diff --git a/[refs] b/[refs]
index 9e84c1f53fc4..750c76327489 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6a0f03e0d35c10e07f1160ca75fc9a367931e38b
+refs/heads/master: c36cd16f78a5dd740a619ef8445e35a73484d58b
diff --git a/trunk/arch/x86_64/kernel/pmtimer.c b/trunk/arch/x86_64/kernel/pmtimer.c
index 5c51d10408a6..ee5ee4891f3d 100644
--- a/trunk/arch/x86_64/kernel/pmtimer.c
+++ b/trunk/arch/x86_64/kernel/pmtimer.c
@@ -86,7 +86,7 @@ static unsigned pmtimer_wait_tick(void)
 	for (a = b = inl(pmtmr_ioport) & ACPI_PM_MASK;
 	     a == b;
 	     b = inl(pmtmr_ioport) & ACPI_PM_MASK)
-		;
+		cpu_relax();
 	return b;
 }
 
@@ -97,6 +97,7 @@ void pmtimer_wait(unsigned us)
 	a = pmtimer_wait_tick();
 	do {
 		b = inl(pmtmr_ioport);
+		cpu_relax();
 	} while (cyc2us(b - a) < us);
 }