diff --git a/cmd/buildctl/build.go b/cmd/buildctl/build.go
index 327b66f1..46830c8f 100644
--- a/cmd/buildctl/build.go
+++ b/cmd/buildctl/build.go
@@ -154,7 +154,7 @@ func buildAction(clicontext *cli.Context) error {
 		logrus.Infof("tracing logs to %s", traceFile.Name())
 	}
 
-	attachable := []session.Attachable{authprovider.NewDockerAuthProvider()}
+	attachable := []session.Attachable{authprovider.NewDockerAuthProvider(os.Stderr)}
 
 	if ssh := clicontext.StringSlice("ssh"); len(ssh) > 0 {
 		configs, err := build.ParseSSH(ssh)
diff --git a/session/auth/authprovider/authprovider.go b/session/auth/authprovider/authprovider.go
index 7df33cca..a7eb6f22 100644
--- a/session/auth/authprovider/authprovider.go
+++ b/session/auth/authprovider/authprovider.go
@@ -2,7 +2,7 @@ package authprovider
 
 import (
 	"context"
-	"io/ioutil"
+	"io"
 	"sync"
 
 	"github.com/docker/cli/cli/config"
@@ -12,9 +12,9 @@ import (
 	"google.golang.org/grpc"
 )
 
-func NewDockerAuthProvider() session.Attachable {
+func NewDockerAuthProvider(stderr io.Writer) session.Attachable {
 	return &authProvider{
-		config: config.LoadDefaultConfigFile(ioutil.Discard),
+		config: config.LoadDefaultConfigFile(stderr),
 	}
 }