releases/2.6.21.2/sparc64-fix-recursion-in-prom-tree-building.patch

From stable-bounces@linux.kernel.org  Tue May 15 01:40:55 2007
Date: Tue, 15 May 2007 01:39:05 -0700 (PDT)
Message-Id: <20070515.013905.77057238.davem@davemloft.net>
To: stable@kernel.org
From: David Miller <davem@davemloft.net>
Cc: bunk@stusta.de
Subject: SPARC64: Fix recursion in PROM tree building.

Use iteration for scanning of PROM node siblings.

Based upon a patch by Greg Onufer, who found this bug.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

---
 arch/sparc64/kernel/prom.c |   19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

--- linux-2.6.21.1.orig/arch/sparc64/kernel/prom.c
+++ linux-2.6.21.1/arch/sparc64/kernel/prom.c
@@ -1555,10 +1555,21 @@ static struct device_node * __init creat
 
 static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp)
 {
+	struct device_node *ret = NULL, *prev_sibling = NULL;
 	struct device_node *dp;
 
-	dp = create_node(node, parent);
-	if (dp) {
+	while (1) {
+		dp = create_node(node, parent);
+		if (!dp)
+			break;
+
+		if (prev_sibling)
+			prev_sibling->sibling = dp;
+
+		if (!ret)
+			ret = dp;
+		prev_sibling = dp;
+
 		*(*nextp) = dp;
 		*nextp = &dp->allnext;
 
@@ -1567,10 +1578,10 @@ static struct device_node * __init build
 
 		dp->child = build_tree(dp, prom_getchild(node), nextp);
 
-		dp->sibling = build_tree(parent, prom_getsibling(node), nextp);
+		node = prom_getsibling(node);
 	}
 
-	return dp;
+	return ret;
 }
 
 void __init prom_build_devicetree(void)