Merge remote-tracking branch 'origin/main' into leak-stacks

Author: zenhack

rpc/answer.go

@@ -98,7 +98,7 @@ func errorAnswer(c *Conn, id answerID, err error) *answer {
 // newReturn creates a new Return message. The returned Releaser will release the message when
 // all references to it are dropped; the caller is responsible for one reference. This will not
 // happen before the message is sent, as the returned send function retains a reference.
-func (c *Conn) newReturn(ctx context.Context) (_ rpccp.Return, sendMsg func(), _ *rc.Releaser, _ error) {
+func (c *Conn) newReturn() (_ rpccp.Return, sendMsg func(), _ *rc.Releaser, _ error) {
 	outMsg, err := c.transport.NewMessage()
 	if err != nil {
 		return rpccp.Return{}, nil, nil, rpcerr.Failedf("create return: %w", err)

rpc/rpc.go

@@ -72,8 +72,11 @@ type Conn struct {
 	er           errReporter
 	abortTimeout time.Duration
 
-	// bgctx is a Context that is canceled when shutdown starts.
+	// bgctx is a Context that is canceled when shutdown starts. Note
+	// that it's parent is context.Background(), so we can rely on this
+	// being the *only* time it will be canceled.
 	bgctx context.Context
+
 	// tasks block shutdown.
 	tasks  sync.WaitGroup
 	closed chan struct{} // closed when shutdown() returns
@@ -619,7 +622,7 @@ func (c *Conn) handleBootstrap(ctx context.Context, id answerID) error {
 	)
 
 	syncutil.Without(&c.lk, func() {
-		ans.ret, ans.sendMsg, ans.msgReleaser, err = c.newReturn(ctx)
+		ans.ret, ans.sendMsg, ans.msgReleaser, err = c.newReturn()
 		if err == nil {
 			ans.ret.SetAnswerId(uint32(id))
 			ans.ret.SetReleaseParamCaps(false)
@@ -694,7 +697,7 @@ func (c *Conn) handleCall(ctx context.Context, call rpccp.Call, releaseCall capn
 
 	// Create return message.
 	c.lk.Unlock()
-	ret, send, retReleaser, err := c.newReturn(ctx)
+	ret, send, retReleaser, err := c.newReturn()
 	if err != nil {
 		err = rpcerr.Annotate(err, "incoming call")
 		syncutil.With(&c.lk, func() {