diff --git a/[refs] b/[refs]
index 0ff3fd3796d5..ed29e3dd53f4 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 220bf991b0366cc50a94feede3d7341fa5710ee4
+refs/heads/master: a90110c61073eab95d1986322693c2b9a8a6a5f6
diff --git a/trunk/arch/x86/kernel/cpu/perf_event_amd.c b/trunk/arch/x86/kernel/cpu/perf_event_amd.c
index 573458f1caf2..b87e0b6970cb 100644
--- a/trunk/arch/x86/kernel/cpu/perf_event_amd.c
+++ b/trunk/arch/x86/kernel/cpu/perf_event_amd.c
@@ -348,10 +348,12 @@ static void amd_pmu_cpu_offline(int cpu)
 
 	raw_spin_lock(&amd_nb_lock);
 
-	if (--cpuhw->amd_nb->refcnt == 0)
-		kfree(cpuhw->amd_nb);
+	if (cpuhw->amd_nb) {
+		if (--cpuhw->amd_nb->refcnt == 0)
+			kfree(cpuhw->amd_nb);
 
-	cpuhw->amd_nb = NULL;
+		cpuhw->amd_nb = NULL;
+	}
 
 	raw_spin_unlock(&amd_nb_lock);
 }