diff --git a/solver/scheduler.go b/solver/scheduler.go
index 8de4d694e4b4..d56b06c9f3eb 100644
--- a/solver/scheduler.go
+++ b/solver/scheduler.go
@@ -351,7 +351,9 @@ type pipeFactory struct {
 func (pf *pipeFactory) NewInputRequest(ee Edge, req *edgeRequest) pipe.Receiver {
 	target := pf.s.ef.getEdge(ee)
 	if target == nil {
-		panic("failed to get edge") // TODO: return errored pipe
+		return pf.NewFuncRequest(func(_ context.Context) (interface{}, error) {
+			return req, errors.Errorf("failed to get edge: inconsistent graph state")
+		})
 	}
 	p := pf.s.newPipe(target, pf.e, pipe.Request{Payload: req})
 	if debugScheduler {