--- 22cf21e9e792a2c70713427f2a224301e2313c10
+++ 6dc4e5ef7a01aab7e92479455c3672ce6096461c
@@ -369,18 +369,11 @@ static int function_stat_show(struct seq
 {
 	struct ftrace_profile *rec = v;
 	char str[KSYM_SYMBOL_LEN];
-	int ret = 0;
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
+	static DEFINE_MUTEX(mutex);
 	static struct trace_seq s;
 	unsigned long long avg;
 #endif
-	mutex_lock(&ftrace_profile_lock);
-
-	/* we raced with function_profile_reset() */
-	if (unlikely(rec->counter == 0)) {
-		ret = -EBUSY;
-		goto out;
-	}
 
 	kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
 	seq_printf(m, "  %-30.30s  %10lu", str, rec->counter);
@@ -390,17 +383,17 @@ static int function_stat_show(struct seq
 	avg = rec->time;
 	do_div(avg, rec->counter);
 
+	mutex_lock(&mutex);
 	trace_seq_init(&s);
 	trace_print_graph_duration(rec->time, &s);
 	trace_seq_puts(&s, "    ");
 	trace_print_graph_duration(avg, &s);
 	trace_print_seq(m, &s);
+	mutex_unlock(&mutex);
 #endif
 	seq_putc(m, '\n');
-out:
-	mutex_unlock(&ftrace_profile_lock);
 
-	return ret;
+	return 0;
 }
 
 static void ftrace_profile_reset(struct ftrace_profile_stat *stat)
@@ -1480,8 +1473,6 @@ static void *t_start(struct seq_file *m,
 		if (*pos > 0)
 			return t_hash_start(m, pos);
 		iter->flags |= FTRACE_ITER_PRINTALL;
-		/* reset in case of seek/pread */
-		iter->flags &= ~FTRACE_ITER_HASH;
 		return iter;
 	}
 
@@ -2402,7 +2393,7 @@ static const struct file_operations ftra
 	.open = ftrace_filter_open,
 	.read = seq_read,
 	.write = ftrace_filter_write,
-	.llseek = no_llseek,
+	.llseek = ftrace_regex_lseek,
 	.release = ftrace_filter_release,
 };
 
@@ -3267,7 +3258,6 @@ void ftrace_graph_init_task(struct task_
 {
 	/* Make sure we do not use the parent ret_stack */
 	t->ret_stack = NULL;
-	t->curr_ret_stack = -1;
 
 	if (ftrace_graph_active) {
 		struct ftrace_ret_stack *ret_stack;
@@ -3277,6 +3267,7 @@ void ftrace_graph_init_task(struct task_
 				GFP_KERNEL);
 		if (!ret_stack)
 			return;
+		t->curr_ret_stack = -1;
 		atomic_set(&t->tracing_graph_pause, 0);
 		atomic_set(&t->trace_overrun, 0);
 		t->ftrace_timestamp = 0;