From: Ingo Molnar <mingo@elte.hu>
Date: Wed, 30 Jan 2008 12:33:23 +0000 (+0100)
Subject: x86: add debug of invalid per_cpu map accesses
X-Git-Tag: v2.6.25-rc1~1143^2~223
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5f5cd8fd60c71ce47d2ce4e60e7ccbc306e91c64;p=linux-2.6

x86: add debug of invalid per_cpu map accesses

dont crash survivable situations.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/include/asm-x86/topology.h b/include/asm-x86/topology.h
index f1e1232907..9a8228a177 100644
--- a/include/asm-x86/topology.h
+++ b/include/asm-x86/topology.h
@@ -66,14 +66,15 @@ static inline int early_cpu_to_node(int cpu)
 
 static inline int cpu_to_node(int cpu)
 {
-#ifdef	CONFIG_DEBUG_PER_CPU_MAPS
-	if(x86_cpu_to_node_map_early_ptr) {
+#ifdef CONFIG_DEBUG_PER_CPU_MAPS
+	if (x86_cpu_to_node_map_early_ptr) {
 		printk("KERN_NOTICE cpu_to_node(%d): usage too early!\n",
 			(int)cpu);
-		BUG();
+		dump_stack();
+		return ((int *)x86_cpu_to_node_map_early_ptr)[cpu];
 	}
 #endif
-	if(per_cpu_offset(cpu))
+	if (per_cpu_offset(cpu))
 		return per_cpu(x86_cpu_to_node_map, cpu);
 	else
 		return NUMA_NO_NODE;