Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: more general identifier for Phoenix BIOS
  AMD IOMMU: check for next_bit also in unmapped area
  AMD IOMMU: fix fullflush comparison length
  AMD IOMMU: enable device isolation per default
  AMD IOMMU: add parameter to disable device isolation
  x86, PEBS/DS: fix code flow in ds_request()
  x86: add rdtsc barrier to TSC sync check
  xen: fix scrub_page()
  x86: fix es7000 compiling
  x86, bts: fix unlock problem in ds.c
  x86, voyager: fix smp generic helper voyager breakage
  x86: move iomap.h to the new include location

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86/kernel/tsc_sync.c b/arch/x86/kernel/tsc_sync.c
index 9ffb01c31c40..1c0dfbca87c1 100644
--- a/arch/x86/kernel/tsc_sync.c
+++ b/arch/x86/kernel/tsc_sync.c
@@ -46,7 +46,9 @@ static __cpuinit void check_tsc_warp(void)
 	cycles_t start, now, prev, end;
 	int i;
 
+	rdtsc_barrier();
 	start = get_cycles();
+	rdtsc_barrier();
 	/*
 	 * The measurement runs for 20 msecs:
 	 */
@@ -61,7 +63,9 @@ static __cpuinit void check_tsc_warp(void)
 		 */
 		__raw_spin_lock(&sync_lock);
 		prev = last_tsc;
+		rdtsc_barrier();
 		now = get_cycles();
+		rdtsc_barrier();
 		last_tsc = now;
 		__raw_spin_unlock(&sync_lock);