From 26bd1da8f2147731c66b2c1cc5225812e0b5b521 Mon Sep 17 00:00:00 2001
From: Yinghai Lu <Yinghai.Lu@Sun.COM>
Date: Sat, 23 Feb 2008 21:48:42 -0800
Subject: [PATCH] --- yaml --- r: 88637 b: refs/heads/master c:
 322850af8d93735f67b8ebf84bb1350639be3f34 h: refs/heads/master i:   88635:
 cc2d41eba029005f870d291f038cc03e50c342bf v: v3

---
 [refs]                          |  2 +-
 trunk/arch/x86/kernel/apic_64.c | 12 +++++++++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index b049c91a5614..45530e6a2109 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 513ad84bf60d96a6998bca10ed07c3d340449be8
+refs/heads/master: 322850af8d93735f67b8ebf84bb1350639be3f34
diff --git a/trunk/arch/x86/kernel/apic_64.c b/trunk/arch/x86/kernel/apic_64.c
index d8d03e09dea2..7d8ffdaa0ab3 100644
--- a/trunk/arch/x86/kernel/apic_64.c
+++ b/trunk/arch/x86/kernel/apic_64.c
@@ -1180,9 +1180,19 @@ __cpuinit int apic_is_clustered_box(void)
 {
 	int i, clusters, zeros;
 	unsigned id;
-	u16 *bios_cpu_apicid = x86_bios_cpu_apicid_early_ptr;
+	u16 *bios_cpu_apicid;
 	DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
 
+	/*
+	 * there is not this kind of box with AMD CPU yet.
+	 * Some AMD box with quadcore cpu and 8 sockets apicid
+	 * will be [4, 0x23] or [8, 0x27] could be thought to
+	 * have three apic_clusters. So go out early.
+	 */
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+		return 0;
+
+	bios_cpu_apicid = x86_bios_cpu_apicid_early_ptr;
 	bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
 
 	for (i = 0; i < NR_CPUS; i++) {