From 9ea95f4ccbec05aea5365eed8e9eed09bd6e5bdf Mon Sep 17 00:00:00 2001
From: Mike Travis <travis@sgi.com>
Date: Fri, 27 Jun 2008 10:10:13 -0700
Subject: [PATCH] --- yaml --- r: 99988 b: refs/heads/master c:
 6a2f47ca27fad36f99e8478a3807d4b8c7db80e7 h: refs/heads/master v: v3

---
 [refs]                               |  2 +-
 trunk/arch/x86/kernel/setup_percpu.c | 26 +++++++++++++++++++++++---
 trunk/include/asm-x86/topology.h     |  7 ++++++-
 3 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/[refs] b/[refs]
index d9cbcb49367c..3acd167e476f 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: cd5dce2fb023a6f0168344b7dd8adec30017458e
+refs/heads/master: 6a2f47ca27fad36f99e8478a3807d4b8c7db80e7
diff --git a/trunk/arch/x86/kernel/setup_percpu.c b/trunk/arch/x86/kernel/setup_percpu.c
index 7068f95cccc6..43aca2de624a 100644
--- a/trunk/arch/x86/kernel/setup_percpu.c
+++ b/trunk/arch/x86/kernel/setup_percpu.c
@@ -346,6 +346,10 @@ int early_cpu_to_node(int cpu)
 	return per_cpu(x86_cpu_to_node_map, cpu);
 }
 
+
+/* empty cpumask */
+static const cpumask_t cpu_mask_none;
+
 /*
  * Returns a pointer to the bitmask of CPUs on Node 'node'.
  */
@@ -358,13 +362,23 @@ cpumask_t *_node_to_cpumask_ptr(int node)
 		dump_stack();
 		return &cpu_online_map;
 	}
-	BUG_ON(node >= nr_node_ids);
-	return &node_to_cpumask_map[node];
+	if (node >= nr_node_ids) {
+		printk(KERN_WARNING
+			"_node_to_cpumask_ptr(%d): node > nr_node_ids(%d)\n",
+			node, nr_node_ids);
+		dump_stack();
+		return (cpumask_t *)&cpu_mask_none;
+	}
+	return (cpumask_t *)&node_to_cpumask_map[node];
 }
 EXPORT_SYMBOL(_node_to_cpumask_ptr);
 
 /*
  * Returns a bitmask of CPUs on Node 'node'.
+ *
+ * Side note: this function creates the returned cpumask on the stack
+ * so with a high NR_CPUS count, excessive stack space is used.  The
+ * node_to_cpumask_ptr function should be used whenever possible.
  */
 cpumask_t node_to_cpumask(int node)
 {
@@ -374,7 +388,13 @@ cpumask_t node_to_cpumask(int node)
 		dump_stack();
 		return cpu_online_map;
 	}
-	BUG_ON(node >= nr_node_ids);
+	if (node >= nr_node_ids) {
+		printk(KERN_WARNING
+			"node_to_cpumask(%d): node > nr_node_ids(%d)\n",
+			node, nr_node_ids);
+		dump_stack();
+		return cpu_mask_none;
+	}
 	return node_to_cpumask_map[node];
 }
 EXPORT_SYMBOL(node_to_cpumask);
diff --git a/trunk/include/asm-x86/topology.h b/trunk/include/asm-x86/topology.h
index 1f97758de4ab..98e5f17ea856 100644
--- a/trunk/include/asm-x86/topology.h
+++ b/trunk/include/asm-x86/topology.h
@@ -57,7 +57,12 @@ static inline int cpu_to_node(int cpu)
 }
 #define early_cpu_to_node(cpu)	cpu_to_node(cpu)
 
-/* Returns a bitmask of CPUs on Node 'node'. */
+/* Returns a bitmask of CPUs on Node 'node'.
+ *
+ * Side note: this function creates the returned cpumask on the stack
+ * so with a high NR_CPUS count, excessive stack space is used.  The
+ * node_to_cpumask_ptr function should be used whenever possible.
+ */
 static inline cpumask_t node_to_cpumask(int node)
 {
 	return node_to_cpumask_map[node];