Index: linux-2.6/mm/hugetlb.c
===================================================================
--- linux-2.6.orig/mm/hugetlb.c	2006-12-04 10:17:35.000000000 -0800
+++ linux-2.6/mm/hugetlb.c	2006-12-04 10:21:58.000000000 -0800
@@ -466,6 +466,9 @@
 	struct page *page;
 	struct address_space *mapping;
 	pte_t new_pte;
+	static DEFINE_MUTEX(hugetlb_instantiation_mutex);
+
+	mutex_lock(&hugetlb_instantiation_mutex);
 
 	mapping = vma->vm_file->f_mapping;
 	idx = ((address - vma->vm_start) >> HPAGE_SHIFT)
@@ -528,6 +531,7 @@
 	spin_unlock(&mm->page_table_lock);
 	unlock_page(page);
 out:
+	mutex_unlock(&hugetlb_instantiation_mutex);
 	return ret;
 
 backout:
@@ -544,7 +548,6 @@
 	pte_t *ptep;
 	pte_t entry;
 	int ret;
-	static DEFINE_MUTEX(hugetlb_instantiation_mutex);
 
 	ptep = huge_pte_alloc(mm, address);
 	if (!ptep)
@@ -555,11 +558,9 @@
 	 * get spurious allocation failures if two CPUs race to instantiate
 	 * the same page in the page cache.
 	 */
-	mutex_lock(&hugetlb_instantiation_mutex);
 	entry = *ptep;
 	if (pte_none(entry)) {
 		ret = hugetlb_no_page(mm, vma, address, ptep, write_access);
-		mutex_unlock(&hugetlb_instantiation_mutex);
 		return ret;
 	}
 
@@ -571,7 +572,6 @@
 		if (write_access && !pte_write(entry))
 			ret = hugetlb_cow(mm, vma, address, ptep, entry);
 	spin_unlock(&mm->page_table_lock);
-	mutex_unlock(&hugetlb_instantiation_mutex);
 
 	return ret;
 }