Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 3d37c27..8310587 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * linux/kernel/power/snapshot.c
  *
@@ -5,9 +6,6 @@
  *
  * Copyright (C) 1998-2005 Pavel Machek <pavel@ucw.cz>
  * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
- *
- * This file is released under the GPLv2.
- *
  */
 
 #define pr_fmt(fmt) "PM: " fmt
@@ -23,7 +21,7 @@
 #include <linux/pm.h>
 #include <linux/device.h>
 #include <linux/init.h>
-#include <linux/bootmem.h>
+#include <linux/memblock.h>
 #include <linux/nmi.h>
 #include <linux/syscalls.h>
 #include <linux/console.h>
@@ -105,7 +103,7 @@
 
 void __init hibernate_image_size_init(void)
 {
-	image_size = ((totalram_pages * 2) / 5) * PAGE_SIZE;
+	image_size = ((totalram_pages() * 2) / 5) * PAGE_SIZE;
 }
 
 /*
@@ -963,7 +961,11 @@
 		BUG_ON(!region);
 	} else {
 		/* This allocation cannot fail */
-		region = memblock_virt_alloc(sizeof(struct nosave_region), 0);
+		region = memblock_alloc(sizeof(struct nosave_region),
+					SMP_CACHE_BYTES);
+		if (!region)
+			panic("%s: Failed to allocate %zu bytes\n", __func__,
+			      sizeof(struct nosave_region));
 	}
 	region->start_pfn = start_pfn;
 	region->end_pfn = end_pfn;
@@ -1214,14 +1216,16 @@
 	if (!pfn_valid(pfn))
 		return NULL;
 
-	page = pfn_to_page(pfn);
-	if (page_zone(page) != zone)
+	page = pfn_to_online_page(pfn);
+	if (!page || page_zone(page) != zone)
 		return NULL;
 
 	BUG_ON(!PageHighMem(page));
 
-	if (swsusp_page_is_forbidden(page) ||  swsusp_page_is_free(page) ||
-	    PageReserved(page))
+	if (swsusp_page_is_forbidden(page) ||  swsusp_page_is_free(page))
+		return NULL;
+
+	if (PageReserved(page) || PageOffline(page))
 		return NULL;
 
 	if (page_is_guard(page))
@@ -1276,8 +1280,8 @@
 	if (!pfn_valid(pfn))
 		return NULL;
 
-	page = pfn_to_page(pfn);
-	if (page_zone(page) != zone)
+	page = pfn_to_online_page(pfn);
+	if (!page || page_zone(page) != zone)
 		return NULL;
 
 	BUG_ON(PageHighMem(page));
@@ -1285,6 +1289,9 @@
 	if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page))
 		return NULL;
 
+	if (PageOffline(page))
+		return NULL;
+
 	if (PageReserved(page)
 	    && (!kernel_page_present(page) || pfn_is_nosave(pfn)))
 		return NULL;
@@ -1333,8 +1340,9 @@
  * safe_copy_page - Copy a page in a safe way.
  *
  * Check if the page we are going to copy is marked as present in the kernel
- * page tables (this always is the case if CONFIG_DEBUG_PAGEALLOC is not set
- * and in that case kernel_page_present() always returns 'true').
+ * page tables. This always is the case if CONFIG_DEBUG_PAGEALLOC or
+ * CONFIG_ARCH_HAS_SET_DIRECT_MAP is not set. In that case kernel_page_present()
+ * always returns 'true'.
  */
 static void safe_copy_page(void *dst, struct page *s_page)
 {