x86: EFI runtime code mapping enhancement
This patch enhances EFI runtime code memory mapping as following:
- Move __supported_pte_mask & _PAGE_NX checking before invoking
runtime_code_page_mkexec(). This makes it possible for compiler to
eliminate runtime_code_page_mkexec() on machine without NX support.
- Use set_memory_x/nx in early_mapping_set_exec(). This eliminates the
duplicated implementation.
This patch has been tested on Intel x86_64 platform with EFI64/32
firmware.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/efi.c b/arch/x86/kernel/efi.c
index b4d5232..cbdf9ba 100644
--- a/arch/x86/kernel/efi.c
+++ b/arch/x86/kernel/efi.c
@@ -384,9 +384,6 @@
efi_memory_desc_t *md;
void *p;
- if (!(__supported_pte_mask & _PAGE_NX))
- return;
-
/* Make EFI runtime service code area executable */
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
md = p;
@@ -476,7 +473,8 @@
efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
efi.reset_system = virt_efi_reset_system;
efi.set_virtual_address_map = virt_efi_set_virtual_address_map;
- runtime_code_page_mkexec();
+ if (__supported_pte_mask & _PAGE_NX)
+ runtime_code_page_mkexec();
early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
memmap.map = NULL;
}