Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 3c0e470..417ff64 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -1,11 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
  */
 
 #include <linux/stddef.h>
 #include <linux/module.h>
-#include <linux/bootmem.h>
+#include <linux/memblock.h>
 #include <linux/highmem.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
@@ -31,6 +31,7 @@
 
 /* Initialized at boot time, and readonly after that */
 unsigned long long highmem;
+EXPORT_SYMBOL(highmem);
 int kmalloc_ok = 0;
 
 /* Used during early boot */
@@ -46,13 +47,13 @@
 	 */
 	brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
 	map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
-	free_bootmem(__pa(brk_end), uml_reserved - brk_end);
+	memblock_free(__pa(brk_end), uml_reserved - brk_end);
 	uml_reserved = brk_end;
 
 	/* this will put all low memory onto the freelists */
-	free_all_bootmem();
-	max_low_pfn = totalram_pages;
-	max_pfn = totalram_pages;
+	memblock_free_all();
+	max_low_pfn = totalram_pages();
+	max_pfn = max_low_pfn;
 	mem_init_print_info(NULL);
 	kmalloc_ok = 1;
 }
@@ -64,7 +65,12 @@
 static void __init one_page_table_init(pmd_t *pmd)
 {
 	if (pmd_none(*pmd)) {
-		pte_t *pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+		pte_t *pte = (pte_t *) memblock_alloc_low(PAGE_SIZE,
+							  PAGE_SIZE);
+		if (!pte)
+			panic("%s: Failed to allocate %lu bytes align=%lx\n",
+			      __func__, PAGE_SIZE, PAGE_SIZE);
+
 		set_pmd(pmd, __pmd(_KERNPG_TABLE +
 					   (unsigned long) __pa(pte)));
 		if (pte != pte_offset_kernel(pmd, 0))
@@ -75,7 +81,11 @@
 static void __init one_md_table_init(pud_t *pud)
 {
 #ifdef CONFIG_3_LEVEL_PGTABLES
-	pmd_t *pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+	pmd_t *pmd_table = (pmd_t *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
+	if (!pmd_table)
+		panic("%s: Failed to allocate %lu bytes align=%lx\n",
+		      __func__, PAGE_SIZE, PAGE_SIZE);
+
 	set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
 	if (pmd_table != pmd_offset(pud, 0))
 		BUG();
@@ -124,7 +134,11 @@
 		return;
 
 	fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
-	v = (unsigned long) alloc_bootmem_low_pages(size);
+	v = (unsigned long) memblock_alloc_low(size, PAGE_SIZE);
+	if (!v)
+		panic("%s: Failed to allocate %lu bytes align=%lx\n",
+		      __func__, size, PAGE_SIZE);
+
 	memcpy((void *) v , (void *) FIXADDR_USER_START, size);
 	p = __pa(v);
 	for ( ; size > 0; size -= PAGE_SIZE, vaddr += PAGE_SIZE,
@@ -143,7 +157,12 @@
 	unsigned long zones_size[MAX_NR_ZONES], vaddr;
 	int i;
 
-	empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
+	empty_zero_page = (unsigned long *) memblock_alloc_low(PAGE_SIZE,
+							       PAGE_SIZE);
+	if (!empty_zero_page)
+		panic("%s: Failed to allocate %lu bytes align=%lx\n",
+		      __func__, PAGE_SIZE, PAGE_SIZE);
+
 	for (i = 0; i < ARRAY_SIZE(zones_size); i++)
 		zones_size[i] = 0;
 
@@ -170,13 +189,6 @@
 {
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /* Allocate and free page tables. */
 
 pgd_t *pgd_alloc(struct mm_struct *mm)
@@ -197,28 +209,6 @@
 	free_page((unsigned long) pgd);
 }
 
-pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
-{
-	pte_t *pte;
-
-	pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
-	return pte;
-}
-
-pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
-{
-	struct page *pte;
-
-	pte = alloc_page(GFP_KERNEL|__GFP_ZERO);
-	if (!pte)
-		return NULL;
-	if (!pgtable_page_ctor(pte)) {
-		__free_page(pte);
-		return NULL;
-	}
-	return pte;
-}
-
 #ifdef CONFIG_3_LEVEL_PGTABLES
 pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
 {