diff --git a/[refs] b/[refs]
index d999fab4f23b..c8bd4701f4f9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c3e228d59bd2054fd57f7f146ef0f6fb0e1996b7
+refs/heads/master: e2b297fcf17fc03734e93387fb8195c782286b35
diff --git a/trunk/arch/x86/kernel/cpu/perf_event.c b/trunk/arch/x86/kernel/cpu/perf_event.c
index 000a4746c7ce..766c76d5ec4c 100644
--- a/trunk/arch/x86/kernel/cpu/perf_event.c
+++ b/trunk/arch/x86/kernel/cpu/perf_event.c
@@ -1640,7 +1640,12 @@ static ssize_t set_attr_rdpmc(struct device *cdev,
 			      struct device_attribute *attr,
 			      const char *buf, size_t count)
 {
-	unsigned long val = simple_strtoul(buf, NULL, 0);
+	unsigned long val;
+	ssize_t ret;
+
+	ret = kstrtoul(buf, 0, &val);
+	if (ret)
+		return ret;
 
 	if (!!val != !!x86_pmu.attr_rdpmc) {
 		x86_pmu.attr_rdpmc = !!val;