linux-kernel - [1/2 -tip, BUG-fix] x86-microcode: fix unbalanced use of get

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Date:	Wed, 20 Aug 2008 00:16:13 +0200
From:	Dmitry Adamushko <dmitry.adamushko@...il.com>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	Peter Oruba <peter.oruba@....com>,
	Tigran Aivazian <tigran@...azian.fsnet.co.uk>,
	Max Krasnyansky <maxk@...lcomm.com>,
	LKML <linux-kernel@...r.kernel.org>
Subject: [1/2 -tip, BUG-fix] x86-microcode: fix unbalanced use of get_cpu()


From: Dmitry Adamushko <dmitry.adamushko@...il.com>

Subject: x86-microcode: fix unbalanced use of get_cpu()

Don't use get_cpu() at all. Resort to checking a boot-up CPU (#0) in
microcode_{intel,amd}_module_init().

---

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@...il.com>


commit 9375be36d98cdaecefbd98904609f1aee0d50367
Author: dimm <dimm@...th.(none)>
Date:   Tue Aug 19 22:40:41 2008 +0200

    microcode: bug-fix

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 33b2a21..a6e76cc 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -500,13 +500,15 @@ static struct microcode_ops microcode_amd_ops = {
 
 static int __init microcode_amd_module_init(void)
 {
-	struct cpuinfo_x86 *c = &cpu_data(get_cpu());
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
 	equiv_cpu_table = NULL;
-	if (c->x86_vendor == X86_VENDOR_AMD)
-		return microcode_init(&microcode_amd_ops, THIS_MODULE);
-	else
+	if (c->x86_vendor != X86_VENDOR_AMD) {
+		printk(KERN_ERR "microcode: CPU platform is not AMD-capable\n");
 		return -ENODEV;
+	}
+
+	return microcode_init(&microcode_amd_ops, THIS_MODULE);
 }
 
 static void __exit microcode_amd_module_exit(void)
diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index d2d9d74..6dd8907 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -531,12 +531,14 @@ static struct microcode_ops microcode_intel_ops = {
 
 static int __init microcode_intel_module_init(void)
 {
-	struct cpuinfo_x86 *c = &cpu_data(get_cpu());
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
-	if (c->x86_vendor == X86_VENDOR_INTEL)
-		return microcode_init(&microcode_intel_ops, THIS_MODULE);
-	else
+	if (c->x86_vendor != X86_VENDOR_INTEL) {
+                printk(KERN_ERR "microcode: CPU platform is not Intel-capable\n");
 		return -ENODEV;
+	}
+
+	return microcode_init(&microcode_intel_ops, THIS_MODULE);
 }
 
 static void __exit microcode_intel_module_exit(void)


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