t.Fatalf("failed to run the test program %q: %v\n%v", prog, err, cmd.Stderr)
			}

			prof, err := profile.Parse(bytes.NewReader(out))
			if err != nil {
				t.Fatalf("failed to parse the generated profile data: %v", err)
			}
			t.Logf("Profile: %s", prof)

			hit := make(map[*profile.Mapping]bool)
			miss := make(map[*profile.Mapping]bool)
			for _, loc := range prof.Location {
				if symbolized(loc) {

		logger.Info("Set sysctl", "entry", entry, "value", value)
		if err := sys.SetSysctl(entry, value); err != nil {
			return err
		}
	}
	return nil
}

// isSysFSWritable checks /proc/mounts to see whether sysfs is 'rw' or not.
func (rct realConntracker) isSysFSWritable(ctx context.Context) (bool, error) {
	logger := klog.FromContext(ctx)
	const permWritable = "rw"
	const sysfsDevice = "sysfs"

}

func doBindSubPath(mounter mount.Interface, subpath Subpath) (hostPath string, err error) {
	// Linux, kubelet runs on the host:
	// - safely open the subpath
	// - bind-mount /proc/<pid of kubelet>/fd/<fd> to subpath target
	// User can't change /proc/<pid of kubelet>/fd/<fd> to point to a bad place.

	// Evaluate all symlinks here once for all subsequent functions.
	newVolumePath, err := filepath.EvalSymlinks(subpath.VolumePath)

func isProcessRunningInHost(pid int) (bool, error) {
	// Get init pid namespace.
	initPidNs, err := os.Readlink("/proc/1/ns/pid")
	if err != nil {
		return false, fmt.Errorf("failed to find pid namespace of init process")
	}
	klog.V(10).InfoS("Found init PID namespace", "namespace", initPidNs)
	processPidNs, err := os.Readlink(fmt.Sprintf("/proc/%d/ns/pid", pid))
	if err != nil {

func (h *spliceFileHook) uninstall() {
	*PollSpliceFile = h.original
}

// On some kernels copy_file_range fails on files in /proc.
func TestProcCopy(t *testing.T) {
	t.Parallel()

	const cmdlineFile = "/proc/self/cmdline"
	cmdline, err := ReadFile(cmdlineFile)
	if err != nil {
		t.Skipf("can't read /proc file: %v", err)
	}
	in, err := Open(cmdlineFile)
	if err != nil {
		t.Fatal(err)
	}
	defer in.Close()

			// memory.swap.max does not exist in the cgroup root, so we check /sys/fs/cgroup/<SELF>/memory.swap.max
			_, unified, err := cgroups.ParseCgroupFileUnified("/proc/self/cgroup")
			if err != nil {
				klog.V(5).ErrorS(fmt.Errorf("failed to parse /proc/self/cgroup: %w", err), warn)
				return
			}
			p = filepath.Join("/sys/fs/cgroup", unified, "memory.swap.max")
		}
		if _, err := os.Stat(p); err != nil {

	expected := filter + expect
	pid := syscall.Getpid()
	fs, err := os.ReadDir(fmt.Sprintf("/proc/%d/task", pid))
	if err != nil {
		return fmt.Errorf("unable to find %d tasks: %v", pid, err)
	}
	expectedProc := fmt.Sprintf("Pid:\t%d", pid)
	foundAThread := false
	for _, f := range fs {
		tf := fmt.Sprintf("/proc/%s/status", f.Name())
		d, err := os.ReadFile(tf)
		if err != nil {

	pidle        puintptr // idle p's
	npidle       atomic.Int32
	nmspinning   atomic.Int32  // See "Worker thread parking/unparking" comment in proc.go.
	needspinning atomic.Uint32 // See "Delicate dance" comment in proc.go. Boolean. Must hold sched.lock to set to 1.

	// Global runnable queue.
	runq     gQueue
	runqsize int32

	// disable controls selective disabling of the scheduler.
	//

func (poc PortOpenCheck) Name() string {
	if poc.label != "" {
		return poc.label
	}
	return fmt.Sprintf("Port-%d", poc.port)
}

// Check validates if the particular port is available.
func (poc PortOpenCheck) Check() (warnings, errorList []error) {
	klog.V(1).Infof("validating availability of port %d", poc.port)

	ldr := ctxt.loader
	if ldr.Lookup("runtime.runtime_inittasks", 0) != 0 {
		t := ctxt.inittaskSym([]string{"runtime..inittask"}, "go:runtime.inittasks")

		// This slice header is already defined in runtime/proc.go, so we update it here with new contents.
		sh := ldr.Lookup("runtime.runtime_inittasks", 0)
		sb := ldr.MakeSymbolUpdater(sh)
		sb.SetSize(0)
		sb.SetType(sym.SNOPTRDATA) // Could be SRODATA, but see issue 58857.