Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
index 922add8..0df8493 100644
--- a/arch/arm64/kernel/machine_kexec.c
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -1,12 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * kexec for arm64
  *
  * Copyright (C) Linaro.
  * Copyright (C) Huawei Futurewei Technologies.
- *
- * 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.
  */
 
 #include <linux/interrupt.h>
@@ -212,9 +209,17 @@
 	 * uses physical addressing to relocate the new image to its final
 	 * position and transfers control to the image entry point when the
 	 * relocation is complete.
+	 * In kexec case, kimage->start points to purgatory assuming that
+	 * kernel entry and dtb address are embedded in purgatory by
+	 * userspace (kexec-tools).
+	 * In kexec_file case, the kernel starts directly without purgatory.
 	 */
-
-	cpu_soft_restart(reboot_code_buffer_phys, kimage->head, kimage->start, 0);
+	cpu_soft_restart(reboot_code_buffer_phys, kimage->head, kimage->start,
+#ifdef CONFIG_KEXEC_FILE
+						kimage->arch.dtb_mem);
+#else
+						0);
+#endif
 
 	BUG(); /* Should never get here. */
 }
@@ -313,7 +318,7 @@
  * but does not hold any data of loaded kernel image.
  *
  * Note that all the pages in crash dump kernel memory have been initially
- * marked as Reserved in kexec_reserve_crashkres_pages().
+ * marked as Reserved as memory was allocated via memblock_reserve().
  *
  * In hibernation, the pages which are Reserved and yet "nosave" are excluded
  * from the hibernation iamge. crash_is_nosave() does thich check for crash
@@ -353,7 +358,6 @@
 
 	for (addr = begin; addr < end; addr += PAGE_SIZE) {
 		page = phys_to_page(addr);
-		ClearPageReserved(page);
 		free_reserved_page(page);
 	}
 }