From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: [patch 02/15] x86: pvclock: make sure rdtsc doesnt speculate out of region
Date: Tue, 16 Oct 2012 14:56:21 -0300
Message-ID: <20121016180137.372927096@redhat.com>
References: <20121016175619.194848607@redhat.com>
Cc: johnstul@us.ibm.com, jeremy@goop.org,
	Marcelo Tosatti <mtosatti@redhat.com>
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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) &&