diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index aded106620204..4b74bf86c74d8 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -186,14 +186,16 @@ efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
 		goto fail;
 
 	/*
-	 * Enforce minimum alignment that EFI requires when requesting
-	 * a specific address.  We are doing page-based allocations,
-	 * so we must be aligned to a page.
+	 * Enforce minimum alignment that EFI or Linux requires when
+	 * requesting a specific address.  We are doing page-based (or
+	 * larger) allocations, and both the address and size must meet
+	 * alignment constraints.
 	 */
 	if (align < EFI_ALLOC_ALIGN)
 		align = EFI_ALLOC_ALIGN;
 
-	nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
+	size = round_up(size, EFI_ALLOC_ALIGN);
+	nr_pages = size / EFI_PAGE_SIZE;
 again:
 	for (i = 0; i < map_size / desc_size; i++) {
 		efi_memory_desc_t *desc;
@@ -208,7 +210,7 @@ efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
 			continue;
 
 		start = desc->phys_addr;
-		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+		end = start + desc->num_pages * EFI_PAGE_SIZE;
 
 		if (end > max)
 			end = max;
@@ -278,14 +280,16 @@ efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
 		goto fail;
 
 	/*
-	 * Enforce minimum alignment that EFI requires when requesting
-	 * a specific address.  We are doing page-based allocations,
-	 * so we must be aligned to a page.
+	 * Enforce minimum alignment that EFI or Linux requires when
+	 * requesting a specific address.  We are doing page-based (or
+	 * larger) allocations, and both the address and size must meet
+	 * alignment constraints.
 	 */
 	if (align < EFI_ALLOC_ALIGN)
 		align = EFI_ALLOC_ALIGN;
 
-	nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
+	size = round_up(size, EFI_ALLOC_ALIGN);
+	nr_pages = size / EFI_PAGE_SIZE;
 	for (i = 0; i < map_size / desc_size; i++) {
 		efi_memory_desc_t *desc;
 		unsigned long m = (unsigned long)map;
@@ -300,7 +304,7 @@ efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
 			continue;
 
 		start = desc->phys_addr;
-		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+		end = start + desc->num_pages * EFI_PAGE_SIZE;
 
 		/*
 		 * Don't allocate at 0x0. It will confuse code that