sync opencontainers runc/libcontainer with runtime-spec

spec.patch

diff --git a/libcontainer/cgroups/fs/hugetlb.go b/libcontainer/cgroups/fs/hugetlb.go
index 2f97277..b056d02 100644
--- a/libcontainer/cgroups/fs/hugetlb.go
+++ b/libcontainer/cgroups/fs/hugetlb.go
@@ -28,7 +28,7 @@ func (s *HugetlbGroup) Apply(d *cgroupData) error {
 
 func (s *HugetlbGroup) Set(path string, cgroup *configs.Cgroup) error {
 	for _, hugetlb := range cgroup.Resources.HugetlbLimit {
-		if err := writeFile(path, strings.Join([]string{"hugetlb", hugetlb.Pagesize, "limit_in_bytes"}, "."), strconv.FormatUint(hugetlb.Limit, 10)); err != nil {
+		if err := writeFile(path, strings.Join([]string{"hugetlb", hugetlb.Pagesize, "limit_in_bytes"}, "."), strconv.FormatInt(hugetlb.Limit, 10)); err != nil {
 			return err
 		}
 	}
diff --git a/libcontainer/configs/hugepage_limit.go b/libcontainer/configs/hugepage_limit.go
index d302163..0714241 100644
--- a/libcontainer/configs/hugepage_limit.go
+++ b/libcontainer/configs/hugepage_limit.go
@@ -5,5 +5,5 @@ type HugepageLimit struct {
 	Pagesize string `json:"page_size"`
 
 	// usage limit for hugepage.
-	Limit uint64 `json:"limit"`
+	Limit int64 `json:"limit"`
 }
diff --git a/libcontainer/specconv/spec_linux.go b/libcontainer/specconv/spec_linux.go
index 94afd65..2de983c 100644
--- a/libcontainer/specconv/spec_linux.go
+++ b/libcontainer/specconv/spec_linux.go
@@ -262,10 +262,10 @@ func createCgroupConfig(name string, useSystemdCgroup bool, spec *specs.Spec) (*
 		Resources: &configs.Resources{},
 	}
 
-	if spec.Linux != nil && spec.Linux.CgroupsPath != nil {
-		myCgroupPath = libcontainerUtils.CleanPath(*spec.Linux.CgroupsPath)
+	if spec.Linux != nil && spec.Linux.CgroupsPath != "" {
+		myCgroupPath = libcontainerUtils.CleanPath(spec.Linux.CgroupsPath)
 		if useSystemdCgroup {
-			myCgroupPath = *spec.Linux.CgroupsPath
+			myCgroupPath = spec.Linux.CgroupsPath
 		}
 	}
 
@@ -306,16 +306,17 @@ func createCgroupConfig(name string, useSystemdCgroup bool, spec *specs.Spec) (*
 			major = int64(-1)
 			minor = int64(-1)
 		)
-		if d.Type != nil {
-			t = *d.Type
-		}
+               if d.Type != "" {
+                       t = d.Type
+               }
+
 		if d.Major != nil {
 			major = *d.Major
 		}
 		if d.Minor != nil {
 			minor = *d.Minor
 		}
-		if d.Access == nil || *d.Access == "" {
+		if d.Access == "" {
 			return nil, fmt.Errorf("device access at %d field cannot be empty", i)
 		}
 		dt, err := stringToDeviceRune(t)
@@ -326,7 +327,7 @@ func createCgroupConfig(name string, useSystemdCgroup bool, spec *specs.Spec) (*
 			Type:        dt,
 			Major:       major,
 			Minor:       minor,
-			Permissions: *d.Access,
+			Permissions: d.Access,
 			Allow:       d.Allow,
 		}
 		c.Resources.Devices = append(c.Resources.Devices, dd)
@@ -370,11 +371,11 @@ func createCgroupConfig(name string, useSystemdCgroup bool, spec *specs.Spec) (*
 		if r.CPU.RealtimePeriod != nil {
 			c.Resources.CpuRtPeriod = int64(*r.CPU.RealtimePeriod)
 		}
-		if r.CPU.Cpus != nil {
-			c.Resources.CpusetCpus = *r.CPU.Cpus
+		if r.CPU.Cpus != "" {
+			c.Resources.CpusetCpus = r.CPU.Cpus
 		}
-		if r.CPU.Mems != nil {
-			c.Resources.CpusetMems = *r.CPU.Mems
+		if r.CPU.Mems != "" {
+			c.Resources.CpusetMems = r.CPU.Mems
 		}
 	}
 	if r.Pids != nil {