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>
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 322b24f..af6cf2b 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -728,6 +728,17 @@
#ifdef CONFIG_X86_32
memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
visws_early_detect();
+
+ /*
+ * copy kernel address range established so far and switch
+ * to the proper swapper page table
+ */
+ clone_pgd_range(swapper_pg_dir + KERNEL_PGD_BOUNDARY,
+ initial_page_table + KERNEL_PGD_BOUNDARY,
+ KERNEL_PGD_PTRS);
+
+ load_cr3(swapper_pg_dir);
+ __flush_tlb_all();
#else
printk(KERN_INFO "Command line: %s\n", boot_command_line);
#endif
@@ -1009,7 +1020,12 @@
paging_init();
x86_init.paging.pagetable_setup_done(swapper_pg_dir);
- setup_trampoline_page_table();
+#ifdef CONFIG_X86_32
+ /* sync back kernel address range */
+ clone_pgd_range(initial_page_table + KERNEL_PGD_BOUNDARY,
+ swapper_pg_dir + KERNEL_PGD_BOUNDARY,
+ KERNEL_PGD_PTRS);
+#endif
tboot_probe();