remove ReallyCrashForTesting and cleaned up some references to HandleCrash behavior

cmd/kubelet/app/options/options.go

@@ -54,9 +54,6 @@ type KubeletFlags struct {
 	KubeConfig          string
 	BootstrapKubeconfig string
 
-	// Crash immediately, rather than eating panics.
-	ReallyCrashForTesting bool
-
 	// HostnameOverride is the hostname used to identify the kubelet instead
 	// of the actual hostname.
 	HostnameOverride string
@@ -352,8 +349,6 @@ func (f *KubeletFlags) AddFlags(mainfs *pflag.FlagSet) {
 	fs.MarkDeprecated("non-masquerade-cidr", "will be removed in a future version")
 	fs.BoolVar(&f.KeepTerminatedPodVolumes, "keep-terminated-pod-volumes", f.KeepTerminatedPodVolumes, "Keep terminated pod volumes mounted to the node after the pod terminates.  Can be useful for debugging volume related issues.")
 	fs.MarkDeprecated("keep-terminated-pod-volumes", "will be removed in a future version")
-	fs.BoolVar(&f.ReallyCrashForTesting, "really-crash-for-testing", f.ReallyCrashForTesting, "If true, when panics occur crash. Intended for testing.")
-	fs.MarkDeprecated("really-crash-for-testing", "will be removed in a future version.")
 	fs.StringVar(&f.ExperimentalMounterPath, "experimental-mounter-path", f.ExperimentalMounterPath, "[Experimental] Path of mounter binary. Leave empty to use the default mount.")
 	fs.MarkDeprecated("experimental-mounter-path", "will be removed in 1.23. in favor of using CSI.")
 	fs.BoolVar(&f.ExperimentalCheckNodeCapabilitiesBeforeMount, "experimental-check-node-capabilities-before-mount", f.ExperimentalCheckNodeCapabilitiesBeforeMount, "[Experimental] if set true, the kubelet will check the underlying node for required components (binaries, etc.) before performing the mount")

cmd/kubelet/app/server.go

@@ -45,7 +45,6 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/types"
 	utilnet "k8s.io/apimachinery/pkg/util/net"
-	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/wait"
 	genericapiserver "k8s.io/apiserver/pkg/server"
@@ -791,8 +790,6 @@ func run(ctx context.Context, s *options.KubeletServer, kubeDeps *kubelet.Depend
 		}
 	}
 
-	utilruntime.ReallyCrash = s.ReallyCrashForTesting
-
 	// TODO(vmarmol): Do this through container config.
 	oomAdjuster := kubeDeps.OOMAdjuster
 	if err := oomAdjuster.ApplyOOMScoreAdj(0, int(s.OOMScoreAdj)); err != nil {

pkg/kubelet/kubelet_test.go

@@ -39,7 +39,6 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/types"
-	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/client-go/kubernetes/fake"
@@ -87,7 +86,6 @@ import (
 )
 
 func init() {
-	utilruntime.ReallyCrash = true
 }
 
 const (

pkg/kubelet/prober/prober_manager_test.go

@@ -25,7 +25,6 @@ import (
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
-	"k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/wait"
 	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
@@ -34,7 +33,6 @@ import (
 )
 
 func init() {
-	runtime.ReallyCrash = true
 }
 
 var defaultProbe = &v1.Probe{

pkg/kubelet/prober/worker_test.go

@@ -23,20 +23,16 @@ import (
 
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/client-go/kubernetes/fake"
-	"k8s.io/client-go/tools/record"
 	kubepod "k8s.io/kubernetes/pkg/kubelet/pod"
 	"k8s.io/kubernetes/pkg/kubelet/prober/results"
 	"k8s.io/kubernetes/pkg/kubelet/status"
 	statustest "k8s.io/kubernetes/pkg/kubelet/status/testing"
 	"k8s.io/kubernetes/pkg/probe"
-	"k8s.io/utils/exec"
 )
 
 func init() {
-	runtime.ReallyCrash = true
 }
 
 func TestDoProbe(t *testing.T) {
@@ -296,27 +292,6 @@ func TestCleanUp(t *testing.T) {
 	}
 }
 
-func TestHandleCrash(t *testing.T) {
-	runtime.ReallyCrash = false // Test that we *don't* really crash.
-
-	m := newTestManager()
-	w := newTestWorker(m, readiness, v1.Probe{})
-	m.statusManager.SetPodStatus(w.pod, getTestRunningStatus())
-
-	expectContinue(t, w, w.doProbe(), "Initial successful probe.")
-	expectResult(t, w, results.Success, "Initial successful probe.")
-
-	// Prober starts crashing.
-	m.prober = &prober{
-		recorder: &record.FakeRecorder{},
-		exec:     crashingExecProber{},
-	}
-
-	// doProbe should recover from the crash, and keep going.
-	expectContinue(t, w, w.doProbe(), "Crashing probe.")
-	expectResult(t, w, results.Success, "Crashing probe unchanged.")
-}
-
 func expectResult(t *testing.T, w *worker, expectedResult results.Result, msg string) {
 	result, ok := resultsManager(w.probeManager, w.probeType).Get(w.containerID)
 	if !ok {
@@ -345,12 +320,6 @@ func resultsManager(m *manager, probeType probeType) results.Manager {
 	panic(fmt.Errorf("Unhandled case: %v", probeType))
 }
 
-type crashingExecProber struct{}
-
-func (p crashingExecProber) Probe(_ exec.Cmd) (probe.Result, string, error) {
-	panic("Intentional Probe crash.")
-}
-
 func TestOnHoldOnLivenessOrStartupCheckFailure(t *testing.T) {
 	m := newTestManager()
 

pkg/proxy/userspace/proxier_test.go

@@ -33,7 +33,6 @@ import (
 	discovery "k8s.io/api/discovery/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
-	"k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/kubernetes/pkg/proxy"
 	ipttest "k8s.io/kubernetes/pkg/util/iptables/testing"
@@ -186,9 +185,6 @@ var tcpServerPort int32
 var udpServerPort int32
 
 func TestMain(m *testing.M) {
-	// Don't handle panics
-	runtime.ReallyCrash = true
-
 	// TCP setup.
 	tcp := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)

pkg/proxy/winuserspace/proxier_test.go

@@ -33,7 +33,6 @@ import (
 	discovery "k8s.io/api/discovery/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
-	"k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/kubernetes/pkg/proxy"
 	netshtest "k8s.io/kubernetes/pkg/util/netsh/testing"
 	netutils "k8s.io/utils/net"
@@ -115,9 +114,6 @@ var tcpServerPort int32
 var udpServerPort int32
 
 func TestMain(m *testing.M) {
-	// Don't handle panics
-	runtime.ReallyCrash = true
-
 	// TCP setup.
 	tcp := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)

staging/src/k8s.io/apimachinery/pkg/util/runtime/runtime.go

@@ -27,9 +27,10 @@ import (
 )
 
 var (
-	// ReallyCrash controls the behavior of HandleCrash and now defaults
-	// true. It's still exposed so components can optionally set to false
-	// to restore prior behavior.
+	// ReallyCrash controls the behavior of HandleCrash and defaults to
+	// true. It's exposed so components can optionally set to false
+	// to restore prior behavior. This flag is mostly used for tests to validate
+	// crash conditions.
 	ReallyCrash = true
 )
 

staging/src/k8s.io/apiserver/pkg/server/filters/wrap.go

@@ -41,8 +41,7 @@ func WithPanicRecovery(handler http.Handler, resolver request.RequestInfoResolve
 			// the client sees an interrupted response but the server doesn't log
 			// an error, panic with the value ErrAbortHandler.
 			//
-			// Note that the ReallyCrash variable controls the behaviour of the HandleCrash function
-			// So it might actually crash, after calling the handlers
+			// Note that HandleCrash function is actually crashing, after calling the handlers
 			if info, err := resolver.NewRequestInfo(req); err != nil {
 				metrics.RecordRequestAbort(req, nil)
 			} else {

test/e2e/e2e.go

@@ -39,7 +39,6 @@ import (
 	appsv1 "k8s.io/api/apps/v1"
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	runtimeutils "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/component-base/logs"
 	"k8s.io/component-base/version"
@@ -98,7 +97,6 @@ var _ = ginkgo.SynchronizedAfterSuite(func() {
 // generated in this directory, and cluster logs will also be saved.
 // This function is called on each Ginkgo node in parallel mode.
 func RunE2ETests(t *testing.T) {
-	runtimeutils.ReallyCrash = true
 	logs.InitLogs()
 	defer logs.FlushLogs()