diff --git a/vmkdrivers/src_9/drivers/usb/core/urb.c b/vmkdrivers/src_9/drivers/usb/core/urb.c
index 3a68c788aeb68c46741cd27ca035f06245c4f75f..4fb99a66e5275b5d20e2fda5ab3a0333050cf4c6 100644
--- a/vmkdrivers/src_9/drivers/usb/core/urb.c
+++ b/vmkdrivers/src_9/drivers/usb/core/urb.c
@@ -149,6 +149,16 @@ void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor)
 }
 EXPORT_SYMBOL_GPL(usb_anchor_urb);
 
+/* Callers must hold anchor->lock */
+static void __usb_unanchor_urb(struct urb *urb, struct usb_anchor *anchor)
+{
+        urb->anchor = NULL;
+        list_del(&urb->anchor_list);
+        usb_put_urb(urb);
+        if (list_empty(&anchor->urb_list))
+                wake_up(&anchor->wait);
+}
+
 /**
  * usb_unanchor_urb - unanchors an URB
  * @urb: pointer to the urb to anchor
@@ -168,17 +178,13 @@ void usb_unanchor_urb(struct urb *urb)
 		return;
 
 	spin_lock_irqsave(&anchor->lock, flags);
-	if (unlikely(anchor != urb->anchor)) {
-		/* we've lost the race to another thread */
-		spin_unlock_irqrestore(&anchor->lock, flags);
-		return;
-	}
-	urb->anchor = NULL;
-	list_del(&urb->anchor_list);
+        /* At this point, we could be competing with another thread which
+         * has the same intention. To protect the urb from being unanchored
+         * twice, only the winner of the race gets the job.
+         */
+        if (likely(anchor == urb->anchor))
+                __usb_unanchor_urb(urb, anchor);
 	spin_unlock_irqrestore(&anchor->lock, flags);
-	usb_put_urb(urb);
-	if (list_empty(&anchor->urb_list))
-		wake_up(&anchor->wait);
 }
 EXPORT_SYMBOL_GPL(usb_unanchor_urb);
 
@@ -828,20 +834,11 @@ EXPORT_SYMBOL_GPL(usb_unpoison_anchored_urbs);
 void usb_unlink_anchored_urbs(struct usb_anchor *anchor)
 {
 	struct urb *victim;
-	unsigned long flags;
 
-	spin_lock_irqsave(&anchor->lock, flags);
-	while (!list_empty(&anchor->urb_list)) {
-		victim = list_entry(anchor->urb_list.prev, struct urb,
-				    anchor_list);
-		usb_get_urb(victim);
-		spin_unlock_irqrestore(&anchor->lock, flags);
-		/* this will unanchor the URB */
+        while ((victim = usb_get_from_anchor(anchor)) != NULL) {
 		usb_unlink_urb(victim);
 		usb_put_urb(victim);
-		spin_lock_irqsave(&anchor->lock, flags);
 	}
-	spin_unlock_irqrestore(&anchor->lock, flags);
 }
 EXPORT_SYMBOL_GPL(usb_unlink_anchored_urbs);
 
@@ -878,13 +875,13 @@ struct urb *usb_get_from_anchor(struct usb_anchor *anchor)
 		victim = list_entry(anchor->urb_list.next, struct urb,
 				    anchor_list);
 		usb_get_urb(victim);
-		spin_unlock_irqrestore(&anchor->lock, flags);
-		usb_unanchor_urb(victim);
+		__usb_unanchor_urb(victim, anchor);
 	} else {
-		spin_unlock_irqrestore(&anchor->lock, flags);
 		victim = NULL;
 	}
 
+	spin_unlock_irqrestore(&anchor->lock, flags);
+
 	return victim;
 }
 
@@ -905,12 +902,7 @@ void usb_scuttle_anchored_urbs(struct usb_anchor *anchor)
 	while (!list_empty(&anchor->urb_list)) {
 		victim = list_entry(anchor->urb_list.prev, struct urb,
 				    anchor_list);
-		usb_get_urb(victim);
-		spin_unlock_irqrestore(&anchor->lock, flags);
-		/* this may free the URB */
-		usb_unanchor_urb(victim);
-		usb_put_urb(victim);
-		spin_lock_irqsave(&anchor->lock, flags);
+		__usb_unanchor_urb(victim, anchor);
 	}
 	spin_unlock_irqrestore(&anchor->lock, flags);
 }