Merge release-20200928.0-72-g6bad4851d (automated)

3 files changed, 21 insertions, 0 deletions

diff --git a/pkg/sentry/mm/mm.go b/pkg/sentry/mm/mm.go
index 43567b92c..92cc87d84 100644
--- a/pkg/sentry/mm/mm.go
+++ b/pkg/sentry/mm/mm.go
@@ -243,6 +243,12 @@ type MemoryManager struct {
 	//
 	// membarrierPrivateEnabled is accessed using atomic memory operations.
 	membarrierPrivateEnabled uint32
+
+	// membarrierRSeqEnabled is non-zero if EnableMembarrierRSeq has previously
+	// been called.
+	//
+	// membarrierRSeqEnabled is accessed using atomic memory operations.
+	membarrierRSeqEnabled uint32
 }
 
 // vma represents a virtual memory area.
diff --git a/pkg/sentry/mm/mm_state_autogen.go b/pkg/sentry/mm/mm_state_autogen.go
index 1636e5235..1fe9dfd7f 100644
--- a/pkg/sentry/mm/mm_state_autogen.go
+++ b/pkg/sentry/mm/mm_state_autogen.go
@@ -316,6 +316,7 @@ func (m *MemoryManager) StateFields() []string {
 		"sleepForActivation",
 		"vdsoSigReturnAddr",
 		"membarrierPrivateEnabled",
+		"membarrierRSeqEnabled",
 	}
 }
 
@@ -350,6 +351,7 @@ func (m *MemoryManager) StateSave(stateSinkObject state.Sink) {
 	stateSinkObject.Save(20, &m.sleepForActivation)
 	stateSinkObject.Save(21, &m.vdsoSigReturnAddr)
 	stateSinkObject.Save(22, &m.membarrierPrivateEnabled)
+	stateSinkObject.Save(23, &m.membarrierRSeqEnabled)
 }
 
 func (m *MemoryManager) StateLoad(stateSourceObject state.Source) {
@@ -376,6 +378,7 @@ func (m *MemoryManager) StateLoad(stateSourceObject state.Source) {
 	stateSourceObject.Load(20, &m.sleepForActivation)
 	stateSourceObject.Load(21, &m.vdsoSigReturnAddr)
 	stateSourceObject.Load(22, &m.membarrierPrivateEnabled)
+	stateSourceObject.Load(23, &m.membarrierRSeqEnabled)
 	stateSourceObject.AfterLoad(m.afterLoad)
 }
 
diff --git a/pkg/sentry/mm/syscalls.go b/pkg/sentry/mm/syscalls.go
index 0a66b1cdd..675efdc7c 100644
--- a/pkg/sentry/mm/syscalls.go
+++ b/pkg/sentry/mm/syscalls.go
@@ -1287,3 +1287,15 @@ func (mm *MemoryManager) EnableMembarrierPrivate() {
 func (mm *MemoryManager) IsMembarrierPrivateEnabled() bool {
 	return atomic.LoadUint32(&mm.membarrierPrivateEnabled) != 0
 }
+
+// EnableMembarrierRSeq causes future calls to IsMembarrierRSeqEnabled to
+// return true.
+func (mm *MemoryManager) EnableMembarrierRSeq() {
+	atomic.StoreUint32(&mm.membarrierRSeqEnabled, 1)
+}
+
+// IsMembarrierRSeqEnabled returns true if mm.EnableMembarrierRSeq() has
+// previously been called.
+func (mm *MemoryManager) IsMembarrierRSeqEnabled() bool {
+	return atomic.LoadUint32(&mm.membarrierRSeqEnabled) != 0
+}