Merge release-20201030.0-79-g62db1fad2 (automated)

2 files changed, 9 insertions, 1 deletions

diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go
index 1ecf76b2b..2cdcdfc1f 100644
--- a/pkg/sentry/kernel/kernel.go
+++ b/pkg/sentry/kernel/kernel.go
@@ -1359,6 +1359,13 @@ func (k *Kernel) SendContainerSignal(cid string, info *arch.SignalInfo) error {
 // not have meaningful trace data. Rebuilding here ensures that we can do so
 // after tracing has been enabled.
 func (k *Kernel) RebuildTraceContexts() {
+	// We need to pause all task goroutines because Task.rebuildTraceContext()
+	// replaces Task.traceContext and Task.traceTask, which are
+	// task-goroutine-exclusive (i.e. the task goroutine assumes that it can
+	// access them without synchronization) for performance.
+	k.Pause()
+	defer k.Unpause()
+
 	k.extMu.Lock()
 	defer k.extMu.Unlock()
 	k.tasks.mu.RLock()
diff --git a/pkg/sentry/kernel/task_log.go b/pkg/sentry/kernel/task_log.go
index 7591eaace..c70e5e6ce 100644
--- a/pkg/sentry/kernel/task_log.go
+++ b/pkg/sentry/kernel/task_log.go
@@ -19,6 +19,7 @@ import (
 	"runtime/trace"
 	"sort"
 
+	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/usermem"
 )
@@ -215,7 +216,7 @@ func (t *Task) rebuildTraceContext(tid ThreadID) {
 	// arbitrarily large (in general it won't be, especially for cases
 	// where we're collecting a brief profile), so using the TID is a
 	// reasonable compromise in this case.
-	t.traceContext, t.traceTask = trace.NewTask(t, fmt.Sprintf("tid:%d", tid))
+	t.traceContext, t.traceTask = trace.NewTask(context.Background(), fmt.Sprintf("tid:%d", tid))
 }
 
 // traceCloneEvent is called when a new task is spawned.