diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 076718a7b3eaa20c6e9bfdde07d03b5e77f71d64..94971708ff7130b444c73e7e4e116ad815767ba2 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1171,8 +1171,9 @@ static char *get_kernel_version(const char *root_dir)
 	if (!file)
 		return NULL;
 
-	version[0] = '\0';
 	tmp = fgets(version, sizeof(version), file);
+	if (!tmp)
+		*version = '\0';
 	fclose(file);
 
 	name = strstr(version, prefix);