3 files changed, 54 insertions, 3 deletions

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 605e5ae..b9ca498 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -910,6 +910,13 @@ void __init setup_arch(char **cmdline_p)
 	memblock.current_limit = get_max_mapped();
 	memblock_x86_fill();
 
+	/*
+	 * The EFI specification says that boot service code won't be called
+	 * after ExitBootServices(). This is, in fact, a lie.
+	 */
+	if (efi_enabled)
+		efi_reserve_boot_services();
+
 	/* preallocate 4k for mptable mpc */
 	early_reserve_e820_mpc_new();
 
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index b30aa26..0d3a4fa 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -304,6 +304,40 @@ static void __init print_efi_memmap(void)
 }
 #endif  /*  EFI_DEBUG  */
 
+void __init efi_reserve_boot_services(void)
+{
+	void *p;
+
+	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+		efi_memory_desc_t *md = p;
+		unsigned long long start = md->phys_addr;
+		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
+
+		if (md->type != EFI_BOOT_SERVICES_CODE &&
+		    md->type != EFI_BOOT_SERVICES_DATA)
+			continue;
+
+		memblock_x86_reserve_range(start, start + size, "EFI Boot");
+	}
+}
+
+static void __init efi_free_boot_services(void)
+{
+	void *p;
+
+	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+		efi_memory_desc_t *md = p;
+		unsigned long long start = md->phys_addr;
+		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
+
+		if (md->type != EFI_BOOT_SERVICES_CODE &&
+		    md->type != EFI_BOOT_SERVICES_DATA)
+			continue;
+
+		free_bootmem_late(start, size);
+	}
+}
+
 void __init efi_init(void)
 {
 	efi_config_table_t *config_tables;
@@ -536,7 +570,9 @@ void __init efi_enter_virtual_mode(void)
 
 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 		md = p;
-		if (!(md->attribute & EFI_MEMORY_RUNTIME))
+		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
+		    md->type != EFI_BOOT_SERVICES_CODE &&
+		    md->type != EFI_BOOT_SERVICES_DATA)
 			continue;
 
 		size = md->num_pages << EFI_PAGE_SHIFT;
@@ -593,6 +629,13 @@ void __init efi_enter_virtual_mode(void)
 	}
 
 	/*
+	 * Thankfully, it does seem that no runtime services other than
+	 * SetVirtualAddressMap() will touch boot services code, so we can
+	 * get rid of it all at this point
+	 */
+	efi_free_boot_services();
+
+	/*
 	 * Now that EFI is in virtual mode, update the function
 	 * pointers in the runtime service table to the new virtual addresses.
 	 *
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 2649426..ac3aa54 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -49,10 +49,11 @@ static void __init early_code_mapping_set_exec(int executable)
 	if (!(__supported_pte_mask & _PAGE_NX))
 		return;
 
-	/* Make EFI runtime service code area executable */
+	/* Make EFI service code area executable */
 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 		md = p;
-		if (md->type == EFI_RUNTIME_SERVICES_CODE)
+		if (md->type == EFI_RUNTIME_SERVICES_CODE ||
+		    md->type == EFI_BOOT_SERVICES_CODE)
 			efi_set_executable(md, executable);
 	}
 }