Commit b40827fa authored by Borislav Petkov's avatar Borislav Petkov Committed by H. Peter Anvin
Browse files

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: default avatarBorislav Petkov <bp@alien8.de>
LKML-Reference: <20101020070526.GA9588@liondog.tnic>
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent d25e6b0b

arch/x86/include/asm/pgtable_32.h

+1 −1
Original line number Diff line number Diff line
@@ -26,7 +26,7 @@ struct mm_struct; 
struct vm_area_struct;



extern pgd_t swapper_pg_dir[1024];

extern pgd_t trampoline_pg_dir[1024];

extern pgd_t initial_page_table[1024];



static inline void pgtable_cache_init(void) { }

static inline void check_pgt_cache(void) { }

arch/x86/include/asm/tlbflush.h

+0 −2
Original line number Diff line number Diff line
@@ -172,6 +172,4 @@ static inline void flush_tlb_kernel_range(unsigned long start, 
	flush_tlb_all();

}



extern void zap_low_mappings(bool early);



#endif /* _ASM_X86_TLBFLUSH_H */

arch/x86/include/asm/trampoline.h

+0 −3
Original line number Diff line number Diff line
@@ -13,16 +13,13 @@ extern unsigned char *trampoline_base; 


extern unsigned long init_rsp;

extern unsigned long initial_code;

extern unsigned long initial_page_table;

extern unsigned long initial_gs;



#define TRAMPOLINE_SIZE roundup(trampoline_end - trampoline_data, PAGE_SIZE)



extern unsigned long setup_trampoline(void);

extern void __init setup_trampoline_page_table(void);

extern void __init reserve_trampoline_memory(void);

#else

static inline void setup_trampoline_page_table(void) {}

static inline void reserve_trampoline_memory(void) {}

#endif /* CONFIG_X86_TRAMPOLINE */

arch/x86/kernel/acpi/sleep.c

+6 −1
Original line number Diff line number Diff line
@@ -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;

arch/x86/kernel/head32.c

+1 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include <asm/apic.h>

#include <asm/io_apic.h>

#include <asm/bios_ebda.h>

#include <asm/tlbflush.h>



static void __init i386_default_early_setup(void)

{

CRA Git | Maintained and supported by SUSTech CRA and CCSE