From 16430b12a31872d4db5200fc9be804323bca892f Mon Sep 17 00:00:00 2001
From: Xin LI <delphij@FreeBSD.org>
Date: Fri, 30 Jul 2010 21:39:28 +0000
Subject: [PATCH] In rdmsr_safe, use zero extend (by doing a 32-bit movl over
 eax to itself) instead of a sign extend.

Discussed with:	stas
MFC after:	1 month
---
 sys/amd64/amd64/support.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/amd64/amd64/support.S b/sys/amd64/amd64/support.S
index b445ceef8b4..ab45e56a05f 100644
--- a/sys/amd64/amd64/support.S
+++ b/sys/amd64/amd64/support.S
@@ -729,7 +729,7 @@ ENTRY(rdmsr_safe)
 	rdmsr			/* Read MSR pointed by %ecx. Returns
 				   hi byte in edx, lo in %eax */
 	salq	$32,%rdx	/* sign-shift %rdx left */
-	cltq			/* sign-extend %eax -> %rax */
+	movl	%eax,%eax	/* zero-extend %eax -> %rax */
 	orq	%rdx,%rax
 	movq	%rax,(%rsi)
 	xorq	%rax,%rax