Index: linux-2.6/include/linux/mmu_notifier.h
===================================================================
--- linux-2.6.orig/include/linux/mmu_notifier.h	2008-01-24 13:48:48.000000000 -0800
+++ linux-2.6/include/linux/mmu_notifier.h	2008-01-24 14:05:04.000000000 -0800
@@ -3,6 +3,7 @@
 
 #include <linux/list.h>
 #include <linux/spinlock.h>
+#include <linux/rcupdate.h>
 
 #ifdef CONFIG_MMU_NOTIFIER
 
@@ -24,7 +25,6 @@ struct mmu_notifier_ops {
 
 struct mmu_notifier_head {
 	struct hlist_head head;
-	rwlock_t lock;
 };
 
 struct mmu_notifier {
@@ -45,7 +45,6 @@ extern int mmu_notifier_age_page(struct 
 static inline void mmu_notifier_head_init(struct mmu_notifier_head *mnh)
 {
 	INIT_HLIST_HEAD(&mnh->head);
-	rwlock_init(&mnh->lock);
 }
 
 #define mmu_notifier(function, mm, args...)				\
@@ -54,15 +53,15 @@ static inline void mmu_notifier_head_ini
 		struct hlist_node *__n;					\
 									\
 		if (unlikely(!hlist_empty(&(mm)->mmu_notifier.head))) { \
-			read_lock(&(mm)->mmu_notifier.lock);		\
-			hlist_for_each_entry(__mn, __n,			\
+			rcu_read_lock();				\
+			hlist_for_each_entry_rcu(__mn, __n,		\
 					     &(mm)->mmu_notifier.head,	\
 					     hlist)			\
 				if (__mn->ops->function)		\
 					__mn->ops->function(__mn,	\
 							    mm,		\
 							    args);	\
-			read_unlock(&(mm)->mmu_notifier.lock);		\
+			rcu_read_unlock();				\
 		}							\
 	} while (0)
 
Index: linux-2.6/mm/mmu_notifier.c
===================================================================
--- linux-2.6.orig/mm/mmu_notifier.c	2008-01-24 13:47:20.000000000 -0800
+++ linux-2.6/mm/mmu_notifier.c	2008-01-24 14:16:49.000000000 -0800
@@ -13,17 +13,17 @@
 void mmu_notifier_release(struct mm_struct *mm)
 {
 	struct mmu_notifier *mn;
-	struct hlist_node *n, *tmp;
+	struct hlist_node *n;
 
 	if (unlikely(!hlist_empty(&mm->mmu_notifier.head))) {
-		read_lock(&mm->mmu_notifier.lock);
-		hlist_for_each_entry_safe(mn, n, tmp,
+		rcu_read_lock();
+		hlist_for_each_entry_rcu(mn, n,
 					  &mm->mmu_notifier.head, hlist) {
 			if (mn->ops->release)
 				mn->ops->release(mn, mm);
 			hlist_del(&mn->hlist);
 		}
-		read_unlock(&mm->mmu_notifier.lock);
+		rcu_read_unlock();
 	}
 }
 
@@ -35,17 +35,17 @@ void mmu_notifier_release(struct mm_stru
 int mmu_notifier_age_page(struct mm_struct *mm, unsigned long address)
 {
 	struct mmu_notifier *mn;
-	struct hlist_node *n, *tmp;
+	struct hlist_node *n;
 	int young = 0;
 
 	if (unlikely(!hlist_empty(&mm->mmu_notifier.head))) {
-		read_lock(&mm->mmu_notifier.lock);
-		hlist_for_each_entry_safe(mn, n, tmp,
+		rcu_read_lock();
+		hlist_for_each_entry_rcu(mn, n,
 					  &mm->mmu_notifier.head, hlist) {
 			if (mn->ops->age_page)
 				young |= mn->ops->age_page(mn, mm, address);
 		}
-		read_unlock(&mm->mmu_notifier.lock);
+		rcu_read_unlock();
 	}
 
 	return young;
@@ -53,16 +53,12 @@ int mmu_notifier_age_page(struct mm_stru
 
 void mmu_notifier_register(struct mmu_notifier *mn, struct mm_struct *mm)
 {
-	write_lock(&mm->mmu_notifier.lock);
 	hlist_add_head(&mn->hlist, &mm->mmu_notifier.head);
-	write_unlock(&mm->mmu_notifier.lock);
 }
 EXPORT_SYMBOL_GPL(mmu_notifier_register);
 
 void mmu_notifier_unregister(struct mmu_notifier *mn, struct mm_struct *mm)
 {
-	write_lock(&mm->mmu_notifier.lock);
 	hlist_del(&mn->hlist);
-	write_unlock(&mm->mmu_notifier.lock);
 }
 EXPORT_SYMBOL_GPL(mmu_notifier_unregister);