diff -Nru a/arch/ppc64/kernel/prom.c b/arch/ppc64/kernel/prom.c
--- a/arch/ppc64/kernel/prom.c	Mon Nov 24 22:35:28 2003
+++ b/arch/ppc64/kernel/prom.c	Mon Nov 24 22:35:28 2003
@@ -1618,6 +1618,8 @@
 		mem_start = DOUBLEWORD_ALIGN(mem_start + l + 1);
 	}

+	spin_lock_init(&np->properties_lock);
+
 	/* do all our children */
 	child = call_prom(RELOC("child"), 1, 1, node);
 	while (child != (phandle)0) {
@@ -2455,6 +2457,7 @@
 	}
 	strcpy(np->full_name, path);

+	spin_lock_init(&np->properties_lock);
 	np->properties = proplist;
 	OF_MARK_DYNAMIC(np);
 	of_node_get(np);
@@ -2535,6 +2538,26 @@
 	}
 	write_unlock(&devtree_lock);
 	of_node_put(parent);
+	return 0;
+}
+
+/*
+ * Add a property to a device_node, adding an entry in /proc/device-tree
+ * if appropriate.
+ */
+int of_add_property(struct device_node *np, struct property *pp)
+{
+	unsigned long flags;
+
+	if (np->pde && !proc_device_tree_add_property(np->pde, pp))
+		return -ENOMEM;
+
+	spin_lock_irqsave(&np->properties_lock, flags);
+	pp->next = np->properties;
+	wmb(); /* prevents us from dying in get_property for now */
+	np->properties = pp;
+	spin_unlock_irqrestore(&np->properties_lock, flags);
+
 	return 0;
 }

diff -Nru a/fs/proc/proc_devtree.c b/fs/proc/proc_devtree.c
--- a/fs/proc/proc_devtree.c	Mon Nov 24 22:35:28 2003
+++ b/fs/proc/proc_devtree.c	Mon Nov 24 22:35:28 2003
@@ -26,6 +26,24 @@
 #endif

 static struct proc_dir_entry *proc_device_tree;
+static int property_read_proc(char *, char **, off_t, int, int *, void *);
+
+struct proc_dir_entry *proc_device_tree_add_property(struct proc_dir_entry *de, struct property *pp)
+{
+	struct proc_dir_entry *ent;
+
+	ent = create_proc_read_entry(pp->name, strncmp(pp->name, "security-", 9) ? S_IRUGO : S_IRUSR, de, property_read_proc, pp);
+
+	if (!ent)
+		return NULL;
+
+	if (!strncmp(pp->name, "security-", 9))
+		ent->size = 0; /* don't leak number of password chars */
+	else
+		ent->size = pp->length;
+
+	return ent;
+}

 /*
  * Supply data on a read from /proc/device-tree/node/property.
@@ -74,14 +92,9 @@
 		 * Unfortunately proc_register puts each new entry
 		 * at the beginning of the list.  So we rearrange them.
 		 */
-		ent = create_proc_read_entry(pp->name, strncmp(pp->name, "security-", 9) ?
-					     S_IRUGO : S_IRUSR, de, property_read_proc, pp);
+		ent = proc_device_tree_add_property(de, pp);
 		if (ent == 0)
 			break;
-		if (!strncmp(pp->name, "security-", 9))
-		     ent->size = 0; /* don't leak number of password chars */
-		else
-		     ent->size = pp->length;
 		*lastp = ent;
 		lastp = &ent->next;
 	}
diff -Nru a/include/asm-ppc64/prom.h b/include/asm-ppc64/prom.h
--- a/include/asm-ppc64/prom.h	Mon Nov 24 22:35:28 2003
+++ b/include/asm-ppc64/prom.h	Mon Nov 24 22:35:28 2003
@@ -16,6 +16,7 @@
  */
 #include <linux/proc_fs.h>
 #include <asm/atomic.h>
+#include <asm/spinlock.h>

 #define PTRRELOC(x)     ((typeof(x))((unsigned long)(x) - offset))
 #define PTRUNRELOC(x)   ((typeof(x))((unsigned long)(x) + offset))
@@ -151,6 +152,7 @@
 	struct  pci_controller *phb;	/* for pci devices */
 	struct	TceTable *tce_table;	/* for phb's or bridges */

+	spinlock_t properties_lock;     /* for traversal of properties list */
 	struct	property *properties;
 	struct	device_node *parent;
 	struct	device_node *child;
@@ -229,6 +231,7 @@
 extern struct device_node *find_compatible_devices(const char *type,
 						   const char *compat);
 extern struct device_node *find_all_nodes(void);
+extern void prom_add_property(struct device_node* np, struct property* prop);

 /* New style node lookup */
 extern struct device_node *of_find_node_by_name(struct device_node *from,
@@ -248,6 +251,7 @@
 /* For updating the device tree at runtime */
 extern int of_add_node(const char *path, struct property *proplist);
 extern int of_remove_node(struct device_node *np);
+extern int of_add_property(struct device_node *np, struct property *pp);

 /* Other Prototypes */
 extern unsigned long prom_init(unsigned long, unsigned long, unsigned long,
@@ -263,6 +267,5 @@
 extern int prom_n_addr_cells(struct device_node* np);
 extern int prom_n_size_cells(struct device_node* np);
 extern void prom_get_irq_senses(unsigned char *senses, int off, int max);
-extern void prom_add_property(struct device_node* np, struct property* prop);

 #endif /* _PPC64_PROM_H */
diff -Nru a/include/linux/proc_fs.h b/include/linux/proc_fs.h
--- a/include/linux/proc_fs.h	Mon Nov 24 22:35:28 2003
+++ b/include/linux/proc_fs.h	Mon Nov 24 22:35:28 2003
@@ -131,9 +131,11 @@
 /*
  * proc_devtree.c
  */
+struct property;
 struct device_node;
 extern void proc_device_tree_init(void);
 extern void proc_device_tree_add_node(struct device_node *, struct proc_dir_entry *);
+extern struct proc_dir_entry * proc_device_tree_add_property(struct proc_dir_entry *, struct property *);

 /*
  * proc_rtas.c