stopVMM: ignore "process already finished"

Falling back to the first idea: instead of racing to see if the process
is finished, always signal, and ignore the instances where the signal
wasn't needed.

Signed-off-by: Peter Wagner <[email protected]>

Author: thepwagner

machine.go

@@ -23,6 +23,7 @@ import (
 	"os/signal"
 	"path/filepath"
 	"strconv"
+	"strings"
 	"sync"
 	"syscall"
 	"time"
@@ -576,9 +577,13 @@ func (m *Machine) StopVMM() error {
 }
 
 func (m *Machine) stopVMM() error {
-	if m.cmd != nil && m.cmd.Process != nil && m.cmd.ProcessState == nil {
+	if m.cmd != nil && m.cmd.Process != nil {
 		m.logger.Debug("stopVMM(): sending sigterm to firecracker")
-		return m.cmd.Process.Signal(syscall.SIGTERM)
+		err := m.cmd.Process.Signal(syscall.SIGTERM)
+		if err != nil && !strings.Contains(err.Error(), "os: process already finished") {
+			return err
+		}
+		return nil
 	}
 	m.logger.Debug("stopVMM(): no firecracker process running, not sending a signal")