     "acrnBlkTest",
 		config: acrnConfig,
@@ -178,7 +177,7 @@ func TestAcrnUpdateBlockDeviceInvalidIdx(t *testing.T) {
 	index := AcrnBlkDevPoolSz + 1
 
 	acrnConfig := newAcrnConfig()
-	a := &acrn{
+	a := &Acrn{
 		ctx:    context.Background(),
 		id:     "acrnBlkTest",
 		config: acrnConfig,
@@ -195,7 +194,7 @@ func TestAcrnUpdateBlockDeviceInvalidIdx(t *testing.T) {
 
 func TestAcrnGetSandboxConsole(t *testing.T) {
 	assert := assert.New(t)
-	a := &acrn{
+	a := &Acrn{
 		ctx: context.Background(),
 	}
 	sandboxID := "testSandboxID"
@@ -209,7 +208,7 @@ func TestAcrnGetSandboxConsole(t *testing.T) {
 func TestAcrnCreateSandbox(t *testing.T) {
 	assert := assert.New(t)
 	acrnConfig := newAcrnConfig()
-	a := &acrn{}
+	a := &Acrn{}
 
 	sandbox := &Sandbox{
 		ctx: context.Background(),
@@ -219,6 +218,11 @@ func TestAcrnCreateSandbox(t *testing.T) {
 		},
 	}
 
+	// Even though this test doesn't need to create a vcStore,
+	// we are forced to create a vcStore as GetAndSetSandboxBlockIndex()
+	// which is called from createSandbox needs a valid vcStore. vcStore
+	// creation can be removed once https://github.com/kata-containers/runtime/issues/2026
+	// issue is resolved.
 	vcStore, err := store.NewVCSandboxStore(sandbox.ctx, sandbox.id)
 	assert.NoError(err)
 	sandbox.store = vcStore
@@ -228,12 +232,10 @@ func TestAcrnCreateSandbox(t *testing.T) {
 
 	defer globalSandboxList.removeSandbox(sandbox.id)
 
-	// Create the hypervisor fake binary
+	//set PID to 1 to ignore hypercall to get UUID and set a random UUID
-	testAcrnPath := filepath.Join(testDir, testHypervisor)
+	a.state.PID = 1
-	_, err = os.Create(testAcrnPath)
+	a.state.UUID = "f81d4fae-7dec-11d0-a765-00a0c91e6bf6"
-	assert.NoError(err)
+	err = a.createSandbox(context.Background(), sandbox.id, NetworkNamespace{}, &sandbox.config.HypervisorConfig, nil)
-
-	err = a.createSandbox(context.Background(), sandbox.id, NetworkNamespace{}, &sandbox.config.HypervisorConfig, sandbox.store)
 	assert.NoError(err)
 	assert.Exactly(acrnConfig, a.config)
 }
@@ -242,7 +244,7 @@ func TestAcrnMemoryTopology(t *testing.T) {
 	mem := uint32(1000)
 	assert := assert.New(t)
 
-	a := &acrn{
+	a := &Acrn{
 		arch: &acrnArchBase{},
 		config: HypervisorConfig{
 			MemorySize: mem,

virtcontainers/hypervisor.go

@@ -172,7 +172,7 @@ func newHypervisor(hType HypervisorType) (hypervisor, error) {
 	case FirecrackerHypervisor:
 		return &firecracker{}, nil
 	case AcrnHypervisor:
-		return &acrn{}, nil
+		return &Acrn{}, nil
 	case MockHypervisor:
 		return &mockHypervisor{}, nil
 	default:

virtcontainers/store/filesystem_backend.go

@@ -46,6 +46,9 @@ const (
 
 	// DevicesFile is the file name storing a container's devices.
 	DevicesFile = "devices.json"
+
+	// uuidFile is the file name storing a guest VM uuid state.
+	uuidFile = "uuid.json"
 )
 
 // DirMode is the permission bits used for creating a directory
@@ -63,6 +66,9 @@ const SandboxPathSuffix = "sbs"
 // VMPathSuffix is the suffix used for guest VMs.
 const VMPathSuffix = "vm"
 
+// UUIDPathSuffix is the suffix used for uuid storage
+const UUIDPathSuffix = "uuid"
+
 // ConfigStoragePath is the sandbox configuration directory.
 // It will contain one config.json file for each created sandbox.
 var ConfigStoragePath = filepath.Join("/var/lib", StoragePathSuffix, SandboxPathSuffix)
@@ -75,6 +81,10 @@ var RunStoragePath = filepath.Join("/run", StoragePathSuffix, SandboxPathSuffix)
 // It will contain all guest vm sockets and shared mountpoints.
 var RunVMStoragePath = filepath.Join("/run", StoragePathSuffix, VMPathSuffix)
 
+// VMUUIDStoragePath is the uuid directory.
+// It will contain all uuid info used by guest vm.
+var VMUUIDStoragePath = filepath.Join("/var/lib", StoragePathSuffix, UUIDPathSuffix)
+
 func itemToFile(item Item) (string, error) {
 	switch item {
 	case Configuration:
@@ -95,6 +105,8 @@ func itemToFile(item Item) (string, error) {
 		return MountsFile, nil
 	case Devices, DeviceIDs:
 		return DevicesFile, nil
+	case UUID:
+		return uuidFile, nil
 	}
 
 	return "", fmt.Errorf("Unknown item %s", item)

virtcontainers/store/manager.go

@@ -48,6 +48,9 @@ const (
 
 	// DeviceIDs represents a set of reference IDs item to be stored.
 	DeviceIDs
+
+	// UUID represents a set of uuids item to be stored.
+	UUID
 )
 
 func (i Item) String() string {

virtcontainers/store/vc.go

@@ -25,7 +25,7 @@ import (
 //
 // VCStore simply dispatches items into the right Store.
 type VCStore struct {
-	config, state *Store
+	config, state, uuid *Store
 }
 
 func (s *VCStore) itemToStore(item Item) *Store {
@@ -34,6 +34,8 @@ func (s *VCStore) itemToStore(item Item) *Store {
 		return s.config
 	case State, Network, Hypervisor, Agent, Process, Lock, Mounts, Devices, DeviceIDs:
 		return s.state
+	case UUID:
+		return s.uuid
 	}
 
 	return s.state
@@ -51,9 +53,15 @@ func NewVCStore(ctx context.Context, configRoot, stateRoot string) (*VCStore, er
 		return nil, err
 	}
 
+	uuid, err := New(ctx, VCStoreUUIDPath())
+	if err != nil {
+		return nil, err
+	}
+
 	return &VCStore{
 		config: config,
 		state:  state,
+		uuid:   uuid,
 	}, nil
 }
 
@@ -109,7 +117,7 @@ func (s *VCStore) Delete() error {
 	return nil
 }
 
-// LoadSandboxState loads an returns a virtcontainer state
+// LoadState loads an returns a virtcontainer state
 func (s *VCStore) LoadState() (types.SandboxState, error) {
 	var state types.SandboxState
 
@@ -256,6 +264,11 @@ func SandboxConfigurationItemPath(id string, item Item) (string, error) {
 	return filepath.Join(ConfigStoragePath, id, itemFile), nil
 }
 
+// VCStoreUUIDPath returns a virtcontainers runtime uuid URL.
+func VCStoreUUIDPath() string {
+	return filesystemScheme + "://" + VMUUIDStoragePath
+}
+
 // SandboxRuntimeRoot returns a virtcontainers sandbox runtime root URL.
 // This will hold data related to a sandbox run-time state that will not
 // be persistent across host reboots.