--- xnu/xnu-517.7.21/iokit/Kernel/IOInterruptController.cpp
+++ xnu/xnu-344.32/iokit/Kernel/IOInterruptController.cpp
@@ -96,10 +96,10 @@
       originalNub = vector->nub;
       originalSource = vector->source;
       
-      // Physically disable the interrupt, but mark it as being enables in the hardware.
-      // The interruptDisabledSoft now indicates the driver's request for enablement.
-      disableVectorHard(vectorNumber, vector);
-      vector->interruptDisabledHard = 0;
+      // Save the dis/enable state for the original consumer's interrupt.
+      // Then disable the source
+      wasDisabledSoft = vector->interruptDisabledSoft;
+      disableInterrupt(originalNub, originalSource);
       
       // Initialize the new shared interrupt controller.
       error = vector->sharedController->initInterruptController(this,
@@ -125,17 +125,7 @@
       // put the original consumor's interrupt back to normal and
       // get rid of whats left of the shared controller.
       if (error != kIOReturnSuccess) {
-	// Save the driver's interrupt enablement state.
-	wasDisabledSoft = vector->interruptDisabledSoft;
-	
-	// Make the interrupt really hard disabled.
-	vector->interruptDisabledSoft = 1;
-	vector->interruptDisabledHard = 1;
-	
-	// Enable the original consumer's interrupt if needed.
-	if (!wasDisabledSoft) originalNub->enableInterrupt(originalSource);
         enableInterrupt(originalNub, originalSource);
-	
         vector->sharedController->release();
         vector->sharedController = 0;
         IOUnlock(vector->interruptLock);
@@ -148,13 +138,6 @@
       vector->source  = 0;
       vector->target  = vector->sharedController;
       vector->refCon  = 0;
-      
-      // Save the driver's interrupt enablement state.
-      wasDisabledSoft = vector->interruptDisabledSoft;
-      
-      // Make the interrupt really hard disabled.
-      vector->interruptDisabledSoft = 1;
-      vector->interruptDisabledHard = 1;
       
       // Enable the original consumer's interrupt if needed.
       if (!wasDisabledSoft) originalNub->enableInterrupt(originalSource);
@@ -416,7 +399,7 @@
   }
   
   // Allocate the memory for the vectors
-  numVectors = 32; // For now a constant number.
+  numVectors = 8; // For now a constant number.
   vectors = (IOInterruptVector *)IOMalloc(numVectors * sizeof(IOInterruptVector));
   if (vectors == NULL) {
     IOFree(_interruptSources, sizeof(IOInterruptSource));