x86/efi: Make efi virtual runtime map passing more robust

[mirror_ubuntu-bionic-kernel.git] / arch / x86 / platform / efi / efi_64.c

diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 6284f158a47d851b1f4a0ca3f951e20ac5c3ffd7..19280900ec25e63b3a02b9c90e3371f81858bdfe 100644 (file)
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -137,12 +137,38 @@ void efi_sync_low_kernel_mappings(void)
                sizeof(pgd_t) * num_pgds);
 }
 
-void efi_setup_page_tables(void)
+int efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 {
+       pgd_t *pgd;
+
+       if (efi_enabled(EFI_OLD_MEMMAP))
+               return 0;
+
        efi_scratch.efi_pgt = (pgd_t *)(unsigned long)real_mode_header->trampoline_pgd;
+       pgd = __va(efi_scratch.efi_pgt);
 
-       if (!efi_enabled(EFI_OLD_MEMMAP))
-               efi_scratch.use_pgd = true;
+       /*
+        * It can happen that the physical address of new_memmap lands in memory
+        * which is not mapped in the EFI page table. Therefore we need to go
+        * and ident-map those pages containing the map before calling
+        * phys_efi_set_virtual_address_map().
+        */
+       if (kernel_map_pages_in_pgd(pgd, pa_memmap, pa_memmap, num_pages, _PAGE_NX)) {
+               pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap);
+               return 1;
+       }
+
+       efi_scratch.use_pgd = true;
+
+
+       return 0;
+}
+
+void efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages)
+{
+       pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd);
+
+       kernel_unmap_pages_in_pgd(pgd, pa_memmap, num_pages);
 }
 
 static void __init __map_region(efi_memory_desc_t *md, u64 va)
@@ -233,3 +259,21 @@ void __init parse_efi_setup(u64 phys_addr, u32 data_len)
 {
        efi_setup = phys_addr + sizeof(struct setup_data);
 }
+
+void __init efi_runtime_mkexec(void)
+{
+       if (!efi_enabled(EFI_OLD_MEMMAP))
+               return;
+
+       if (__supported_pte_mask & _PAGE_NX)
+               runtime_code_page_mkexec();
+}
+
+void __init efi_dump_pagetable(void)
+{
+#ifdef CONFIG_EFI_PGT_DUMP
+       pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd);
+
+       ptdump_walk_pgd_level(NULL, pgd);
+#endif
+}