From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: [patch 03/18] x86: pvclock: make sure rdtsc doesnt speculate out of region
Date: Mon, 19 Nov 2012 19:58:01 -0200
Message-ID: <20121119215958.796614150@redhat.com>
References: <20121119215758.686768790@redhat.com>
Cc: johnstul@us.ibm.com, jeremy@goop.org, glommer@parallels.com,
	Marcelo Tosatti <mtosatti@redhat.com>
To: mingo@kernel.org, kvm@vger.kernel.org
Return-path: <kvm-owner@vger.kernel.org>
Received: from mx1.redhat.com ([209.132.183.28]:5945 "EHLO mx1.redhat.com"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1752321Ab2KSV63 (ORCPT <rfc822;kvm@vger.kernel.org>);
	Mon, 19 Nov 2012 16:58:29 -0500
Content-Disposition: inline; filename=01-pvclock-read-rdtsc-barrier
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

Originally from Jeremy Fitzhardinge.

pvclock_get_time_values, which contains the memory barriers
will be removed by next patch.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Index: vsyscall/arch/x86/kernel/pvclock.c
===================================================================
--- vsyscall.orig/arch/x86/kernel/pvclock.c
+++ vsyscall/arch/x86/kernel/pvclock.c
@@ -97,10 +97,10 @@ cycle_t pvclock_clocksource_read(struct 
 
 	do {
 		version = pvclock_get_time_values(&shadow, src);
-		barrier();
+		rdtsc_barrier();
 		offset = pvclock_get_nsec_offset(&shadow);
 		ret = shadow.system_timestamp + offset;
-		barrier();
+		rdtsc_barrier();
 	} while (version != src->version);
 
 	if ((valid_flags & PVCLOCK_TSC_STABLE_BIT) &&