--- xnu/xnu-792.25.20/iokit/Kernel/IOWorkLoop.cpp
+++ xnu/xnu-344.2/iokit/Kernel/IOWorkLoop.cpp
@@ -38,8 +38,8 @@
 
 // Block of unused functions intended for future use
 OSMetaClassDefineReservedUsed(IOWorkLoop, 0);
-OSMetaClassDefineReservedUsed(IOWorkLoop, 1);
-
+
+OSMetaClassDefineReservedUnused(IOWorkLoop, 1);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 2);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 3);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 4);
@@ -57,6 +57,18 @@
 
 #define fFlags loopRestart
 
+extern "C" extern void stack_privilege( thread_t thread);
+
+void IOWorkLoop::launchThreadMain(void *self)
+{
+    register thread_t mythread = current_thread();
+
+    // Make sure that this thread always has a kernel stack
+    stack_privilege(mythread);
+    thread_set_cont_arg((int) self);
+    threadMainContinuation();
+}
+
 bool IOWorkLoop::init()
 {
     // The super init and gateLock allocation MUST be done first
@@ -70,8 +82,7 @@
         return false;
 
     controlG = IOCommandGate::
-	commandGate(this, OSMemberFunctionCast(IOCommandGate::Action,
-					this, &IOWorkLoop::_maintRequest));
+	commandGate(this, (IOCommandGate::Action) &IOWorkLoop::_maintRequest);
     if ( !controlG )
         return false;
 
@@ -85,9 +96,7 @@
     if (addEventSource(controlG) != kIOReturnSuccess)
         return false;
 
-    IOThreadFunc cptr =
-	OSMemberFunctionCast(IOThreadFunc, this, &IOWorkLoop::threadMain);
-    workThread = IOCreateThread(cptr, this);
+    workThread = IOCreateThread(launchThreadMain, (void *) this);
     if (!workThread)
         return false;
 
@@ -100,7 +109,7 @@
     IOWorkLoop *me = new IOWorkLoop;
 
     if (me && !me->init()) {
-        me->release();
+        me->free();
         return 0;
     }
 
@@ -243,55 +252,56 @@
 
 #endif /* KDEBUG */
 
-/* virtual */ bool IOWorkLoop::runEventSources()
-{
-    bool res = false;
-    closeGate();
-    if (ISSETP(&fFlags, kLoopTerminate))
-	goto abort;
+void IOWorkLoop::threadMainContinuation()
+{
+  IOWorkLoop* self;
+  self = (IOWorkLoop *) thread_get_cont_arg();
+
+  self->threadMain();
+}
+
+void IOWorkLoop::threadMain()
+{
+    CLRP(&fFlags, kLoopRestart);
+
+    for (;;) {
+        bool more;
+	IOInterruptState is;
 
     IOTimeWorkS();
-    bool more;
-    do {
-	CLRP(&fFlags, kLoopRestart);
-	workToDo = more = false;
-	for (IOEventSource *evnt = eventChain; evnt; evnt = evnt->getNext()) {
-
-	    IOTimeClientS();
-	    more |= evnt->checkForWork();
-	    IOTimeClientE();
-
-	    if (ISSETP(&fFlags, kLoopTerminate))
-		goto abort;
-	    else if (fFlags & kLoopRestart) {
-		more = true;
-		break;
-	    }
-	}
-    } while (more);
-
-    res = true;
+
+        closeGate();
+        if (ISSETP(&fFlags, kLoopTerminate))
+	    goto exitThread;
+
+        do {
+            workToDo = more = false;
+            for (IOEventSource *event = eventChain; event; event = event->getNext()) {
+
+            IOTimeClientS();
+                more |= event->checkForWork();
+            IOTimeClientE();
+
+		if (ISSETP(&fFlags, kLoopTerminate))
+		    goto exitThread;
+                else if (fFlags & kLoopRestart) {
+		    CLRP(&fFlags, kLoopRestart);
+                    continue;
+                }
+            }
+        } while (more);
+
     IOTimeWorkE();
 
-abort:
-    openGate();
-    return res;
-}
-
-/* virtual */ void IOWorkLoop::threadMain()
-{
-    do {
-	if ( !runEventSources() )
-	    goto exitThread;
-
-	IOInterruptState is = IOSimpleLockLockDisableInterrupt(workToDoLock);
+        openGate();
+
+	is = IOSimpleLockLockDisableInterrupt(workToDoLock);
         if ( !ISSETP(&fFlags, kLoopTerminate) && !workToDo) {
 	    assert_wait((void *) &workToDo, false);
 	    IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
 
-	    thread_continue_t cptr = OSMemberFunctionCast(
-		    thread_continue_t, this, &IOWorkLoop::threadMain);
-	    thread_block_parameter(cptr, this);
+	    thread_set_cont_arg((int) this);
+	    thread_block(&threadMainContinuation);
 	    /* NOTREACHED */
 	}
 
@@ -299,7 +309,11 @@
 	// to commit suicide.  But no matter 
 	// Clear the simple lock and retore the interrupt state
 	IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
-    } while(workToDo);
+	if (workToDo)
+	    continue;
+	else
+	    break;
+    }
 
 exitThread:
     workThread = 0;	// Say we don't have a loop and free ourselves
@@ -359,8 +373,8 @@
 }
 
 IOReturn IOWorkLoop::runAction(Action inAction, OSObject *target,
-                                  void *arg0, void *arg1,
-                                  void *arg2, void *arg3)
+                                  void *arg0 = 0, void *arg1 = 0,
+                                  void *arg2 = 0, void *arg3 = 0)
 {
     IOReturn res;