diff -urN kvm-87/usb-linux.c kvm-87-debug/usb-linux.c
--- kvm-87/usb-linux.c	2009-06-23 09:32:38.000000000 -0400
+++ kvm-87-debug/usb-linux.c	2009-07-16 03:06:22.000000000 -0400
@@ -209,16 +209,21 @@
 
 static AsyncURB *async_alloc(void)
 {
-    return (AsyncURB *) qemu_mallocz(sizeof(AsyncURB));
+    AsyncURB *aurb = (AsyncURB *) qemu_mallocz(sizeof(AsyncURB));
+    dprintf("husb: allocated %p\n", aurb);
+    return aurb;
 }
 
 static void async_free(AsyncURB *aurb)
 {
+    dprintf("husb: freeing %p\n", aurb);
     qemu_free(aurb);
 }
 
 static void async_complete_ctrl(USBHostDevice *s, USBPacket *p)
 {
+    dprintf("husb: complete ctrl, host state %d len %d\n", 
+	    s->ctrl.state, s->ctrl.len);
     switch(s->ctrl.state) {
     case CTRL_STATE_SETUP:
         if (p->len < s->ctrl.len)
@@ -266,6 +271,7 @@
                 aurb, aurb->urb.status, aurb->urb.actual_length);
 
 	if (p) {
+	    dprintf("husb: p=%p\n", p);
             switch (aurb->urb.status) {
             case 0:
                 p->len = aurb->urb.actual_length;
@@ -280,11 +286,12 @@
                 p->len = USB_RET_NAK;
                 break;
             }
-
+	    dprintf("husb: completing, p->len=%d\n", p->len);
             usb_packet_complete(p);
 	}
 
         async_free(aurb);
+
     }
 }