diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index df393eab0e50..6f499819a27f 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -119,11 +119,10 @@ void efi_get_time(struct timespec *now)
 
 void __init efi_find_mirror(void)
 {
-	void *p;
+	efi_memory_desc_t *md;
 	u64 mirror_size = 0, total_size = 0;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		efi_memory_desc_t *md = p;
+	for_each_efi_memory_desc(md) {
 		unsigned long long start = md->phys_addr;
 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 
@@ -146,10 +145,9 @@ void __init efi_find_mirror(void)
 
 static void __init do_add_efi_memmap(void)
 {
-	void *p;
+	efi_memory_desc_t *md;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		efi_memory_desc_t *md = p;
+	for_each_efi_memory_desc(md) {
 		unsigned long long start = md->phys_addr;
 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 		int e820_type;
@@ -226,17 +224,13 @@ void __init efi_print_memmap(void)
 {
 #ifdef EFI_DEBUG
 	efi_memory_desc_t *md;
-	void *p;
-	int i;
+	int i = 0;
 
-	for (p = memmap.map, i = 0;
-	     p < memmap.map_end;
-	     p += memmap.desc_size, i++) {
+	for_each_efi_memory_desc(md) {
 		char buf[64];
 
-		md = p;
 		pr_info("mem%02u: %s range=[0x%016llx-0x%016llx] (%lluMB)\n",
-			i, efi_md_typeattr_format(buf, sizeof(buf), md),
+			i++, efi_md_typeattr_format(buf, sizeof(buf), md),
 			md->phys_addr,
 			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1,
 			(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
@@ -550,12 +544,9 @@ void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 void __init runtime_code_page_mkexec(void)
 {
 	efi_memory_desc_t *md;
-	void *p;
 
 	/* Make EFI runtime service code area executable */
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		md = p;
-
+	for_each_efi_memory_desc(md) {
 		if (md->type != EFI_RUNTIME_SERVICES_CODE)
 			continue;
 
@@ -602,12 +593,10 @@ void __init old_map_region(efi_memory_desc_t *md)
 /* Merge contiguous regions of the same type and attribute */
 static void __init efi_merge_regions(void)
 {
-	void *p;
 	efi_memory_desc_t *md, *prev_md = NULL;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+	for_each_efi_memory_desc(md) {
 		u64 prev_size;
-		md = p;
 
 		if (!prev_md) {
 			prev_md = md;
@@ -650,15 +639,13 @@ static void __init save_runtime_map(void)
 {
 #ifdef CONFIG_KEXEC_CORE
 	efi_memory_desc_t *md;
-	void *tmp, *p, *q = NULL;
+	void *tmp, *q = NULL;
 	int count = 0;
 
 	if (efi_enabled(EFI_OLD_MEMMAP))
 		return;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		md = p;
-
+	for_each_efi_memory_desc(md) {
 		if (!(md->attribute & EFI_MEMORY_RUNTIME) ||
 		    (md->type == EFI_BOOT_SERVICES_CODE) ||
 		    (md->type == EFI_BOOT_SERVICES_DATA))
@@ -814,7 +801,6 @@ static void __init kexec_enter_virtual_mode(void)
 #ifdef CONFIG_KEXEC_CORE
 	efi_memory_desc_t *md;
 	unsigned int num_pages;
-	void *p;
 
 	efi.systab = NULL;
 
@@ -838,8 +824,7 @@ static void __init kexec_enter_virtual_mode(void)
 	* Map efi regions which were passed via setup_data. The virt_addr is a
 	* fixed addr which was used in first kernel of a kexec boot.
 	*/
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		md = p;
+	for_each_efi_memory_desc(md) {
 		efi_map_region_fixed(md); /* FIXME: add error handling */
 		get_systab_virt_addr(md);
 	}
@@ -1009,13 +994,11 @@ void __init efi_enter_virtual_mode(void)
 u32 efi_mem_type(unsigned long phys_addr)
 {
 	efi_memory_desc_t *md;
-	void *p;
 
 	if (!efi_enabled(EFI_MEMMAP))
 		return 0;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		md = p;
+	for_each_efi_memory_desc(md) {
 		if ((md->phys_addr <= phys_addr) &&
 		    (phys_addr < (md->phys_addr +
 				  (md->num_pages << EFI_PAGE_SHIFT))))
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 49e4dd4a1f58..6e7242be1c87 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -55,14 +55,12 @@ struct efi_scratch efi_scratch;
 static void __init early_code_mapping_set_exec(int executable)
 {
 	efi_memory_desc_t *md;
-	void *p;
 
 	if (!(__supported_pte_mask & _PAGE_NX))
 		return;
 
 	/* Make EFI service code area executable */
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		md = p;
+	for_each_efi_memory_desc(md) {
 		if (md->type == EFI_RUNTIME_SERVICES_CODE ||
 		    md->type == EFI_BOOT_SERVICES_CODE)
 			efi_set_executable(md, executable);
@@ -253,7 +251,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 	 * Map all of RAM so that we can access arguments in the 1:1
 	 * mapping when making EFI runtime calls.
 	 */
-	for_each_efi_memory_desc(&memmap, md) {
+	for_each_efi_memory_desc(md) {
 		if (md->type != EFI_CONVENTIONAL_MEMORY &&
 		    md->type != EFI_LOADER_DATA &&
 		    md->type != EFI_LOADER_CODE)
@@ -398,7 +396,6 @@ void __init efi_runtime_update_mappings(void)
 	unsigned long pfn;
 	pgd_t *pgd = efi_pgd;
 	efi_memory_desc_t *md;
-	void *p;
 
 	if (efi_enabled(EFI_OLD_MEMMAP)) {
 		if (__supported_pte_mask & _PAGE_NX)
@@ -409,9 +406,8 @@ void __init efi_runtime_update_mappings(void)
 	if (!efi_enabled(EFI_NX_PE_DATA))
 		return;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+	for_each_efi_memory_desc(md) {
 		unsigned long pf = 0;
-		md = p;
 
 		if (!(md->attribute & EFI_MEMORY_RUNTIME))
 			continue;
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index ab50ada1d56e..097cb09d917b 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -195,10 +195,9 @@ static bool can_free_region(u64 start, u64 size)
 */
 void __init efi_reserve_boot_services(void)
 {
-	void *p;
+	efi_memory_desc_t *md;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		efi_memory_desc_t *md = p;
+	for_each_efi_memory_desc(md) {
 		u64 start = md->phys_addr;
 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
 		bool already_reserved;
@@ -250,10 +249,9 @@ void __init efi_reserve_boot_services(void)
 
 void __init efi_free_boot_services(void)
 {
-	void *p;
+	efi_memory_desc_t *md;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		efi_memory_desc_t *md = p;
+	for_each_efi_memory_desc(md) {
 		unsigned long long start = md->phys_addr;
 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 
diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c
index 008ed1993b72..d5f6b0ca521e 100644
--- a/drivers/firmware/efi/arm-init.c
+++ b/drivers/firmware/efi/arm-init.c
@@ -40,7 +40,7 @@ static phys_addr_t efi_to_phys(unsigned long addr)
 {
 	efi_memory_desc_t *md;
 
-	for_each_efi_memory_desc(&memmap, md) {
+	for_each_efi_memory_desc_in_map(&memmap, md) {
 		if (!(md->attribute & EFI_MEMORY_RUNTIME))
 			continue;
 		if (md->virt_addr == 0)
@@ -145,7 +145,7 @@ static __init void reserve_regions(void)
 	if (efi_enabled(EFI_DBG))
 		pr_info("Processing EFI memory map:\n");
 
-	for_each_efi_memory_desc(&memmap, md) {
+	for_each_efi_memory_desc_in_map(&memmap, md) {
 		paddr = md->phys_addr;
 		npages = md->num_pages;
 
diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
index 771750df6b7d..1cfbfaf57a2d 100644
--- a/drivers/firmware/efi/arm-runtime.c
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -48,7 +48,7 @@ static bool __init efi_virtmap_init(void)
 	init_new_context(NULL, &efi_mm);
 
 	systab_found = false;
-	for_each_efi_memory_desc(&memmap, md) {
+	for_each_efi_memory_desc(md) {
 		phys_addr_t phys = md->phys_addr;
 		int ret;
 
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 3a69ed5ecfcb..4b533ce73374 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -620,16 +620,12 @@ char * __init efi_md_typeattr_format(char *buf, size_t size,
  */
 u64 __weak efi_mem_attributes(unsigned long phys_addr)
 {
-	struct efi_memory_map *map;
 	efi_memory_desc_t *md;
-	void *p;
 
 	if (!efi_enabled(EFI_MEMMAP))
 		return 0;
 
-	map = efi.memmap;
-	for (p = map->map; p < map->map_end; p += map->desc_size) {
-		md = p;
+	for_each_efi_memory_desc(md) {
 		if ((md->phys_addr <= phys_addr) &&
 		    (phys_addr < (md->phys_addr +
 		    (md->num_pages << EFI_PAGE_SHIFT))))
diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
index ed3a854950cc..f55b75b2e1f4 100644
--- a/drivers/firmware/efi/fake_mem.c
+++ b/drivers/firmware/efi/fake_mem.c
@@ -68,8 +68,7 @@ void __init efi_fake_memmap(void)
 		return;
 
 	/* count up the number of EFI memory descriptor */
-	for (old = memmap.map; old < memmap.map_end; old += memmap.desc_size) {
-		md = old;
+	for_each_efi_memory_desc(md) {
 		start = md->phys_addr;
 		end = start + (md->num_pages << EFI_PAGE_SHIFT) - 1;
 
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 29ed2f9b218c..3bd127f95315 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -125,10 +125,12 @@ unsigned long get_dram_base(efi_system_table_t *sys_table_arg)
 
 	map.map_end = map.map + map_size;
 
-	for_each_efi_memory_desc(&map, md)
-		if (md->attribute & EFI_MEMORY_WB)
+	for_each_efi_memory_desc_in_map(&map, md) {
+		if (md->attribute & EFI_MEMORY_WB) {
 			if (membase > md->phys_addr)
 				membase = md->phys_addr;
+		}
+	}
 
 	efi_call_early(free_pool, map.map);
 
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 1545098b0565..17ef4471e603 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -958,11 +958,20 @@ static inline void efi_fake_memmap(void) { }
 #endif
 
 /* Iterate through an efi_memory_map */
-#define for_each_efi_memory_desc(m, md)					   \
+#define for_each_efi_memory_desc_in_map(m, md)				   \
 	for ((md) = (m)->map;						   \
 	     (md) <= (efi_memory_desc_t *)((m)->map_end - (m)->desc_size); \
 	     (md) = (void *)(md) + (m)->desc_size)
 
+/**
+ * for_each_efi_memory_desc - iterate over descriptors in efi.memmap
+ * @md: the efi_memory_desc_t * iterator
+ *
+ * Once the loop finishes @md must not be accessed.
+ */
+#define for_each_efi_memory_desc(md) \
+	for_each_efi_memory_desc_in_map(efi.memmap, md)
+
 /*
  * Format an EFI memory descriptor's type and attributes to a user-provided
  * character buffer, as per snprintf(), and return the buffer.