Index: VirtualBox-7.0.8/src/VBox/HostDrivers/Support/SUPDrvGip.cpp
===================================================================
--- VirtualBox-7.0.8.orig/src/VBox/HostDrivers/Support/SUPDrvGip.cpp
+++ VirtualBox-7.0.8/src/VBox/HostDrivers/Support/SUPDrvGip.cpp
@@ -4537,9 +4537,11 @@ static int supdrvTscDeltaThreadWait(PSUP
  */
 static void supdrvTscDeltaThreadStartMeasurement(PSUPDRVDEVEXT pDevExt, bool fForceAll)
 {
+    if (!pDevExt || ! pDevExt->hTscDeltaSpinlock)
+	return;
+    RTSpinlockAcquire(pDevExt->hTscDeltaSpinlock);
     if (pDevExt->hTscDeltaThread != NIL_RTTHREAD)
     {
-        RTSpinlockAcquire(pDevExt->hTscDeltaSpinlock);
         if (   pDevExt->enmTscDeltaThreadState == kTscDeltaThreadState_Listening
             || pDevExt->enmTscDeltaThreadState == kTscDeltaThreadState_Measuring)
         {
@@ -4550,9 +4552,9 @@ static void supdrvTscDeltaThreadStartMea
         else if (   pDevExt->enmTscDeltaThreadState == kTscDeltaThreadState_WaitAndMeasure
                  && fForceAll)
             pDevExt->fTscThreadRecomputeAllDeltas = true;
-        RTSpinlockRelease(pDevExt->hTscDeltaSpinlock);
         RTThreadUserSignal(pDevExt->hTscDeltaThread);
     }
+    RTSpinlockRelease(pDevExt->hTscDeltaSpinlock);
 }