Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index 582cb15..484d95a 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -1,22 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
  *                    <benh@kernel.crashing.org>
  * Copyright (C) 2012 ARM Limited
  * Copyright (C) 2015 Regents of the University of California
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/elf.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/binfmts.h>
@@ -36,7 +26,7 @@
 	struct vdso_data	data;
 	u8			page[PAGE_SIZE];
 } vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = &vdso_data_store.data;
+static struct vdso_data *vdso_data = &vdso_data_store.data;
 
 static int __init vdso_init(void)
 {
@@ -54,7 +44,6 @@
 		struct page *pg;
 
 		pg = virt_to_page(vdso_start + (i << PAGE_SHIFT));
-		ClearPageReserved(pg);
 		vdso_pagelist[i] = pg;
 	}
 	vdso_pagelist[i] = virt_to_page(vdso_data);
@@ -104,22 +93,3 @@
 		return "[vdso]";
 	return NULL;
 }
-
-/*
- * Function stubs to prevent linker errors when AT_SYSINFO_EHDR is defined
- */
-
-int in_gate_area_no_mm(unsigned long addr)
-{
-	return 0;
-}
-
-int in_gate_area(struct mm_struct *mm, unsigned long addr)
-{
-	return 0;
-}
-
-struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
-{
-	return NULL;
-}