Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/misc/cxl/main.c b/drivers/misc/cxl/main.c
index f35406b..43b312d 100644
--- a/drivers/misc/cxl/main.c
+++ b/drivers/misc/cxl/main.c
@@ -1,10 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright 2014 IBM Corp.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
  */
 
 #include <linux/spinlock.h>
@@ -22,6 +18,7 @@
 #include <linux/sched/task.h>
 
 #include <asm/cputable.h>
+#include <asm/mmu.h>
 #include <misc/cxl-base.h>
 
 #include "cxl.h"
@@ -319,6 +316,9 @@
 {
 	int rc = 0;
 
+	if (!tlbie_capable)
+		return -EINVAL;
+
 	if ((rc = cxl_file_init()))
 		return rc;