x86-32, mm: Add an initial page table for core bootstrapping

This patch adds an initial page table with low mappings used exclusively
for booting APs/resuming after ACPI suspend/machine restart. After this,
there's no need to add low mappings to swapper_pg_dir and zap them later
or create own swsusp PGD page solely for ACPI sleep needs - we have
initial_page_table for that.

Signed-off-by: Borislav Petkov <bp@alien8.de>
LKML-Reference: <20101020070526.GA9588@liondog.tnic>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index 33cec152070d..b35e1ab8ba03 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -12,6 +12,11 @@
 #include <asm/segment.h>
 #include <asm/desc.h>
 
+#ifdef CONFIG_X86_32
+#include <asm/pgtable.h>
+#include <asm/pgtable_32.h>
+#endif
+
 #include "realmode/wakeup.h"
 #include "sleep.h"
 
@@ -90,7 +95,7 @@ int acpi_save_state_mem(void)
 
 #ifndef CONFIG_64BIT
         header->pmode_entry = (u32)&wakeup_pmode_return;
-        header->pmode_cr3 = (u32)(swsusp_pg_dir - __PAGE_OFFSET);
+        header->pmode_cr3 = (u32)__pa(&initial_page_table);
         saved_magic = 0x12345678;
 #else /* CONFIG_64BIT */
         header->trampoline_segment = setup_trampoline() >> 4;