Bump github.com/containers/storage from 1.25.0 to 1.28.0

Bumps [github.com/containers/storage](https://github.com/containers/storage) from 1.25.0 to 1.28.0.
- [Release notes](https://github.com/containers/storage/releases)
- [Changelog](https://github.com/containers/storage/blob/master/docs/containers-storage-changes.md)
- [Commits](https://github.com/containers/storage/compare/v1.25.0...v1.28.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>

20 files changed, 615 insertions, 159 deletions

diff --git a/vendor/github.com/containerd/cgroups/stats/v1/metrics.pb.go b/vendor/github.com/containerd/cgroups/stats/v1/metrics.pb.go
index 713376d5e..a530f1d8f 100644
--- a/vendor/github.com/containerd/cgroups/stats/v1/metrics.pb.go
+++ b/vendor/github.com/containerd/cgroups/stats/v1/metrics.pb.go
@@ -33,6 +33,7 @@ type Metrics struct {
 	Rdma                 *RdmaStat      `protobuf:"bytes,6,opt,name=rdma,proto3" json:"rdma,omitempty"`
 	Network              []*NetworkStat `protobuf:"bytes,7,rep,name=network,proto3" json:"network,omitempty"`
 	CgroupStats          *CgroupStats   `protobuf:"bytes,8,opt,name=cgroup_stats,json=cgroupStats,proto3" json:"cgroup_stats,omitempty"`
+	MemoryOomControl     *MemoryOomControl `protobuf:"bytes,9,opt,name=memory_oom_control,json=MemoryOomControl,proto3" json:"memory_oom_control,omitempty"`
 	XXX_NoUnkeyedLiteral struct{}       `json:"-"`
 	XXX_unrecognized     []byte         `json:"-"`
 	XXX_sizecache        int32          `json:"-"`
@@ -392,6 +393,47 @@ func (m *MemoryEntry) XXX_DiscardUnknown() {
 
 var xxx_messageInfo_MemoryEntry proto.InternalMessageInfo
 
+type MemoryOomControl struct {
+	OomKillDisable   uint64   `protobuf:"varint,1,opt,name=oom_kill_disable,proto3" json:oom_kill_disable",omitempty"`
+	UnderOom         uint64   `protobuf:"varint,2,opt,name=under_oom,proto3" json:"under_oom,omitempty"`
+	OomKill          uint64   `protobuf:"varint,3,opt,name=oom_kill,proto3" json:"oom_kill,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *MemoryOomControl) Reset()  { *m = MemoryOomControl{} }
+func (*MemoryOomControl) ProtoMessage() {}
+func (*MemoryOomControl) Descriptor() ([]byte, []int) {
+	return fileDescriptor_a17b2d87c332bfaa, []int{8}
+}
+func (m *MemoryOomControl) XXX_Unmarshal(b []byte) error {
+	return m.Unmarshal(b)
+}
+func (m *MemoryOomControl) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	if deterministic {
+		return xxx_messageInfo_MemoryOomControl.Marshal(b, m, deterministic)
+	} else {
+		b = b[:cap(b)]
+		n, err := m.MarshalTo(b)
+		if err != nil {
+			return nil, err
+		}
+		return b[:n], nil
+	}
+}
+func (m *MemoryOomControl) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_MemoryOomControl.Merge(m, src)
+}
+func (m *MemoryOomControl) XXX_Size() int {
+	return m.Size()
+}
+func (m *MemoryOomControl) XXX_DiscardUnknown() {
+	xxx_messageInfo_MemoryOomControl.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_MemoryOomControl proto.InternalMessageInfo
+
 type BlkIOStat struct {
 	IoServiceBytesRecursive []*BlkIOEntry `protobuf:"bytes,1,rep,name=io_service_bytes_recursive,json=ioServiceBytesRecursive,proto3" json:"io_service_bytes_recursive,omitempty"`
 	IoServicedRecursive     []*BlkIOEntry `protobuf:"bytes,2,rep,name=io_serviced_recursive,json=ioServicedRecursive,proto3" json:"io_serviced_recursive,omitempty"`
@@ -409,7 +451,7 @@ type BlkIOStat struct {
 func (m *BlkIOStat) Reset()      { *m = BlkIOStat{} }
 func (*BlkIOStat) ProtoMessage() {}
 func (*BlkIOStat) Descriptor() ([]byte, []int) {
-	return fileDescriptor_a17b2d87c332bfaa, []int{8}
+	return fileDescriptor_a17b2d87c332bfaa, []int{9}
 }
 func (m *BlkIOStat) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -452,7 +494,7 @@ type BlkIOEntry struct {
 func (m *BlkIOEntry) Reset()      { *m = BlkIOEntry{} }
 func (*BlkIOEntry) ProtoMessage() {}
 func (*BlkIOEntry) Descriptor() ([]byte, []int) {
-	return fileDescriptor_a17b2d87c332bfaa, []int{9}
+	return fileDescriptor_a17b2d87c332bfaa, []int{10}
 }
 func (m *BlkIOEntry) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -492,7 +534,7 @@ type RdmaStat struct {
 func (m *RdmaStat) Reset()      { *m = RdmaStat{} }
 func (*RdmaStat) ProtoMessage() {}
 func (*RdmaStat) Descriptor() ([]byte, []int) {
-	return fileDescriptor_a17b2d87c332bfaa, []int{10}
+	return fileDescriptor_a17b2d87c332bfaa, []int{11}
 }
 func (m *RdmaStat) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -533,7 +575,7 @@ type RdmaEntry struct {
 func (m *RdmaEntry) Reset()      { *m = RdmaEntry{} }
 func (*RdmaEntry) ProtoMessage() {}
 func (*RdmaEntry) Descriptor() ([]byte, []int) {
-	return fileDescriptor_a17b2d87c332bfaa, []int{11}
+	return fileDescriptor_a17b2d87c332bfaa, []int{12}
 }
 func (m *RdmaEntry) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -580,7 +622,7 @@ type NetworkStat struct {
 func (m *NetworkStat) Reset()      { *m = NetworkStat{} }
 func (*NetworkStat) ProtoMessage() {}
 func (*NetworkStat) Descriptor() ([]byte, []int) {
-	return fileDescriptor_a17b2d87c332bfaa, []int{12}
+	return fileDescriptor_a17b2d87c332bfaa, []int{13}
 }
 func (m *NetworkStat) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -629,7 +671,7 @@ type CgroupStats struct {
 func (m *CgroupStats) Reset()      { *m = CgroupStats{} }
 func (*CgroupStats) ProtoMessage() {}
 func (*CgroupStats) Descriptor() ([]byte, []int) {
-	return fileDescriptor_a17b2d87c332bfaa, []int{13}
+	return fileDescriptor_a17b2d87c332bfaa, []int{14}
 }
 func (m *CgroupStats) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -667,6 +709,7 @@ func init() {
 	proto.RegisterType((*Throttle)(nil), "io.containerd.cgroups.v1.Throttle")
 	proto.RegisterType((*MemoryStat)(nil), "io.containerd.cgroups.v1.MemoryStat")
 	proto.RegisterType((*MemoryEntry)(nil), "io.containerd.cgroups.v1.MemoryEntry")
+	proto.RegisterType((*MemoryOomControl)(nil), "io.containerd.cgroups.v1.MemoryOomControl")
 	proto.RegisterType((*BlkIOStat)(nil), "io.containerd.cgroups.v1.BlkIOStat")
 	proto.RegisterType((*BlkIOEntry)(nil), "io.containerd.cgroups.v1.BlkIOEntry")
 	proto.RegisterType((*RdmaStat)(nil), "io.containerd.cgroups.v1.RdmaStat")
@@ -887,6 +930,16 @@ func (m *Metrics) MarshalTo(dAtA []byte) (int, error) {
 		}
 		i += n6
 	}
+	if m.MemoryOomControl != nil {
+		dAtA[i] = 0x4a
+		i++
+		i = encodeVarintMetrics(dAtA, i, uint64(m.MemoryOomControl.Size()))
+		n7, err := m.MemoryOomControl.MarshalTo(dAtA[i:])
+		if err != nil {
+			return 0, err
+		}
+		i += n7
+	}
 	if m.XXX_unrecognized != nil {
 		i += copy(dAtA[i:], m.XXX_unrecognized)
 	}
@@ -1400,6 +1453,39 @@ func (m *MemoryEntry) MarshalTo(dAtA []byte) (int, error) {
 	return i, nil
 }
 
+func (m *MemoryOomControl) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalTo(dAtA)
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *MemoryOomControl) MarshalTo(dAtA []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if m.OomKillDisable != 0 {
+		dAtA[i] = 0x8
+		i++
+		i = encodeVarintMetrics(dAtA, i, uint64(m.OomKillDisable))
+	}
+	if m.UnderOom != 0 {
+		dAtA[i] = 0x10
+		i++
+		i = encodeVarintMetrics(dAtA, i, uint64(m.UnderOom))
+	}
+	if m.OomKill != 0 {
+		dAtA[i] = 0x18
+		i++
+		i = encodeVarintMetrics(dAtA, i, uint64(m.OomKill))
+	}
+	return i, nil
+}
+
 func (m *BlkIOStat) Marshal() (dAtA []byte, err error) {
 	size := m.Size()
 	dAtA = make([]byte, size)
@@ -1811,6 +1897,10 @@ func (m *Metrics) Size() (n int) {
 		l = m.CgroupStats.Size()
 		n += 1 + l + sovMetrics(uint64(l))
 	}
+	if m.MemoryOomControl != nil {
+		l = m.MemoryOomControl.Size()
+		n += 1 + l + sovMetrics(uint64(l))
+	}
 	if m.XXX_unrecognized != nil {
 		n += len(m.XXX_unrecognized)
 	}
@@ -2077,6 +2167,27 @@ func (m *MemoryEntry) Size() (n int) {
 	return n
 }
 
+func (m *MemoryOomControl) Size() (n int) {
+	if m == nil {
+		return 0
+	}
+	var l int
+	_ = l
+	if m.OomKillDisable != 0 {
+		n += 1 + sovMetrics(uint64(m.OomKillDisable))
+	}
+	if m.UnderOom != 0 {
+		n += 1 + sovMetrics(uint64(m.UnderOom))
+	}
+	if m.OomKill != 0 {
+		n += 1 + sovMetrics(uint64(m.OomKill))
+	}
+	if m.XXX_unrecognized != nil {
+		n += len(m.XXX_unrecognized)
+	}
+	return n
+}
+
 func (m *BlkIOStat) Size() (n int) {
 	if m == nil {
 		return 0
@@ -2301,6 +2412,7 @@ func (this *Metrics) String() string {
 		`Pids:` + strings.Replace(fmt.Sprintf("%v", this.Pids), "PidsStat", "PidsStat", 1) + `,`,
 		`CPU:` + strings.Replace(fmt.Sprintf("%v", this.CPU), "CPUStat", "CPUStat", 1) + `,`,
 		`Memory:` + strings.Replace(fmt.Sprintf("%v", this.Memory), "MemoryStat", "MemoryStat", 1) + `,`,
+		`MemoryOomControl:` + strings.Replace(fmt.Sprintf("%v", this.MemoryOomControl), "MemoryOomControl", "MemoryOomControl", 1) + `,`,
 		`Blkio:` + strings.Replace(fmt.Sprintf("%v", this.Blkio), "BlkIOStat", "BlkIOStat", 1) + `,`,
 		`Rdma:` + strings.Replace(fmt.Sprintf("%v", this.Rdma), "RdmaStat", "RdmaStat", 1) + `,`,
 		`Network:` + strings.Replace(fmt.Sprintf("%v", this.Network), "NetworkStat", "NetworkStat", 1) + `,`,
@@ -2435,6 +2547,19 @@ func (this *MemoryEntry) String() string {
 	}, "")
 	return s
 }
+func (this *MemoryOomControl) String() string {
+	if this == nil {
+		return "nil"
+	}
+	s := strings.Join([]string{`&MemoryOomControl{`,
+		`OomKillDisable:` + fmt.Sprintf("%v", this.OomKillDisable) + `,`,
+		`UnderOom:` + fmt.Sprintf("%v", this.UnderOom) + `,`,
+		`OomKill:` + fmt.Sprintf("%v", this.OomKill) + `,`,
+		`XXX_unrecognized:` + fmt.Sprintf("%v", this.XXX_unrecognized) + `,`,
+		`}`,
+	}, "")
+	return s
+}
 func (this *BlkIOStat) String() string {
 	if this == nil {
 		return "nil"
@@ -2848,6 +2973,41 @@ func (m *Metrics) Unmarshal(dAtA []byte) error {
 				return err
 			}
 			iNdEx = postIndex
+		case 9:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field MemoryOomControl", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowMetrics
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				msglen |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthMetrics
+			}
+			postIndex := iNdEx + msglen
+			if postIndex < 0 {
+				return ErrInvalidLengthMetrics
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			if m.MemoryOomControl == nil {
+				m.MemoryOomControl = &MemoryOomControl{}
+			}
+			if err := m.MemoryOomControl.Unmarshal(dAtA[iNdEx:postIndex]); err != nil {
+				return err
+			}
 		default:
 			iNdEx = preIndex
 			skippy, err := skipMetrics(dAtA[iNdEx:])
@@ -4468,6 +4628,117 @@ func (m *MemoryEntry) Unmarshal(dAtA []byte) error {
 	}
 	return nil
 }
+func (m *MemoryOomControl) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowMetrics
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= uint64(b&0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: MemoryOomControl: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: MemoryOomControl: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field OomKillDisable", wireType)
+			}
+			m.OomKillDisable = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowMetrics
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.OomKillDisable |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 2:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field UnderOom", wireType)
+			}
+			m.UnderOom = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowMetrics
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.UnderOom |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field OomKill", wireType)
+			}
+			m.OomKill = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowMetrics
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.OomKill |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			iNdEx = preIndex
+			skippy, err := skipMetrics(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthMetrics
+			}
+			if (iNdEx + skippy) < 0 {
+				return ErrInvalidLengthMetrics
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.XXX_unrecognized = append(m.XXX_unrecognized, dAtA[iNdEx:iNdEx+skippy]...)
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
 func (m *BlkIOStat) Unmarshal(dAtA []byte) error {
 	l := len(dAtA)
 	iNdEx := 0
diff --git a/vendor/github.com/containerd/cgroups/stats/v1/metrics.pb.txt b/vendor/github.com/containerd/cgroups/stats/v1/metrics.pb.txt
index b7e87f00a..3ed0898cc 100644
--- a/vendor/github.com/containerd/cgroups/stats/v1/metrics.pb.txt
+++ b/vendor/github.com/containerd/cgroups/stats/v1/metrics.pb.txt
@@ -71,6 +71,14 @@ file {
       type_name: ".io.containerd.cgroups.v1.CgroupStats"
       json_name: "cgroupStats"
     }
+    field {
+      name: "memory_oom_control"
+      number: 9
+      label: LABEL_OPTIONAL
+      type: TYPE_MESSAGE
+      type_name: ".io.containerd.cgroups.v1.MemoryOomControl"
+      json_name: "memoryOomControl"
+    }
   }
   message_type {
     name: "HugetlbStat"
@@ -503,6 +511,30 @@ file {
     }
   }
   message_type {
+    name: "MemoryOomControl"
+    field {
+      name: "oom_kill_disable"
+      number: 1
+      label: LABEL_OPTIONAL
+      type: TYPE_UINT64
+      json_name: "oom_kill_disable"
+    }
+    field {
+      name: "under_oom"
+      number: 2
+      label: LABEL_OPTIONAL
+      type: TYPE_UINT64
+      json_name: "under_oom"
+    }
+    field {
+      name: "oom_kill"
+      number: 3
+      label: LABEL_OPTIONAL
+      type: TYPE_UINT64
+      json_name: "oom_kill"
+    }
+  }
+  message_type {
     name: "BlkIOStat"
     field {
       name: "io_service_bytes_recursive"
diff --git a/vendor/github.com/containerd/cgroups/stats/v1/metrics.proto b/vendor/github.com/containerd/cgroups/stats/v1/metrics.proto
index ba6be851d..b3f6cc37d 100644
--- a/vendor/github.com/containerd/cgroups/stats/v1/metrics.proto
+++ b/vendor/github.com/containerd/cgroups/stats/v1/metrics.proto
@@ -13,6 +13,7 @@ message Metrics {
 	RdmaStat rdma = 6;
 	repeated NetworkStat network = 7;
 	CgroupStats cgroup_stats = 8;
+	MemoryOomControl memory_oom_control = 9;
 }
 
 message HugetlbStat {
@@ -94,6 +95,12 @@ message MemoryEntry {
 	uint64 failcnt = 4;
 }
 
+message MemoryOomControl {
+	uint64 oom_kill_disable = 1;
+	uint64 under_oom = 2;
+	uint64 oom_kill = 3;
+}
+
 message BlkIOStat {
 	repeated BlkIOEntry io_service_bytes_recursive = 1;
 	repeated BlkIOEntry io_serviced_recursive = 2;
diff --git a/vendor/github.com/containerd/containerd/log/context.go b/vendor/github.com/containerd/containerd/log/context.go
index 21599c4fd..37b6a7d1c 100644
--- a/vendor/github.com/containerd/containerd/log/context.go
+++ b/vendor/github.com/containerd/containerd/log/context.go
@@ -37,9 +37,17 @@ type (
 	loggerKey struct{}
 )
 
-// RFC3339NanoFixed is time.RFC3339Nano with nanoseconds padded using zeros to
-// ensure the formatted time is always the same number of characters.
-const RFC3339NanoFixed = "2006-01-02T15:04:05.000000000Z07:00"
+const (
+	// RFC3339NanoFixed is time.RFC3339Nano with nanoseconds padded using zeros to
+	// ensure the formatted time is always the same number of characters.
+	RFC3339NanoFixed = "2006-01-02T15:04:05.000000000Z07:00"
+
+	// TextFormat represents the text logging format
+	TextFormat = "text"
+
+	// JSONFormat represents the JSON logging format
+	JSONFormat = "json"
+)
 
 // WithLogger returns a new context with the provided logger. Use in
 // combination with logger.WithField(s) for great effect.
diff --git a/vendor/github.com/containerd/containerd/platforms/compare.go b/vendor/github.com/containerd/containerd/platforms/compare.go
index 3ad22a10d..c7657e186 100644
--- a/vendor/github.com/containerd/containerd/platforms/compare.go
+++ b/vendor/github.com/containerd/containerd/platforms/compare.go
@@ -16,7 +16,12 @@
 
 package platforms
 
-import specs "github.com/opencontainers/image-spec/specs-go/v1"
+import (
+	"strconv"
+	"strings"
+
+	specs "github.com/opencontainers/image-spec/specs-go/v1"
+)
 
 // MatchComparer is able to match and compare platforms to
 // filter and sort platforms.
@@ -26,103 +31,70 @@ type MatchComparer interface {
 	Less(specs.Platform, specs.Platform) bool
 }
 
-// Only returns a match comparer for a single platform
-// using default resolution logic for the platform.
-//
-// For ARMv8, will also match ARMv7, ARMv6 and ARMv5 (for 32bit runtimes)
-// For ARMv7, will also match ARMv6 and ARMv5
-// For ARMv6, will also match ARMv5
-func Only(platform specs.Platform) MatchComparer {
-	platform = Normalize(platform)
-	if platform.Architecture == "arm" {
-		if platform.Variant == "v8" {
-			return orderedPlatformComparer{
-				matchers: []Matcher{
-					&matcher{
-						Platform: platform,
-					},
-					&matcher{
-						Platform: specs.Platform{
-							Architecture: platform.Architecture,
-							OS:           platform.OS,
-							OSVersion:    platform.OSVersion,
-							OSFeatures:   platform.OSFeatures,
-							Variant:      "v7",
-						},
-					},
-					&matcher{
-						Platform: specs.Platform{
-							Architecture: platform.Architecture,
-							OS:           platform.OS,
-							OSVersion:    platform.OSVersion,
-							OSFeatures:   platform.OSFeatures,
-							Variant:      "v6",
-						},
-					},
-					&matcher{
-						Platform: specs.Platform{
-							Architecture: platform.Architecture,
-							OS:           platform.OS,
-							OSVersion:    platform.OSVersion,
-							OSFeatures:   platform.OSFeatures,
-							Variant:      "v5",
-						},
-					},
-				},
-			}
-		}
-		if platform.Variant == "v7" {
-			return orderedPlatformComparer{
-				matchers: []Matcher{
-					&matcher{
-						Platform: platform,
-					},
-					&matcher{
-						Platform: specs.Platform{
-							Architecture: platform.Architecture,
-							OS:           platform.OS,
-							OSVersion:    platform.OSVersion,
-							OSFeatures:   platform.OSFeatures,
-							Variant:      "v6",
-						},
-					},
-					&matcher{
-						Platform: specs.Platform{
-							Architecture: platform.Architecture,
-							OS:           platform.OS,
-							OSVersion:    platform.OSVersion,
-							OSFeatures:   platform.OSFeatures,
-							Variant:      "v5",
-						},
-					},
-				},
+// platformVector returns an (ordered) vector of appropriate specs.Platform
+// objects to try matching for the given platform object (see platforms.Only).
+func platformVector(platform specs.Platform) []specs.Platform {
+	vector := []specs.Platform{platform}
+
+	switch platform.Architecture {
+	case "amd64":
+		vector = append(vector, specs.Platform{
+			Architecture: "386",
+			OS:           platform.OS,
+			OSVersion:    platform.OSVersion,
+			OSFeatures:   platform.OSFeatures,
+			Variant:      platform.Variant,
+		})
+	case "arm":
+		if armVersion, err := strconv.Atoi(strings.TrimPrefix(platform.Variant, "v")); err == nil && armVersion > 5 {
+			for armVersion--; armVersion >= 5; armVersion-- {
+				vector = append(vector, specs.Platform{
+					Architecture: platform.Architecture,
+					OS:           platform.OS,
+					OSVersion:    platform.OSVersion,
+					OSFeatures:   platform.OSFeatures,
+					Variant:      "v" + strconv.Itoa(armVersion),
+				})
 			}
 		}
-		if platform.Variant == "v6" {
-			return orderedPlatformComparer{
-				matchers: []Matcher{
-					&matcher{
-						Platform: platform,
-					},
-					&matcher{
-						Platform: specs.Platform{
-							Architecture: platform.Architecture,
-							OS:           platform.OS,
-							OSVersion:    platform.OSVersion,
-							OSFeatures:   platform.OSFeatures,
-							Variant:      "v5",
-						},
-					},
-				},
-			}
+	case "arm64":
+		variant := platform.Variant
+		if variant == "" {
+			variant = "v8"
 		}
+		vector = append(vector, platformVector(specs.Platform{
+			Architecture: "arm",
+			OS:           platform.OS,
+			OSVersion:    platform.OSVersion,
+			OSFeatures:   platform.OSFeatures,
+			Variant:      variant,
+		})...)
 	}
 
-	return singlePlatformComparer{
-		Matcher: &matcher{
-			Platform: platform,
-		},
-	}
+	return vector
+}
+
+// Only returns a match comparer for a single platform
+// using default resolution logic for the platform.
+//
+// For arm/v8, will also match arm/v7, arm/v6 and arm/v5
+// For arm/v7, will also match arm/v6 and arm/v5
+// For arm/v6, will also match arm/v5
+// For amd64, will also match 386
+func Only(platform specs.Platform) MatchComparer {
+	return Ordered(platformVector(Normalize(platform))...)
+}
+
+// OnlyStrict returns a match comparer for a single platform.
+//
+// Unlike Only, OnlyStrict does not match sub platforms.
+// So, "arm/vN" will not match "arm/vM" where M < N,
+// and "amd64" will not also match "386".
+//
+// OnlyStrict matches non-canonical forms.
+// So, "arm64" matches "arm/64/v8".
+func OnlyStrict(platform specs.Platform) MatchComparer {
+	return Ordered(Normalize(platform))
 }
 
 // Ordered returns a platform MatchComparer which matches any of the platforms
@@ -153,14 +125,6 @@ func Any(platforms ...specs.Platform) MatchComparer {
 // with preference for ordering.
 var All MatchComparer = allPlatformComparer{}
 
-type singlePlatformComparer struct {
-	Matcher
-}
-
-func (c singlePlatformComparer) Less(p1, p2 specs.Platform) bool {
-	return c.Match(p1) && !c.Match(p2)
-}
-
 type orderedPlatformComparer struct {
 	matchers []Matcher
 }
diff --git a/vendor/github.com/containerd/containerd/platforms/cpuinfo.go b/vendor/github.com/containerd/containerd/platforms/cpuinfo.go
index db65a726b..4a7177e31 100644
--- a/vendor/github.com/containerd/containerd/platforms/cpuinfo.go
+++ b/vendor/github.com/containerd/containerd/platforms/cpuinfo.go
@@ -21,6 +21,7 @@ import (
 	"os"
 	"runtime"
 	"strings"
+	"sync"
 
 	"github.com/containerd/containerd/errdefs"
 	"github.com/containerd/containerd/log"
@@ -28,14 +29,18 @@ import (
 )
 
 // Present the ARM instruction set architecture, eg: v7, v8
-var cpuVariant string
+// Don't use this value directly; call cpuVariant() instead.
+var cpuVariantValue string
 
-func init() {
-	if isArmArch(runtime.GOARCH) {
-		cpuVariant = getCPUVariant()
-	} else {
-		cpuVariant = ""
-	}
+var cpuVariantOnce sync.Once
+
+func cpuVariant() string {
+	cpuVariantOnce.Do(func() {
+		if isArmArch(runtime.GOARCH) {
+			cpuVariantValue = getCPUVariant()
+		}
+	})
+	return cpuVariantValue
 }
 
 // For Linux, the kernel has already detected the ABI, ISA and Features.
@@ -96,14 +101,18 @@ func getCPUVariant() string {
 		return ""
 	}
 
+	// handle edge case for Raspberry Pi ARMv6 devices (which due to a kernel quirk, report "CPU architecture: 7")
+	// https://www.raspberrypi.org/forums/viewtopic.php?t=12614
+	if runtime.GOARCH == "arm" && variant == "7" {
+		model, err := getCPUInfo("model name")
+		if err == nil && strings.HasPrefix(strings.ToLower(model), "armv6-compatible") {
+			variant = "6"
+		}
+	}
+
 	switch strings.ToLower(variant) {
 	case "8", "aarch64":
-		// special case: if running a 32-bit userspace on aarch64, the variant should be "v7"
-		if runtime.GOARCH == "arm" {
-			variant = "v7"
-		} else {
-			variant = "v8"
-		}
+		variant = "v8"
 	case "7", "7m", "?(12)", "?(13)", "?(14)", "?(15)", "?(16)", "?(17)":
 		variant = "v7"
 	case "6", "6tej":
diff --git a/vendor/github.com/containerd/containerd/platforms/defaults.go b/vendor/github.com/containerd/containerd/platforms/defaults.go
index a14d80e58..cb77fbc9f 100644
--- a/vendor/github.com/containerd/containerd/platforms/defaults.go
+++ b/vendor/github.com/containerd/containerd/platforms/defaults.go
@@ -33,6 +33,11 @@ func DefaultSpec() specs.Platform {
 		OS:           runtime.GOOS,
 		Architecture: runtime.GOARCH,
 		// The Variant field will be empty if arch != ARM.
-		Variant: cpuVariant,
+		Variant: cpuVariant(),
 	}
 }
+
+// DefaultStrict returns strict form of Default.
+func DefaultStrict() MatchComparer {
+	return OnlyStrict(DefaultSpec())
+}
diff --git a/vendor/github.com/containerd/containerd/platforms/defaults_windows.go b/vendor/github.com/containerd/containerd/platforms/defaults_windows.go
index 0defbd36c..58713aa5f 100644
--- a/vendor/github.com/containerd/containerd/platforms/defaults_windows.go
+++ b/vendor/github.com/containerd/containerd/platforms/defaults_windows.go
@@ -19,6 +19,8 @@
 package platforms
 
 import (
+	"runtime"
+
 	specs "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
@@ -26,6 +28,6 @@ import (
 func Default() MatchComparer {
 	return Ordered(DefaultSpec(), specs.Platform{
 		OS:           "linux",
-		Architecture: "amd64",
+		Architecture: runtime.GOARCH,
 	})
 }
diff --git a/vendor/github.com/containerd/containerd/platforms/platforms.go b/vendor/github.com/containerd/containerd/platforms/platforms.go
index 77d3f184e..088bdea05 100644
--- a/vendor/github.com/containerd/containerd/platforms/platforms.go
+++ b/vendor/github.com/containerd/containerd/platforms/platforms.go
@@ -189,8 +189,8 @@ func Parse(specifier string) (specs.Platform, error) {
 		if isKnownOS(p.OS) {
 			// picks a default architecture
 			p.Architecture = runtime.GOARCH
-			if p.Architecture == "arm" && cpuVariant != "v7" {
-				p.Variant = cpuVariant
+			if p.Architecture == "arm" && cpuVariant() != "v7" {
+				p.Variant = cpuVariant()
 			}
 
 			return p, nil
diff --git a/vendor/github.com/containerd/containerd/sys/oom_unix.go b/vendor/github.com/containerd/containerd/sys/oom_unix.go
index d49d5bc8d..c381e1a7e 100644
--- a/vendor/github.com/containerd/containerd/sys/oom_unix.go
+++ b/vendor/github.com/containerd/containerd/sys/oom_unix.go
@@ -26,8 +26,12 @@ import (
 	"strings"
 )
 
-// OOMScoreMaxKillable is the maximum score keeping the process killable by the oom killer
-const OOMScoreMaxKillable = -999
+const (
+	// OOMScoreMaxKillable is the maximum score keeping the process killable by the oom killer
+	OOMScoreMaxKillable = -999
+	// OOMScoreAdjMax is from OOM_SCORE_ADJ_MAX https://github.com/torvalds/linux/blob/master/include/uapi/linux/oom.h
+	OOMScoreAdjMax = 1000
+)
 
 // SetOOMScore sets the oom score for the provided pid
 func SetOOMScore(pid, score int) error {
diff --git a/vendor/github.com/containerd/containerd/sys/oom_windows.go b/vendor/github.com/containerd/containerd/sys/oom_windows.go
index a917ba635..215c171f6 100644
--- a/vendor/github.com/containerd/containerd/sys/oom_windows.go
+++ b/vendor/github.com/containerd/containerd/sys/oom_windows.go
@@ -16,6 +16,11 @@
 
 package sys
 
+const (
+	// OOMScoreAdjMax is not implemented on Windows
+	OOMScoreAdjMax = 0
+)
+
 // SetOOMScore sets the oom score for the process
 //
 // Not implemented on Windows
diff --git a/vendor/github.com/containerd/containerd/sys/stat_bsd.go b/vendor/github.com/containerd/containerd/sys/stat_bsd.go
index b9c95d90d..4f03cd6cb 100644
--- a/vendor/github.com/containerd/containerd/sys/stat_bsd.go
+++ b/vendor/github.com/containerd/containerd/sys/stat_bsd.go
@@ -1,4 +1,4 @@
-// +build darwin freebsd
+// +build darwin freebsd netbsd
 
 /*
    Copyright The containerd Authors.
diff --git a/vendor/github.com/containerd/containerd/sys/stat_openbsd.go b/vendor/github.com/containerd/containerd/sys/stat_openbsd.go
new file mode 100644
index 000000000..ec3b9df69
--- /dev/null
+++ b/vendor/github.com/containerd/containerd/sys/stat_openbsd.go
@@ -0,0 +1,45 @@
+// +build openbsd
+
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package sys
+
+import (
+	"syscall"
+	"time"
+)
+
+// StatAtime returns the Atim
+func StatAtime(st *syscall.Stat_t) syscall.Timespec {
+	return st.Atim
+}
+
+// StatCtime returns the Ctim
+func StatCtime(st *syscall.Stat_t) syscall.Timespec {
+	return st.Ctim
+}
+
+// StatMtime returns the Mtim
+func StatMtime(st *syscall.Stat_t) syscall.Timespec {
+	return st.Mtim
+}
+
+// StatATimeAsTime returns st.Atim as a time.Time
+func StatATimeAsTime(st *syscall.Stat_t) time.Time {
+	// The int64 conversions ensure the line compiles for 32-bit systems as well.
+	return time.Unix(int64(st.Atim.Sec), int64(st.Atim.Nsec)) // nolint: unconvert
+}
diff --git a/vendor/github.com/containerd/continuity/AUTHORS b/vendor/github.com/containerd/continuity/AUTHORS
index 4043394cc..376ceb93d 100644
--- a/vendor/github.com/containerd/continuity/AUTHORS
+++ b/vendor/github.com/containerd/continuity/AUTHORS
@@ -1,16 +1,40 @@
 Aaron Lehmann <aaron.lehmann@docker.com>
 Akash Gupta <akagup@microsoft.com>
+Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
 Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
+Akihiro Suda <suda.kyoto@gmail.com>
 Andrew Pennebaker <apennebaker@datapipe.com>
 Brandon Philips <brandon.philips@coreos.com>
+Brian Goff <cpuguy83@gmail.com>
 Christopher Jones <tophj@linux.vnet.ibm.com>
 Daniel, Dao Quang Minh <dqminh89@gmail.com>
+Darren Stahl <darst@microsoft.com>
+Derek McGowan <derek@mcg.dev>
 Derek McGowan <derek@mcgstyle.net>
 Edward Pilatowicz <edward.pilatowicz@oracle.com>
 Ian Campbell <ijc@docker.com>
+Ivan Markin <sw@nogoegst.net>
 Justin Cormack <justin.cormack@docker.com>
 Justin Cummins <sul3n3t@gmail.com>
+Kasper Fabæch Brandt <poizan@poizan.dk>
+Kir Kolyshkin <kolyshkin@gmail.com>
+Michael Crosby <crosbymichael@gmail.com>
+Michael Crosby <michael@thepasture.io>
+Michael Wan <zirenwan@gmail.com>
+Mike Brown <brownwm@us.ibm.com>
+Niels de Vos <ndevos@redhat.com>
 Phil Estes <estesp@gmail.com>
+Phil Estes <estesp@linux.vnet.ibm.com>
+Samuel Karp <me@samuelkarp.com>
+Sam Whited <sam@samwhited.com>
+Sebastiaan van Stijn <github@gone.nl>
+Shengjing Zhu <zhsj@debian.org>
 Stephen J Day <stephen.day@docker.com>
+Tibor Vass <tibor@docker.com>
 Tobias Klauser <tklauser@distanz.ch>
+Tom Faulhaber <tffaulha@amazon.com>
 Tonis Tiigi <tonistiigi@gmail.com>
+Trevor Porter <trkporter@ucdavis.edu>
+Wei Fu <fuweid89@gmail.com>
+Wilbert van de Ridder <wilbert.ridder@gmail.com>
+Xiaodong Ye <xiaodongy@vmware.com>
diff --git a/vendor/github.com/containerd/continuity/fs/copy_darwinopenbsdsolaris.go b/vendor/github.com/containerd/continuity/fs/copy_darwinopenbsdsolaris.go
new file mode 100644
index 000000000..92ccacf9a
--- /dev/null
+++ b/vendor/github.com/containerd/continuity/fs/copy_darwinopenbsdsolaris.go
@@ -0,0 +1,40 @@
+// +build darwin openbsd solaris
+
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package fs
+
+import (
+	"os"
+	"syscall"
+
+	"github.com/pkg/errors"
+	"golang.org/x/sys/unix"
+)
+
+func copyDevice(dst string, fi os.FileInfo) error {
+	st, ok := fi.Sys().(*syscall.Stat_t)
+	if !ok {
+		return errors.New("unsupported stat type")
+	}
+	return unix.Mknod(dst, uint32(fi.Mode()), int(st.Rdev))
+}
+
+func utimesNano(name string, atime, mtime syscall.Timespec) error {
+	timespec := []syscall.Timespec{atime, mtime}
+	return syscall.UtimesNano(name, timespec)
+}
diff --git a/vendor/github.com/containerd/continuity/fs/copy_freebsd.go b/vendor/github.com/containerd/continuity/fs/copy_freebsd.go
new file mode 100644
index 000000000..4b116c95e
--- /dev/null
+++ b/vendor/github.com/containerd/continuity/fs/copy_freebsd.go
@@ -0,0 +1,42 @@
+// +build freebsd
+
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package fs
+
+import (
+	"os"
+	"syscall"
+
+	"github.com/pkg/errors"
+	"golang.org/x/sys/unix"
+)
+
+func copyDevice(dst string, fi os.FileInfo) error {
+	st, ok := fi.Sys().(*syscall.Stat_t)
+	if !ok {
+		return errors.New("unsupported stat type")
+	}
+	return unix.Mknod(dst, uint32(fi.Mode()), st.Rdev)
+}
+
+func utimesNano(name string, atime, mtime syscall.Timespec) error {
+	at := unix.NsecToTimespec(atime.Nano())
+	mt := unix.NsecToTimespec(mtime.Nano())
+	utimes := [2]unix.Timespec{at, mt}
+	return unix.UtimesNanoAt(unix.AT_FDCWD, name, utimes[0:], unix.AT_SYMLINK_NOFOLLOW)
+}
diff --git a/vendor/github.com/containerd/continuity/fs/copy_unix.go b/vendor/github.com/containerd/continuity/fs/copy_unix.go
index a5de89261..dfd857aaa 100644
--- a/vendor/github.com/containerd/continuity/fs/copy_unix.go
+++ b/vendor/github.com/containerd/continuity/fs/copy_unix.go
@@ -25,7 +25,6 @@ import (
 
 	"github.com/containerd/continuity/sysx"
 	"github.com/pkg/errors"
-	"golang.org/x/sys/unix"
 )
 
 func copyFileInfo(fi os.FileInfo, name string) error {
@@ -53,8 +52,7 @@ func copyFileInfo(fi os.FileInfo, name string) error {
 		}
 	}
 
-	timespec := []syscall.Timespec{StatAtime(st), StatMtime(st)}
-	if err := syscall.UtimesNano(name, timespec); err != nil {
+	if err := utimesNano(name, StatAtime(st), StatMtime(st)); err != nil {
 		return errors.Wrapf(err, "failed to utime %s", name)
 	}
 
@@ -102,11 +100,3 @@ func copyXAttrs(dst, src string, xeh XAttrErrorHandler) error {
 
 	return nil
 }
-
-func copyDevice(dst string, fi os.FileInfo) error {
-	st, ok := fi.Sys().(*syscall.Stat_t)
-	if !ok {
-		return errors.New("unsupported stat type")
-	}
-	return unix.Mknod(dst, uint32(fi.Mode()), int(st.Rdev))
-}
diff --git a/vendor/github.com/containerd/continuity/fs/du_unix.go b/vendor/github.com/containerd/continuity/fs/du_unix.go
index e22ffbea3..9da43d1bc 100644
--- a/vendor/github.com/containerd/continuity/fs/du_unix.go
+++ b/vendor/github.com/containerd/continuity/fs/du_unix.go
@@ -25,6 +25,14 @@ import (
 	"syscall"
 )
 
+// blocksUnitSize is the unit used by `st_blocks` in `stat` in bytes.
+// See https://man7.org/linux/man-pages/man2/stat.2.html
+//   st_blocks
+//     This field indicates the number of blocks allocated to the
+//     file, in 512-byte units.  (This may be smaller than
+//     st_size/512 when the file has holes.)
+const blocksUnitSize = 512
+
 type inode struct {
 	// TODO(stevvooe): Can probably reduce memory usage by not tracking
 	// device, but we can leave this right for now.
@@ -33,9 +41,9 @@ type inode struct {
 
 func newInode(stat *syscall.Stat_t) inode {
 	return inode{
-		// Dev is uint32 on darwin/bsd, uint64 on linux/solaris
+		// Dev is uint32 on darwin/bsd, uint64 on linux/solaris/freebsd
 		dev: uint64(stat.Dev), // nolint: unconvert
-		// Ino is uint32 on bsd, uint64 on darwin/linux/solaris
+		// Ino is uint32 on bsd, uint64 on darwin/linux/solaris/freebsd
 		ino: uint64(stat.Ino), // nolint: unconvert
 	}
 }
@@ -59,10 +67,11 @@ func diskUsage(ctx context.Context, roots ...string) (Usage, error) {
 			default:
 			}
 
-			inoKey := newInode(fi.Sys().(*syscall.Stat_t))
+			stat := fi.Sys().(*syscall.Stat_t)
+			inoKey := newInode(stat)
 			if _, ok := inodes[inoKey]; !ok {
 				inodes[inoKey] = struct{}{}
-				size += fi.Size()
+				size += stat.Blocks * blocksUnitSize
 			}
 
 			return nil
@@ -89,10 +98,11 @@ func diffUsage(ctx context.Context, a, b string) (Usage, error) {
 		}
 
 		if kind == ChangeKindAdd || kind == ChangeKindModify {
-			inoKey := newInode(fi.Sys().(*syscall.Stat_t))
+			stat := fi.Sys().(*syscall.Stat_t)
+			inoKey := newInode(stat)
 			if _, ok := inodes[inoKey]; !ok {
 				inodes[inoKey] = struct{}{}
-				size += fi.Size()
+				size += stat.Blocks * blocksUnitSize
 			}
 
 			return nil
diff --git a/vendor/github.com/containerd/continuity/fs/path.go b/vendor/github.com/containerd/continuity/fs/path.go
index 8863caa9d..c26be7989 100644
--- a/vendor/github.com/containerd/continuity/fs/path.go
+++ b/vendor/github.com/containerd/continuity/fs/path.go
@@ -117,15 +117,13 @@ func sameFile(f1, f2 *currentPath) (bool, error) {
 		// If the timestamp may have been truncated in both of the
 		// files, check content of file to determine difference
 		if t1.Nanosecond() == 0 && t2.Nanosecond() == 0 {
-			var eq bool
 			if (f1.f.Mode() & os.ModeSymlink) == os.ModeSymlink {
-				eq, err = compareSymlinkTarget(f1.fullPath, f2.fullPath)
-			} else if f1.f.Size() > 0 {
-				eq, err = compareFileContent(f1.fullPath, f2.fullPath)
+				return compareSymlinkTarget(f1.fullPath, f2.fullPath)
 			}
-			if err != nil || !eq {
-				return eq, err
+			if f1.f.Size() == 0 { // if file sizes are zero length, the files are the same by definition
+				return true, nil
 			}
+			return compareFileContent(f1.fullPath, f2.fullPath)
 		} else if t1.Nanosecond() != t2.Nanosecond() {
 			return false, nil
 		}
diff --git a/vendor/github.com/containerd/continuity/sysx/xattr_unsupported.go b/vendor/github.com/containerd/continuity/sysx/xattr_unsupported.go
index c9ef3a1d2..f8fa8c63f 100644
--- a/vendor/github.com/containerd/continuity/sysx/xattr_unsupported.go
+++ b/vendor/github.com/containerd/continuity/sysx/xattr_unsupported.go
@@ -23,7 +23,7 @@ import (
 	"runtime"
 )
 
-var unsupported = errors.New("extended attributes unsupported on " + runtime.GOOS)
+var errUnsupported = errors.New("extended attributes unsupported on " + runtime.GOOS)
 
 // Listxattr calls syscall listxattr and reads all content
 // and returns a string array
@@ -33,17 +33,17 @@ func Listxattr(path string) ([]string, error) {
 
 // Removexattr calls syscall removexattr
 func Removexattr(path string, attr string) (err error) {
-	return unsupported
+	return errUnsupported
 }
 
 // Setxattr calls syscall setxattr
 func Setxattr(path string, attr string, data []byte, flags int) (err error) {
-	return unsupported
+	return errUnsupported
 }
 
 // Getxattr calls syscall getxattr
 func Getxattr(path, attr string) ([]byte, error) {
-	return []byte{}, unsupported
+	return []byte{}, errUnsupported
 }
 
 // LListxattr lists xattrs, not following symlinks
@@ -53,12 +53,12 @@ func LListxattr(path string) ([]string, error) {
 
 // LRemovexattr removes an xattr, not following symlinks
 func LRemovexattr(path string, attr string) (err error) {
-	return unsupported
+	return errUnsupported
 }
 
 // LSetxattr sets an xattr, not following symlinks
 func LSetxattr(path string, attr string, data []byte, flags int) (err error) {
-	return unsupported
+	return errUnsupported
 }
 
 // LGetxattr gets an xattr, not following symlinks