[PATCH] Fix topology.c location

When compiling a non-default subarch, topology.c is missing from the kernel
build.  This causes builds with CONFIG_HOTPLUG_CPU to fail.  In addition,
on Intel processors with cpuid level > 4, it causes intel_cacheinfo.c to
reference uninitialized data that should have been set up by the initcall
in topology.c which calls register_cpu.  This causes a kernel panic on boot
on newer Intel processors.  Moving topology.c to arch/i386/kernel fixes
both of these problems.

Thanks to Dan Hecht for finding and fixing this problem.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Dan Hecht <dhect@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 98 insertions, 1 deletions

diff --git a/arch/i386/kernel/Makefile b/arch/i386/kernel/Makefile
index 60c3f76dfca..53bb9a79e27 100644
--- a/arch/i386/kernel/Makefile
+++ b/arch/i386/kernel/Makefile
@@ -7,7 +7,7 @@ extra-y := head.o init_task.o vmlinux.lds
 obj-y	:= process.o semaphore.o signal.o entry.o traps.o irq.o \
 		ptrace.o time.o ioport.o ldt.o setup.o i8259.o sys_i386.o \
 		pci-dma.o i386_ksyms.o i387.o dmi_scan.o bootflag.o \
-		quirks.o i8237.o
+		quirks.o i8237.o topology.o
 
 obj-y				+= cpu/
 obj-y				+= timers/
diff --git a/arch/i386/kernel/topology.c b/arch/i386/kernel/topology.c
new file mode 100644
index 00000000000..67a0e1baa28
--- /dev/null
+++ b/arch/i386/kernel/topology.c
@@ -0,0 +1,97 @@
+/*
+ * arch/i386/kernel/topology.c - Populate driverfs with topology information
+ *
+ * Written by: Matthew Dobson, IBM Corporation
+ * Original Code: Paul Dorwin, IBM Corporation, Patrick Mochel, OSDL
+ *
+ * Copyright (C) 2002, IBM Corp.
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Send feedback to <colpatch@us.ibm.com>
+ */
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/nodemask.h>
+#include <asm/cpu.h>
+
+static struct i386_cpu cpu_devices[NR_CPUS];
+
+int arch_register_cpu(int num){
+	struct node *parent = NULL;
+
+#ifdef CONFIG_NUMA
+	int node = cpu_to_node(num);
+	if (node_online(node))
+		parent = &node_devices[node].node;
+#endif /* CONFIG_NUMA */
+
+	return register_cpu(&cpu_devices[num].cpu, num, parent);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+void arch_unregister_cpu(int num) {
+	struct node *parent = NULL;
+
+#ifdef CONFIG_NUMA
+	int node = cpu_to_node(num);
+	if (node_online(node))
+		parent = &node_devices[node].node;
+#endif /* CONFIG_NUMA */
+
+	return unregister_cpu(&cpu_devices[num].cpu, parent);
+}
+EXPORT_SYMBOL(arch_register_cpu);
+EXPORT_SYMBOL(arch_unregister_cpu);
+#endif /*CONFIG_HOTPLUG_CPU*/
+
+
+
+#ifdef CONFIG_NUMA
+#include <linux/mmzone.h>
+#include <asm/node.h>
+
+struct i386_node node_devices[MAX_NUMNODES];
+
+static int __init topology_init(void)
+{
+	int i;
+
+	for_each_online_node(i)
+		arch_register_node(i);
+
+	for_each_present_cpu(i)
+		arch_register_cpu(i);
+	return 0;
+}
+
+#else /* !CONFIG_NUMA */
+
+static int __init topology_init(void)
+{
+	int i;
+
+	for_each_present_cpu(i)
+		arch_register_cpu(i);
+	return 0;
+}
+
+#endif /* CONFIG_NUMA */
+
+subsys_initcall(topology_init);