1 files changed, 24 insertions, 21 deletions

diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index de46b50f4cdf..4eeb17198cfa 100644
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -127,7 +127,11 @@ static int __init uefi_init(void)
 	table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables;
 	config_tables = early_memremap(efi_to_phys(efi.systab->tables),
 				       table_size);
-
+	if (config_tables == NULL) {
+		pr_warn("Unable to map EFI config table array.\n");
+		retval = -ENOMEM;
+		goto out;
+	}
 	retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables,
 					 sizeof(efi_config_table_64_t), NULL);
 
@@ -209,6 +213,14 @@ void __init efi_init(void)
 			 PAGE_ALIGN(params.mmap_size + (params.mmap & ~PAGE_MASK)));
 	memmap.phys_map = params.mmap;
 	memmap.map = early_memremap(params.mmap, params.mmap_size);
+	if (memmap.map == NULL) {
+		/*
+		* If we are booting via UEFI, the UEFI memory map is the only
+		* description of memory we have, so there is little point in
+		* proceeding if we cannot access it.
+		*/
+		panic("Unable to map EFI memory map.\n");
+	}
 	memmap.map_end = memmap.map + params.mmap_size;
 	memmap.desc_size = params.desc_size;
 	memmap.desc_version = params.desc_ver;
@@ -224,8 +236,9 @@ static bool __init efi_virtmap_init(void)
 {
 	efi_memory_desc_t *md;
 
+	init_new_context(NULL, &efi_mm);
+
 	for_each_efi_memory_desc(&memmap, md) {
-		u64 paddr, npages, size;
 		pgprot_t prot;
 
 		if (!(md->attribute & EFI_MEMORY_RUNTIME))
@@ -233,11 +246,6 @@ static bool __init efi_virtmap_init(void)
 		if (md->virt_addr == 0)
 			return false;
 
-		paddr = md->phys_addr;
-		npages = md->num_pages;
-		memrange_efi_to_native(&paddr, &npages);
-		size = npages << PAGE_SHIFT;
-
 		pr_info("  EFI remap 0x%016llx => %p\n",
 			md->phys_addr, (void *)md->virt_addr);
 
@@ -254,7 +262,9 @@ static bool __init efi_virtmap_init(void)
 		else
 			prot = PAGE_KERNEL;
 
-		create_pgd_mapping(&efi_mm, paddr, md->virt_addr, size, prot);
+		create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr,
+				   md->num_pages << EFI_PAGE_SHIFT, 
+				   __pgprot(pgprot_val(prot) | PTE_NG));
 	}
 	return true;
 }
@@ -270,12 +280,12 @@ static int __init arm64_enable_runtime_services(void)
 
 	if (!efi_enabled(EFI_BOOT)) {
 		pr_info("EFI services will not be available.\n");
-		return -1;
+		return 0;
 	}
 
 	if (efi_runtime_disabled()) {
 		pr_info("EFI runtime services will be disabled.\n");
-		return -1;
+		return 0;
 	}
 
 	pr_info("Remapping and enabling EFI services.\n");
@@ -285,7 +295,7 @@ static int __init arm64_enable_runtime_services(void)
 						   mapsize);
 	if (!memmap.map) {
 		pr_err("Failed to remap EFI memory map\n");
-		return -1;
+		return -ENOMEM;
 	}
 	memmap.map_end = memmap.map + mapsize;
 	efi.memmap = &memmap;
@@ -294,13 +304,13 @@ static int __init arm64_enable_runtime_services(void)
 						   sizeof(efi_system_table_t));
 	if (!efi.systab) {
 		pr_err("Failed to remap EFI System Table\n");
-		return -1;
+		return -ENOMEM;
 	}
 	set_bit(EFI_SYSTEM_TABLES, &efi.flags);
 
 	if (!efi_virtmap_init()) {
 		pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n");
-		return -1;
+		return -ENOMEM;
 	}
 
 	/* Set up runtime services function pointers */
@@ -329,14 +339,7 @@ core_initcall(arm64_dmi_init);
 
 static void efi_set_pgd(struct mm_struct *mm)
 {
-	if (mm == &init_mm)
-		cpu_set_reserved_ttbr0();
-	else
-		cpu_switch_mm(mm->pgd, mm);
-
-	local_flush_tlb_all();
-	if (icache_is_aivivt())
-		__local_flush_icache_all();
+	switch_mm(NULL, mm, NULL);
 }
 
 void efi_virtmap_load(void)