RTDECL(int)  RTSemEventDestroy(RTSEMEVENT hEventSem)
{
    IPRT_LINUX_SAVE_EFL_AC();

    /*
     * Validate input.
     */
    PRTSEMEVENTINTERNAL pThis = hEventSem;
    if (pThis == NIL_RTSEMEVENT)
        return VINF_SUCCESS;
    AssertMsgReturn(pThis->u32Magic == RTSEMEVENT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis), VERR_INVALID_HANDLE);
    Assert(pThis->cRefs > 0);

    /*
     * Invalidate it and signal the object just in case.
     */
    ASMAtomicWriteU32(&pThis->u32Magic, ~RTSEMEVENT_MAGIC);
    ASMAtomicWriteU32(&pThis->fState, 0);
    Assert(!waitqueue_active(&pThis->Head));
    wake_up_all(&pThis->Head);
    rtR0SemEventLnxRelease(pThis);

    IPRT_LINUX_RESTORE_EFL_AC();
    return VINF_SUCCESS;
}

/**
 * Records a invlpg instruction for replaying upon REM entry.
 *
 * @param   pVM         Pointer to the VM.
 * @param   GCPtrPage   The
 */
VMMDECL(void) REMNotifyInvalidatePage(PVM pVM, RTGCPTR GCPtrPage)
{
    /*
     * Try take the REM lock and push the address onto the array.
     */
    if (   pVM->rem.s.cInvalidatedPages < RT_ELEMENTS(pVM->rem.s.aGCPtrInvalidatedPages)
        && EMRemTryLock(pVM) == VINF_SUCCESS)
    {
        uint32_t iPage = pVM->rem.s.cInvalidatedPages;
        if (iPage < RT_ELEMENTS(pVM->rem.s.aGCPtrInvalidatedPages))
        {
            ASMAtomicWriteU32(&pVM->rem.s.cInvalidatedPages, iPage + 1);
            pVM->rem.s.aGCPtrInvalidatedPages[iPage] = GCPtrPage;

            EMRemUnlock(pVM);
            return;
        }

        CPUMSetChangedFlags(VMMGetCpu(pVM), CPUM_CHANGED_GLOBAL_TLB_FLUSH); /** @todo this array should be per-cpu technically speaking. */
        ASMAtomicWriteU32(&pVM->rem.s.cInvalidatedPages, 0); /** @todo leave this alone? Optimize this code? */

        EMRemUnlock(pVM);
    }
    else
    {
        /* Fallback: Simply tell the recompiler to flush its TLB. */
        CPUMSetChangedFlags(VMMGetCpu(pVM), CPUM_CHANGED_GLOBAL_TLB_FLUSH);
        ASMAtomicWriteU32(&pVM->rem.s.cInvalidatedPages, 0); /** @todo leave this alone?! Optimize this code? */
    }

    return;
}

int vboxNetAdpCreate(PVBOXNETADP *ppNew, const char *pcszName)
{
    int rc;
    unsigned i;
    for (i = 0; i < RT_ELEMENTS(g_aAdapters); i++)
    {
        PVBOXNETADP pThis = &g_aAdapters[i];

        if (ASMAtomicCmpXchgU32((uint32_t volatile *)&pThis->enmState, kVBoxNetAdpState_Transitional, kVBoxNetAdpState_Invalid))
        {
            RTMAC Mac;
            /* Found an empty slot -- use it. */
            Log(("vboxNetAdpCreate: found empty slot: %d\n", i));
            if (pcszName)
            {
                Log(("vboxNetAdpCreate: using name: %s\n", pcszName));
                pThis->iUnit = vboxNetAdpGetUnitByName(pcszName);
                strncpy(pThis->szName, pcszName, sizeof(pThis->szName));
                pThis->szName[sizeof(pThis->szName) - 1] = '\0';
            }
            else
            {
                pThis->iUnit = vboxNetAdpGetNextAvailableUnit();
                pThis->szName[0] = '\0';
            }
            if (pThis->iUnit < 0)
                rc = VERR_INVALID_PARAMETER;
            else
            {
                vboxNetAdpComposeMACAddress(pThis, &Mac);
                rc = vboxNetAdpOsCreate(pThis, &Mac);
                Log(("vboxNetAdpCreate: pThis=%p pThis->iUnit=%d, pThis->szName=%s\n",
                     pThis, pThis->iUnit, pThis->szName));
            }
            if (RT_SUCCESS(rc))
            {
                *ppNew = pThis;
                ASMAtomicWriteU32((uint32_t volatile *)&pThis->enmState, kVBoxNetAdpState_Active);
                Log2(("VBoxNetAdpCreate: Created %s\n", g_aAdapters[i].szName));
            }
            else
            {
                ASMAtomicWriteU32((uint32_t volatile *)&pThis->enmState, kVBoxNetAdpState_Invalid);
                Log(("vboxNetAdpCreate: vboxNetAdpOsCreate failed with '%Rrc'.\n", rc));
            }
            for (i = 0; i < RT_ELEMENTS(g_aAdapters); i++)
                Log2(("VBoxNetAdpCreate: Scanning entry: state=%d unit=%d name=%s\n",
                      g_aAdapters[i].enmState, g_aAdapters[i].iUnit, g_aAdapters[i].szName));
            return rc;
        }
    }
    Log(("vboxNetAdpCreate: no empty slots!\n"));

    /* All slots in adapter array are busy. */
    return VERR_OUT_OF_RESOURCES;
}

RTDECL(void) RTSpinlockRelease(RTSPINLOCK Spinlock)
{
    PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
    AssertMsg(pThis && pThis->u32Magic == RTSPINLOCK_MAGIC, ("magic=%#x\n", pThis->u32Magic));

    KIRQL SavedIrql = pThis->SavedIrql;
    if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE)
    {
        RTCCUINTREG fIntSaved = pThis->fIntSaved;
        pThis->fIntSaved = 0;

#ifndef RTSPINLOCK_NT_HACK_NOIRQ
        KeReleaseSpinLock(&pThis->Spinlock, SavedIrql);
        ASMSetFlags(fIntSaved);
#else
        Assert(pThis->u32Hack == RTSPINLOCK_NT_HACK_NOIRQ_TAKEN);

        ASMAtomicWriteU32(&pThis->u32Hack, RTSPINLOCK_NT_HACK_NOIRQ_FREE);
        ASMSetFlags(fIntSaved);
        if (SavedIrql < DISPATCH_LEVEL)
            KeLowerIrql(SavedIrql);
#endif
    }
    else
        KeReleaseSpinLock(&pThis->Spinlock, SavedIrql);
}

RTDECL(int) RTSemEventMultiSignal(RTSEMEVENTMULTI hEventMultiSem)
{
    PRTSEMEVENTMULTIINTERNAL pThis = (PRTSEMEVENTMULTIINTERNAL)hEventMultiSem;
    RT_ASSERT_PREEMPT_CPUID_VAR();

    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
    AssertMsgReturn(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC,
                    ("pThis=%p u32Magic=%#x\n", pThis, pThis->u32Magic),
                    VERR_INVALID_HANDLE);
    RT_ASSERT_INTS_ON();
    rtR0SemEventMultiSolRetain(pThis);
    rtR0SemSolWaitEnterMutexWithUnpinningHack(&pThis->Mtx);
    Assert(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC);

    /*
     * Do the job.
     */
    uint32_t fNew = ASMAtomicUoReadU32(&pThis->fStateAndGen);
    fNew += 1 << RTSEMEVENTMULTISOL_GEN_SHIFT;
    fNew |= RTSEMEVENTMULTISOL_STATE_MASK;
    ASMAtomicWriteU32(&pThis->fStateAndGen, fNew);

    cv_broadcast(&pThis->Cnd);

    mutex_exit(&pThis->Mtx);

    rtR0SemEventMultiSolRelease(pThis);
    RT_ASSERT_PREEMPT_CPUID();
    return VINF_SUCCESS;
}

RTDECL(int) RTSemSpinMutexDestroy(RTSEMSPINMUTEX hSpinMtx)
{
    RTSEMSPINMUTEXINTERNAL *pThis;
    RTSEMEVENT              hEventSem;
    int                     rc;

    if (hSpinMtx == NIL_RTSEMSPINMUTEX)
        return VINF_SUCCESS;
    pThis = hSpinMtx;
    RTSEMSPINMUTEX_VALIDATE_RETURN(pThis);

    /* No destruction races allowed! */
    AssertMsg(   pThis->cLockers  == 0
              && pThis->hOwner    == NIL_RTNATIVETHREAD,
              ("pThis=%p cLockers=%d hOwner=%p\n", pThis, pThis->cLockers, pThis->hOwner));

    /*
     * Invalidate the structure, free the mutex and free the structure.
     */
    ASMAtomicWriteU32(&pThis->u32Magic, RTSEMSPINMUTEX_MAGIC_DEAD);
    hEventSem        = pThis->hEventSem;
    pThis->hEventSem = NIL_RTSEMEVENT;
    rc = RTSemEventDestroy(hEventSem); AssertRC(rc);

    RTMemFree(pThis);
    return rc;
}

RTDECL(int)  RTSemEventMultiSignal(RTSEMEVENTMULTI hEventMultiSem)
{
    PRTSEMEVENTMULTIINTERNAL pThis = (PRTSEMEVENTMULTIINTERNAL)hEventMultiSem;
    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
    AssertMsgReturn(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC, ("pThis=%p u32Magic=%#x\n", pThis, pThis->u32Magic), VERR_INVALID_HANDLE);
    RT_ASSERT_PREEMPT_CPUID_VAR();
    RT_ASSERT_INTS_ON();

    rtR0SemEventMultiDarwinRetain(pThis);
    lck_spin_lock(pThis->pSpinlock);

    /*
     * Set the signal and increment the generation counter.
     */
    uint32_t fNew = ASMAtomicUoReadU32(&pThis->fStateAndGen);
    fNew += 1 << RTSEMEVENTMULTIDARWIN_GEN_SHIFT;
    fNew |= RTSEMEVENTMULTIDARWIN_STATE_MASK;
    ASMAtomicWriteU32(&pThis->fStateAndGen, fNew);

    /*
     * Wake up all sleeping threads.
     */
    if (pThis->fHaveBlockedThreads)
    {
        ASMAtomicWriteBool(&pThis->fHaveBlockedThreads, false);
        thread_wakeup_prim((event_t)pThis, FALSE /* all threads */, THREAD_AWAKENED);
    }

    lck_spin_unlock(pThis->pSpinlock);
    rtR0SemEventMultiDarwinRelease(pThis);

    RT_ASSERT_PREEMPT_CPUID();
    return VINF_SUCCESS;
}

RTDECL(int) RTTimerDestroy(PRTTIMER pTimer)
{
    if (pTimer == NULL)
        return VINF_SUCCESS;
    RTTIMER_ASSERT_VALID_RET(pTimer);
    RT_ASSERT_INTS_ON();

    /*
     * It is not possible to destroy a timer from it's callback function.
     * Cyclic makes that impossible (or at least extremely risky).
     */
    AssertReturn(!rtTimerSolIsCallingFromTimerProc(pTimer), VERR_INVALID_CONTEXT);

    /*
     * Invalidate the handle, make sure it's stopped and free the associated resources.
     */
    ASMAtomicWriteU32(&pTimer->u32Magic, ~RTTIMER_MAGIC);

    if (   !pTimer->fSuspended
        || pTimer->hCyclicId != CYCLIC_NONE) /* 2nd check shouldn't happen */
        rtTimerSolStopIt(pTimer);

    rtTimerSolRelease(pTimer);
    return VINF_SUCCESS;
}

/**
 * Destroys the timer when the reference counter has reached zero.
 *
 * @returns 0 (new references counter value).
 * @param   pTimer              The timer.
 */
static uint32_t rtTimeSolReleaseCleanup(PRTTIMER pTimer)
{
    Assert(pTimer->hCyclicId == CYCLIC_NONE);
    ASMAtomicWriteU32(&pTimer->u32Magic, ~RTTIMER_MAGIC);
    RTMemFree(pTimer);
    return 0;
}

RTDECL(int) RTTimerDestroy(PRTTIMER pTimer)
{
    /* It's ok to pass NULL pointer. */
    if (pTimer == /*NIL_RTTIMER*/ NULL)
        return VINF_SUCCESS;
    AssertPtrReturn(pTimer, VERR_INVALID_HANDLE);
    AssertReturn(pTimer->u32Magic == RTTIMER_MAGIC, VERR_INVALID_HANDLE);

    /*
     * We do not support destroying a timer from the callback because it is
     * not 101% safe since we cannot flush DPCs.  Solaris has the same restriction.
     */
    AssertReturn(KeGetCurrentIrql() == PASSIVE_LEVEL, VERR_INVALID_CONTEXT);

    /*
     * Invalidate the timer, stop it if it's running and finally
     * free up the memory.
     */
    ASMAtomicWriteU32(&pTimer->u32Magic, ~RTTIMER_MAGIC);
    if (!ASMAtomicUoReadBool(&pTimer->fSuspended))
        rtTimerNtStopWorker(pTimer);

    /*
     * Flush DPCs to be on the safe side.
     */
    if (g_pfnrtNtKeFlushQueuedDpcs)
        g_pfnrtNtKeFlushQueuedDpcs();

    RTMemFree(pTimer);

    return VINF_SUCCESS;
}

RTDECL(int)  RTSemMutexDestroy(RTSEMMUTEX hMutexSem)
{
    /*
     * Validate input.
     */
    if (hMutexSem == NIL_RTSEMMUTEX)
        return VINF_SUCCESS;
    struct RTSEMMUTEXINTERNAL *pThis = hMutexSem;
    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
    AssertMsgReturn(pThis->u32Magic == RTSEMMUTEX_MAGIC,
                    ("hMutexSem=%p u32Magic=%#x\n", pThis, pThis->u32Magic),
                    VERR_INVALID_HANDLE);

    /*
     * Invalidate the semaphore and wake up anyone waiting on it.
     */
    ASMAtomicWriteU32(&pThis->u32Magic, RTSEMMUTEX_MAGIC_DEAD);
    if (ASMAtomicXchgS32(&pThis->iState, 0) > 0)
    {
        sys_futex(&pThis->iState, FUTEX_WAKE, INT_MAX, NULL, NULL, 0);
        usleep(1000);
    }
    pThis->Owner        = (pthread_t)~0;
    pThis->cNestings    = 0;
#ifdef RTSEMMUTEX_STRICT
    RTLockValidatorRecExclDelete(&pThis->ValidatorRec);
#endif

    /*
     * Free the semaphore memory and be gone.
     */
    RTMemFree(pThis);
    return VINF_SUCCESS;
}

RTDECL(int)  RTSemEventSignal(RTSEMEVENT hEventSem)
{
    /*
     * Validate input.
     */
    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
    AssertReturn(pThis->iMagic == RTSEMEVENT_MAGIC, VERR_INVALID_HANDLE);

#ifdef RTSEMEVENT_STRICT
    if (pThis->fEverHadSignallers)
    {
        int rc9 = RTLockValidatorRecSharedCheckSignaller(&pThis->Signallers, NIL_RTTHREAD);
        if (RT_FAILURE(rc9))
            return rc9;
    }
#endif

    ASMAtomicWriteU32(&pThis->fSignalled, 1);
    if (ASMAtomicReadS32(&pThis->cWaiters) < 1)
        return VINF_SUCCESS;

    /* somebody is waiting, try wake up one of them. */
    long cWoken = sys_futex(&pThis->fSignalled, FUTEX_WAKE, 1, NULL, NULL, 0);
    if (RT_LIKELY(cWoken >= 0))
        return VINF_SUCCESS;

    if (RT_UNLIKELY(pThis->iMagic != RTSEMEVENT_MAGIC))
        return VERR_SEM_DESTROYED;

    return VERR_INVALID_PARAMETER;
}

RTDECL(int)  RTSemEventMultiDestroy(RTSEMEVENTMULTI hEventMultiSem)
{
    /*
     * Validate input.
     */
    struct RTSEMEVENTMULTIINTERNAL *pThis = hEventMultiSem;
    if (pThis == NIL_RTSEMEVENTMULTI)
        return VINF_SUCCESS;
    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
    AssertReturn(pThis->u32Magic == RTSEMEVENTMULTI_MAGIC, VERR_INVALID_HANDLE);

    /*
     * Invalidate the semaphore and wake up anyone waiting on it.
     */
    ASMAtomicWriteU32(&pThis->u32Magic, RTSEMEVENTMULTI_MAGIC + 1);
    if (ASMAtomicXchgS32(&pThis->iState, -1) == 1)
    {
        sys_futex(&pThis->iState, FUTEX_WAKE, INT_MAX, NULL, NULL, 0);
        usleep(1000);
    }

    /*
     * Free the semaphore memory and be gone.
     */
#ifdef RTSEMEVENTMULTI_STRICT
    RTLockValidatorRecSharedDelete(&pThis->Signallers);
#endif
    RTMemFree(pThis);
    return VINF_SUCCESS;
}

static PVBOXDISPMPLOGGER vboxDispMpLoggerGet()
{
    if (ASMAtomicCmpXchgU32((volatile uint32_t *)&g_VBoxDispMpLogger.enmState, VBOXDISPMPLOGGER_STATE_INITIALIZING, VBOXDISPMPLOGGER_STATE_UNINITIALIZED))
    {
        HRESULT hr = vboxDispKmtCallbacksInit(&g_VBoxDispMpLogger.KmtCallbacks);
        if (hr == S_OK)
        {
            /* we are on Vista+
             * check if we can Open Adapter, i.e. WDDM driver is installed */
            VBOXDISPKMT_ADAPTER Adapter;
            hr = vboxDispKmtOpenAdapter(&g_VBoxDispMpLogger.KmtCallbacks, &Adapter);
            if (hr == S_OK)
            {
                ASMAtomicWriteU32((volatile uint32_t *)&g_VBoxDispMpLogger.enmState, VBOXDISPMPLOGGER_STATE_INITIALIZED);
                vboxDispKmtCloseAdapter(&Adapter);
                return &g_VBoxDispMpLogger;
            }
            vboxDispKmtCallbacksTerm(&g_VBoxDispMpLogger.KmtCallbacks);
        }
    }
    else if (ASMAtomicReadU32((volatile uint32_t *)&g_VBoxDispMpLogger.enmState) == VBOXDISPMPLOGGER_STATE_INITIALIZED)
    {
        return &g_VBoxDispMpLogger;
    }
    return NULL;
}

/**
 * Destroys an module after the reference count has reached zero.
 *
 * @param   pDbgMod     The module instance.
 */
static void rtDbgModDestroy(PRTDBGMODINT pDbgMod)
{
    /*
     * Close the debug info interpreter first, then the image interpret.
     */
    RTCritSectEnter(&pDbgMod->CritSect); /* paranoia  */

    if (pDbgMod->pDbgVt)
    {
        pDbgMod->pDbgVt->pfnClose(pDbgMod);
        pDbgMod->pDbgVt = NULL;
        pDbgMod->pvDbgPriv = NULL;
    }

    if (pDbgMod->pImgVt)
    {
        pDbgMod->pImgVt->pfnClose(pDbgMod);
        pDbgMod->pImgVt = NULL;
        pDbgMod->pvImgPriv = NULL;
    }

    /*
     * Free the resources.
     */
    ASMAtomicWriteU32(&pDbgMod->u32Magic, ~RTDBGMOD_MAGIC);
    RTStrCacheRelease(g_hDbgModStrCache, pDbgMod->pszName);
    RTStrCacheRelease(g_hDbgModStrCache, pDbgMod->pszImgFile);
    RTStrCacheRelease(g_hDbgModStrCache, pDbgMod->pszDbgFile);
    RTCritSectLeave(&pDbgMod->CritSect); /* paranoia  */
    RTCritSectDelete(&pDbgMod->CritSect);
    RTMemFree(pDbgMod);
}

RTDECL(int)  RTSemEventDestroy(RTSEMEVENT hEventSem)
{
    /*
     * Validate handle.
     */
    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
    if (pThis == NIL_RTSEMEVENT)
        return VINF_SUCCESS;
    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
    uint32_t    u32 = pThis->u32State;
    AssertReturn(u32 == EVENT_STATE_NOT_SIGNALED || u32 == EVENT_STATE_SIGNALED, VERR_INVALID_HANDLE);

    /*
     * Abort all waiters forcing them to return failure.
     */
    int rc;
    for (int i = 30; i > 0; i--)
    {
        ASMAtomicWriteU32(&pThis->u32State, EVENT_STATE_UNINITIALIZED);
        rc = pthread_cond_destroy(&pThis->Cond);
        if (rc != EBUSY)
            break;
        pthread_cond_broadcast(&pThis->Cond);
        usleep(1000);
    }
    if (rc)
    {
        AssertMsgFailed(("Failed to destroy event sem %p, rc=%d.\n", pThis, rc));
        return RTErrConvertFromErrno(rc);
    }

    /*
     * Destroy the semaphore
     * If it's busy we'll wait a bit to give the threads a chance to be scheduled.
     */
    for (int i = 30; i > 0; i--)
    {
        rc = pthread_mutex_destroy(&pThis->Mutex);
        if (rc != EBUSY)
            break;
        usleep(1000);
    }
    if (rc)
    {
        AssertMsgFailed(("Failed to destroy event sem %p, rc=%d. (mutex)\n", pThis, rc));
        return RTErrConvertFromErrno(rc);
    }

    /*
     * Free the semaphore memory and be gone.
     */
#ifdef RTSEMEVENT_STRICT
    RTLockValidatorRecSharedDelete(&pThis->Signallers);
#endif
    if (!(pThis->fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK))
        RTMemFree(pThis);
    else
        rtMemBaseFree(pThis);
    return VINF_SUCCESS;
}

/**
 * Mac OS X: Really ugly hack to bypass a set-uid check in AppKit.
 *
 * This will modify the issetugid() function to always return zero.  This must
 * be done _before_ AppKit is initialized, otherwise it will refuse to play ball
 * with us as it distrusts set-uid processes since Snow Leopard.  We, however,
 * have carefully dropped all root privileges at this point and there should be
 * no reason for any security concern here.
 */
static void HideSetUidRootFromAppKit()
{
    /* Find issetguid() and make it always return 0 by modifying the code: */
    void *pvAddr = dlsym(RTLD_DEFAULT, "issetugid");
    int rc = mprotect((void *)((uintptr_t)pvAddr & ~(uintptr_t)0xfff), 0x2000, PROT_WRITE | PROT_READ | PROT_EXEC);
    if (!rc)
        ASMAtomicWriteU32((volatile uint32_t *)pvAddr, 0xccc3c031); /* xor eax, eax; ret; int3 */
}

static int pdmacFileAioMgrWaitForBlockingEvent(PPDMACEPFILEMGR pAioMgr, PDMACEPFILEAIOMGRBLOCKINGEVENT enmEvent)
{
    ASMAtomicWriteU32((volatile uint32_t *)&pAioMgr->enmBlockingEvent, enmEvent);
    Assert(!pAioMgr->fBlockingEventPending);
    ASMAtomicXchgBool(&pAioMgr->fBlockingEventPending, true);

    /* Wakeup the async I/O manager */
    pdmacFileAioMgrWakeup(pAioMgr);

    /* Wait for completion. */
    int rc = RTSemEventWait(pAioMgr->EventSemBlock, RT_INDEFINITE_WAIT);
    AssertRC(rc);

    ASMAtomicXchgBool(&pAioMgr->fBlockingEventPending, false);
    ASMAtomicWriteU32((volatile uint32_t *)&pAioMgr->enmBlockingEvent, PDMACEPFILEAIOMGRBLOCKINGEVENT_INVALID);

    return rc;
}

RTDECL(int)  RTSemEventDestroy(RTSEMEVENT hEventSem)
{
    /*
     * Validate input.
     */
    PRTSEMEVENTINTERNAL pThis = hEventSem;
    if (pThis == NIL_RTSEMEVENT)
        return VINF_SUCCESS;
    AssertMsgReturn(pThis->u32Magic == RTSEMEVENT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis), VERR_INVALID_HANDLE);
    Assert(pThis->cRefs > 0);

    /*
     * Invalidate it and signal the object just in case.
     */
    ASMAtomicWriteU32(&pThis->u32Magic, ~RTSEMEVENT_MAGIC);
    ASMAtomicWriteU32(&pThis->fState, 0);
    rtR0SemBsdBroadcast(pThis);
    rtR0SemEventBsdRelease(pThis);
    return VINF_SUCCESS;
}

RTDECL(int)  RTSemFastMutexDestroy(RTSEMFASTMUTEX hFastMtx)
{
    PRTSEMFASTMUTEXINTERNAL pThis = hFastMtx;
    if (pThis == NIL_RTSEMFASTMUTEX)
        return VINF_SUCCESS;
    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
    AssertMsgReturn(pThis->u32Magic == RTSEMFASTMUTEX_MAGIC, ("%p: u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_HANDLE);

    ASMAtomicWriteU32(&pThis->u32Magic, RTSEMFASTMUTEX_MAGIC_DEAD);
    sx_destroy(&pThis->SxLock);
    RTMemFree(pThis);

    return VINF_SUCCESS;
}