Merge branch 'core-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 EFI update from Peter Anvin:
 "EFI tree, from Matt Fleming.  Most of the patches are the new efivarfs
  filesystem by Matt Garrett & co.  The balance are support for EFI
  wallclock in the absence of a hardware-specific driver, and various
  fixes and cleanups."

* 'core-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  efivarfs: Make efivarfs_fill_super() static
  x86, efi: Check table header length in efi_bgrt_init()
  efivarfs: Use query_variable_info() to limit kmalloc()
  efivarfs: Fix return value of efivarfs_file_write()
  efivarfs: Return a consistent error when efivarfs_get_inode() fails
  efivarfs: Make 'datasize' unsigned long
  efivarfs: Add unique magic number
  efivarfs: Replace magic number with sizeof(attributes)
  efivarfs: Return an error if we fail to read a variable
  efi: Clarify GUID length calculations
  efivarfs: Implement exclusive access for {get,set}_variable
  efivarfs: efivarfs_fill_super() ensure we clean up correctly on error
  efivarfs: efivarfs_fill_super() ensure we free our temporary name
  efivarfs: efivarfs_fill_super() fix inode reference counts
  efivarfs: efivarfs_create() ensure we drop our reference on inode on error
  efivarfs: efivarfs_file_read ensure we free data in error paths
  x86-64/efi: Use EFI to deal with platform wall clock (again)
  x86/kernel: remove tboot 1:1 page table creation code
  x86, efi: 1:1 pagetable mapping for virtual EFI calls
  x86, mm: Include the entire kernel memory map in trampoline_pgd
  ...

1 files changed, 15 insertions, 2 deletions

diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
index cbca565af5bd..8e6ab6137852 100644
--- a/arch/x86/realmode/init.c
+++ b/arch/x86/realmode/init.c
@@ -78,8 +78,21 @@ void __init setup_real_mode(void)
 	*trampoline_cr4_features = read_cr4();
 
 	trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd);
-	trampoline_pgd[0] = __pa(level3_ident_pgt) + _KERNPG_TABLE;
-	trampoline_pgd[511] = __pa(level3_kernel_pgt) + _KERNPG_TABLE;
+
+	/*
+	 * Create an identity mapping for all of physical memory.
+	 */
+	for (i = 0; i <= pgd_index(max_pfn << PAGE_SHIFT); i++) {
+		int index = pgd_index(PAGE_OFFSET) + i;
+
+		trampoline_pgd[i] = (u64)pgd_val(swapper_pg_dir[index]);
+	}
+
+	/*
+	 * Copy the upper-half of the kernel pages tables.
+	 */
+	for (i = pgd_index(PAGE_OFFSET); i < PTRS_PER_PGD; i++)
+		trampoline_pgd[i] = (u64)pgd_val(swapper_pg_dir[i]);
 #endif
 }