diff --git a/terraform/context_input_test.go b/terraform/context_input_test.go
index 750db918a5..8c20998551 100644
--- a/terraform/context_input_test.go
+++ b/terraform/context_input_test.go
@@ -1,6 +1,7 @@
 package terraform
 
 import (
+	"errors"
 	"reflect"
 	"strings"
 	"sync"
@@ -211,16 +212,25 @@ func TestContext2Input_providerOnce(t *testing.T) {
 	count := 0
 	p.InputFn = func(i UIInput, c *ResourceConfig) (*ResourceConfig, error) {
 		count++
-		return nil, nil
+		_, set := c.Config["from_input"]
+
+		if count == 1 {
+			if set {
+				return nil, errors.New("from_input should not be set")
+			}
+			c.Config["from_input"] = "x"
+		}
+
+		if count > 1 && !set {
+			return nil, errors.New("from_input should be set")
+		}
+
+		return c, nil
 	}
 
 	if err := ctx.Input(InputModeStd); err != nil {
 		t.Fatalf("err: %s", err)
 	}
-
-	if count != 1 {
-		t.Fatalf("should only be called once: %d", count)
-	}
 }
 
 func TestContext2Input_providerId(t *testing.T) {
diff --git a/terraform/eval_provider.go b/terraform/eval_provider.go
index e42f1c0dc3..328d72b5ea 100644
--- a/terraform/eval_provider.go
+++ b/terraform/eval_provider.go
@@ -99,12 +99,8 @@ type EvalInputProvider struct {
 }
 
 func (n *EvalInputProvider) Eval(ctx EvalContext) (interface{}, error) {
-	// If we already configured this provider, then don't do this again
-	if v := ctx.ProviderInput(n.Name); v != nil {
-		return nil, nil
-	}
-
 	rc := *n.Config
+	orig := rc.DeepCopy()
 
 	// Wrap the input into a namespace
 	input := &PrefixUIInput{
@@ -121,27 +117,19 @@ func (n *EvalInputProvider) Eval(ctx EvalContext) (interface{}, error) {
 			"Error configuring %s: %s", n.Name, err)
 	}
 
-	// Set the input that we received so that child modules don't attempt
-	// to ask for input again.
+	// We only store values that have changed through Input.
+	// The goal is to cache cache input responses, not to provide a complete
+	// config for other providers.
+	confMap := make(map[string]interface{})
 	if config != nil && len(config.Config) > 0 {
-		// This repository of provider input results on the context doesn't
-		// retain config.ComputedKeys, so we need to filter those out here
-		// in order that later users of this data won't try to use the unknown
-		// value placeholder as if it were a literal value. This map is just
-		// of known values we've been able to complete so far; dynamic stuff
-		// will be merged in by EvalBuildProviderConfig on subsequent
-		// (post-input) walks.
-		confMap := config.Config
-		if config.ComputedKeys != nil {
-			for _, key := range config.ComputedKeys {
-				delete(confMap, key)
+		// any values that weren't in the original ResourcConfig will be cached
+		for k, v := range config.Config {
+			if _, ok := orig.Config[k]; !ok {
+				confMap[k] = v
 			}
 		}
-
-		ctx.SetProviderInput(n.Name, confMap)
-	} else {
-		ctx.SetProviderInput(n.Name, map[string]interface{}{})
 	}
+	ctx.SetProviderInput(n.Name, confMap)
 
 	return nil, nil
 }
diff --git a/terraform/eval_provider_test.go b/terraform/eval_provider_test.go
index 000dc51287..cca02a76b4 100644
--- a/terraform/eval_provider_test.go
+++ b/terraform/eval_provider_test.go
@@ -137,9 +137,7 @@ func TestEvalInputProvider(t *testing.T) {
 			}
 
 			rawConfig, err := config.NewRawConfig(map[string]interface{}{
-				"set_in_config": "input",
-				"set_by_input":  "input",
-				"computed":      "fake_computed",
+				"set_by_input": "input",
 			})
 			if err != nil {
 				return nil, err
@@ -152,7 +150,8 @@ func TestEvalInputProvider(t *testing.T) {
 	}
 	ctx := &MockEvalContext{ProviderProvider: provider}
 	rawConfig, err := config.NewRawConfig(map[string]interface{}{
-		"mock_config": "mock",
+		"mock_config":   "mock",
+		"set_in_config": "input",
 	})
 	if err != nil {
 		t.Fatalf("NewRawConfig failed: %s", err)
@@ -182,12 +181,12 @@ func TestEvalInputProvider(t *testing.T) {
 	}
 
 	inputCfg := ctx.SetProviderInputConfig
+
+	// we should only have the value that was set during Input
 	want := map[string]interface{}{
-		"set_in_config": "input",
-		"set_by_input":  "input",
-		// "computed" is omitted because it value isn't known at input time
+		"set_by_input": "input",
 	}
 	if !reflect.DeepEqual(inputCfg, want) {
-		t.Errorf("got incorrect input config %#v; want %#v", inputCfg, want)
+		t.Errorf("got incorrect input config:\n%#v\nwant:\n%#v", inputCfg, want)
 	}
 }