Merge branch 'x86-trampoline-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-trampoline-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Fix binutils-2.21 symbol related build failures
  x86-64, trampoline: Remove unused variable
  x86, reboot: Fix the use of passed arguments in 32-bit BIOS reboot
  x86, reboot: Move the real-mode reboot code to an assembly file
  x86: Make the GDT_ENTRY() macro in <asm/segment.h> safe for assembly
  x86, trampoline: Use the unified trampoline setup for ACPI wakeup
  x86, trampoline: Common infrastructure for low memory trampolines

Fix up trivial conflicts in arch/x86/kernel/Makefile
This commit is contained in:
Linus Torvalds 2011-03-16 10:10:02 -07:00
commit e7fd3b4669
25 changed files with 313 additions and 278 deletions

View File

@ -221,10 +221,6 @@ config X86_HT
def_bool y
depends on SMP
config X86_TRAMPOLINE
def_bool y
depends on SMP || (64BIT && ACPI_SLEEP)
config X86_32_LAZY_GS
def_bool y
depends on X86_32 && !CC_STACKPROTECTOR

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@ -29,6 +29,7 @@
#include <asm/processor.h>
#include <asm/mmu.h>
#include <asm/mpspec.h>
#include <asm/trampoline.h>
#define COMPILER_DEPENDENT_INT64 long long
#define COMPILER_DEPENDENT_UINT64 unsigned long long
@ -117,7 +118,8 @@ static inline void acpi_disable_pci(void)
extern int acpi_save_state_mem(void);
extern void acpi_restore_state_mem(void);
extern unsigned long acpi_wakeup_address;
extern const unsigned char acpi_wakeup_code[];
#define acpi_wakeup_address (__pa(TRAMPOLINE_SYM(acpi_wakeup_code)))
/* early initialization routine */
extern void acpi_reserve_wakeup_memory(void);

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@ -18,7 +18,10 @@ extern struct machine_ops machine_ops;
void native_machine_crash_shutdown(struct pt_regs *regs);
void native_machine_shutdown(void);
void machine_real_restart(const unsigned char *code, int length);
void machine_real_restart(unsigned int type);
/* These must match dispatch_table in reboot_32.S */
#define MRR_BIOS 0
#define MRR_APM 1
typedef void (*nmi_shootdown_cb)(int, struct die_args*);
void nmi_shootdown_cpus(nmi_shootdown_cb callback);

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@ -1,14 +1,16 @@
#ifndef _ASM_X86_SEGMENT_H
#define _ASM_X86_SEGMENT_H
#include <linux/const.h>
/* Constructor for a conventional segment GDT (or LDT) entry */
/* This is a macro so it can be used in initializers */
#define GDT_ENTRY(flags, base, limit) \
((((base) & 0xff000000ULL) << (56-24)) | \
(((flags) & 0x0000f0ffULL) << 40) | \
(((limit) & 0x000f0000ULL) << (48-16)) | \
(((base) & 0x00ffffffULL) << 16) | \
(((limit) & 0x0000ffffULL)))
((((base) & _AC(0xff000000,ULL)) << (56-24)) | \
(((flags) & _AC(0x0000f0ff,ULL)) << 40) | \
(((limit) & _AC(0x000f0000,ULL)) << (48-16)) | \
(((base) & _AC(0x00ffffff,ULL)) << 16) | \
(((limit) & _AC(0x0000ffff,ULL))))
/* Simple and small GDT entries for booting only */

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@ -3,25 +3,36 @@
#ifndef __ASSEMBLY__
#ifdef CONFIG_X86_TRAMPOLINE
#include <linux/types.h>
#include <asm/io.h>
/*
* Trampoline 80x86 program as an array.
* Trampoline 80x86 program as an array. These are in the init rodata
* segment, but that's okay, because we only care about the relative
* addresses of the symbols.
*/
extern const unsigned char trampoline_data [];
extern const unsigned char trampoline_end [];
extern unsigned char *trampoline_base;
extern const unsigned char x86_trampoline_start [];
extern const unsigned char x86_trampoline_end [];
extern unsigned char *x86_trampoline_base;
extern unsigned long init_rsp;
extern unsigned long initial_code;
extern unsigned long initial_gs;
#define TRAMPOLINE_SIZE roundup(trampoline_end - trampoline_data, PAGE_SIZE)
extern void __init setup_trampolines(void);
extern unsigned long setup_trampoline(void);
extern void __init reserve_trampoline_memory(void);
#else
static inline void reserve_trampoline_memory(void) {}
#endif /* CONFIG_X86_TRAMPOLINE */
extern const unsigned char trampoline_data[];
extern const unsigned char trampoline_status[];
#define TRAMPOLINE_SYM(x) \
((void *)(x86_trampoline_base + \
((const unsigned char *)(x) - x86_trampoline_start)))
/* Address of the SMP trampoline */
static inline unsigned long trampoline_address(void)
{
return virt_to_phys(TRAMPOLINE_SYM(trampoline_data));
}
#endif /* __ASSEMBLY__ */

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@ -47,7 +47,7 @@ obj-y += tsc.o io_delay.o rtc.o
obj-y += pci-iommu_table.o
obj-y += resource.o
obj-$(CONFIG_X86_TRAMPOLINE) += trampoline.o
obj-y += trampoline.o trampoline_$(BITS).o
obj-y += process.o
obj-y += i387.o xsave.o
obj-y += ptrace.o
@ -59,6 +59,7 @@ obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-y += cpu/
obj-y += acpi/
obj-y += reboot.o
obj-$(CONFIG_X86_32) += reboot_32.o
obj-$(CONFIG_MCA) += mca_32.o
obj-$(CONFIG_X86_MSR) += msr.o
obj-$(CONFIG_X86_CPUID) += cpuid.o
@ -69,7 +70,6 @@ obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_SMP) += smpboot.o
obj-$(CONFIG_SMP) += tsc_sync.o
obj-$(CONFIG_SMP) += setup_percpu.o
obj-$(CONFIG_X86_TRAMPOLINE) += trampoline_$(BITS).o
obj-$(CONFIG_X86_MPPARSE) += mpparse.o
obj-y += apic/
obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o

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@ -6,11 +6,17 @@
#include <asm/page_types.h>
#include <asm/pgtable_types.h>
#include <asm/processor-flags.h>
#include "wakeup.h"
.code16
.section ".header", "a"
.section ".jump", "ax"
.globl _start
_start:
cli
jmp wakeup_code
/* This should match the structure in wakeup.h */
.section ".header", "a"
.globl wakeup_header
wakeup_header:
video_mode: .short 0 /* Video mode number */
@ -30,14 +36,11 @@ wakeup_jmp: .byte 0xea /* ljmpw */
wakeup_jmp_off: .word 3f
wakeup_jmp_seg: .word 0
wakeup_gdt: .quad 0, 0, 0
signature: .long 0x51ee1111
signature: .long WAKEUP_HEADER_SIGNATURE
.text
.globl _start
.code16
wakeup_code:
_start:
cli
cld
/* Apparently some dimwit BIOS programmers don't know how to
@ -77,12 +80,12 @@ _start:
/* Check header signature... */
movl signature, %eax
cmpl $0x51ee1111, %eax
cmpl $WAKEUP_HEADER_SIGNATURE, %eax
jne bogus_real_magic
/* Check we really have everything... */
movl end_signature, %eax
cmpl $0x65a22c82, %eax
cmpl $WAKEUP_END_SIGNATURE, %eax
jne bogus_real_magic
/* Call the C code */
@ -147,3 +150,7 @@ wakeup_heap:
wakeup_stack:
.space 2048
wakeup_stack_end:
.section ".signature","a"
end_signature:
.long WAKEUP_END_SIGNATURE

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@ -35,7 +35,8 @@ struct wakeup_header {
extern struct wakeup_header wakeup_header;
#endif
#define HEADER_OFFSET 0x3f00
#define WAKEUP_SIZE 0x4000
#define WAKEUP_HEADER_OFFSET 8
#define WAKEUP_HEADER_SIGNATURE 0x51ee1111
#define WAKEUP_END_SIGNATURE 0x65a22c82
#endif /* ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H */

View File

@ -13,9 +13,19 @@ ENTRY(_start)
SECTIONS
{
. = 0;
.jump : {
*(.jump)
} = 0x90909090
. = WAKEUP_HEADER_OFFSET;
.header : {
*(.header)
}
. = ALIGN(16);
.text : {
*(.text*)
}
} = 0x90909090
. = ALIGN(16);
.rodata : {
@ -33,11 +43,6 @@ SECTIONS
*(.data*)
}
.signature : {
end_signature = .;
LONG(0x65a22c82)
}
. = ALIGN(16);
.bss : {
__bss_start = .;
@ -45,20 +50,13 @@ SECTIONS
__bss_end = .;
}
. = HEADER_OFFSET;
.header : {
*(.header)
.signature : {
*(.signature)
}
. = ALIGN(16);
_end = .;
/DISCARD/ : {
*(.note*)
}
/*
* The ASSERT() sink to . is intentional, for binutils 2.14 compatibility:
*/
. = ASSERT(_end <= WAKEUP_SIZE, "Wakeup too big!");
}

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@ -18,12 +18,8 @@
#include "realmode/wakeup.h"
#include "sleep.h"
unsigned long acpi_wakeup_address;
unsigned long acpi_realmode_flags;
/* address in low memory of the wakeup routine. */
static unsigned long acpi_realmode;
#if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
static char temp_stack[4096];
#endif
@ -33,22 +29,17 @@ static char temp_stack[4096];
*
* Create an identity mapped page table and copy the wakeup routine to
* low memory.
*
* Note that this is too late to change acpi_wakeup_address.
*/
int acpi_save_state_mem(void)
{
struct wakeup_header *header;
/* address in low memory of the wakeup routine. */
char *acpi_realmode;
if (!acpi_realmode) {
printk(KERN_ERR "Could not allocate memory during boot, "
"S3 disabled\n");
return -ENOMEM;
}
memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE);
acpi_realmode = TRAMPOLINE_SYM(acpi_wakeup_code);
header = (struct wakeup_header *)(acpi_realmode + HEADER_OFFSET);
if (header->signature != 0x51ee1111) {
header = (struct wakeup_header *)(acpi_realmode + WAKEUP_HEADER_OFFSET);
if (header->signature != WAKEUP_HEADER_SIGNATURE) {
printk(KERN_ERR "wakeup header does not match\n");
return -EINVAL;
}
@ -68,9 +59,7 @@ int acpi_save_state_mem(void)
/* GDT[0]: GDT self-pointer */
header->wakeup_gdt[0] =
(u64)(sizeof(header->wakeup_gdt) - 1) +
((u64)(acpi_wakeup_address +
((char *)&header->wakeup_gdt - (char *)acpi_realmode))
<< 16);
((u64)__pa(&header->wakeup_gdt) << 16);
/* GDT[1]: big real mode-like code segment */
header->wakeup_gdt[1] =
GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff);
@ -96,7 +85,7 @@ int acpi_save_state_mem(void)
header->pmode_cr3 = (u32)__pa(&initial_page_table);
saved_magic = 0x12345678;
#else /* CONFIG_64BIT */
header->trampoline_segment = setup_trampoline() >> 4;
header->trampoline_segment = trampoline_address() >> 4;
#ifdef CONFIG_SMP
stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
early_gdt_descr.address =
@ -117,46 +106,6 @@ void acpi_restore_state_mem(void)
{
}
/**
* acpi_reserve_wakeup_memory - do _very_ early ACPI initialisation
*
* We allocate a page from the first 1MB of memory for the wakeup
* routine for when we come back from a sleep state. The
* runtime allocator allows specification of <16MB pages, but not
* <1MB pages.
*/
void __init acpi_reserve_wakeup_memory(void)
{
phys_addr_t mem;
if ((&wakeup_code_end - &wakeup_code_start) > WAKEUP_SIZE) {
printk(KERN_ERR
"ACPI: Wakeup code way too big, S3 disabled.\n");
return;
}
mem = memblock_find_in_range(0, 1<<20, WAKEUP_SIZE, PAGE_SIZE);
if (mem == MEMBLOCK_ERROR) {
printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
return;
}
acpi_realmode = (unsigned long) phys_to_virt(mem);
acpi_wakeup_address = mem;
memblock_x86_reserve_range(mem, mem + WAKEUP_SIZE, "ACPI WAKEUP");
}
int __init acpi_configure_wakeup_memory(void)
{
if (acpi_realmode)
set_memory_x(acpi_realmode, WAKEUP_SIZE >> PAGE_SHIFT);
return 0;
}
arch_initcall(acpi_configure_wakeup_memory);
static int __init acpi_sleep_setup(char *str)
{
while ((str != NULL) && (*str != '\0')) {

View File

@ -4,13 +4,10 @@
#include <asm/trampoline.h>
extern char wakeup_code_start, wakeup_code_end;
extern unsigned long saved_video_mode;
extern long saved_magic;
extern int wakeup_pmode_return;
extern char swsusp_pg_dir[PAGE_SIZE];
extern unsigned long acpi_copy_wakeup_routine(unsigned long);
extern void wakeup_long64(void);

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@ -2,9 +2,11 @@
* Wrapper script for the realmode binary as a transport object
* before copying to low memory.
*/
.section ".rodata","a"
.globl wakeup_code_start, wakeup_code_end
wakeup_code_start:
#include <asm/page_types.h>
.section ".x86_trampoline","a"
.balign PAGE_SIZE
.globl acpi_wakeup_code
acpi_wakeup_code:
.incbin "arch/x86/kernel/acpi/realmode/wakeup.bin"
wakeup_code_end:
.size wakeup_code_start, .-wakeup_code_start
.size acpi_wakeup_code, .-acpi_wakeup_code

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@ -976,20 +976,10 @@ recalc:
static void apm_power_off(void)
{
unsigned char po_bios_call[] = {
0xb8, 0x00, 0x10, /* movw $0x1000,ax */
0x8e, 0xd0, /* movw ax,ss */
0xbc, 0x00, 0xf0, /* movw $0xf000,sp */
0xb8, 0x07, 0x53, /* movw $0x5307,ax */
0xbb, 0x01, 0x00, /* movw $0x0001,bx */
0xb9, 0x03, 0x00, /* movw $0x0003,cx */
0xcd, 0x15 /* int $0x15 */
};
/* Some bioses don't like being called from CPU != 0 */
if (apm_info.realmode_power_off) {
set_cpus_allowed_ptr(current, cpumask_of(0));
machine_real_restart(po_bios_call, sizeof(po_bios_call));
machine_real_restart(MRR_APM);
} else {
(void)set_system_power_state(APM_STATE_OFF);
}

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@ -1414,7 +1414,7 @@ ENTRY(async_page_fault)
pushl_cfi $do_async_page_fault
jmp error_code
CFI_ENDPROC
END(apf_page_fault)
END(async_page_fault)
#endif
/*

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@ -34,15 +34,6 @@ void __init i386_start_kernel(void)
{
memblock_init();
#ifdef CONFIG_X86_TRAMPOLINE
/*
* But first pinch a few for the stack/trampoline stuff
* FIXME: Don't need the extra page at 4K, but need to fix
* trampoline before removing it. (see the GDT stuff)
*/
memblock_x86_reserve_range(PAGE_SIZE, PAGE_SIZE + PAGE_SIZE, "EX TRAMPOLINE");
#endif
memblock_x86_reserve_range(__pa_symbol(&_text), __pa_symbol(&__bss_stop), "TEXT DATA BSS");
#ifdef CONFIG_BLK_DEV_INITRD

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@ -136,10 +136,9 @@ ident_complete:
/* Fixup phys_base */
addq %rbp, phys_base(%rip)
#ifdef CONFIG_X86_TRAMPOLINE
/* Fixup trampoline */
addq %rbp, trampoline_level4_pgt + 0(%rip)
addq %rbp, trampoline_level4_pgt + (511*8)(%rip)
#endif
/* Due to ENTRY(), sometimes the empty space gets filled with
* zeros. Better take a jmp than relying on empty space being

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@ -303,68 +303,16 @@ static int __init reboot_init(void)
}
core_initcall(reboot_init);
/* The following code and data reboots the machine by switching to real
mode and jumping to the BIOS reset entry point, as if the CPU has
really been reset. The previous version asked the keyboard
controller to pulse the CPU reset line, which is more thorough, but
doesn't work with at least one type of 486 motherboard. It is easy
to stop this code working; hence the copious comments. */
static const unsigned long long
real_mode_gdt_entries [3] =
extern const unsigned char machine_real_restart_asm[];
extern const u64 machine_real_restart_gdt[3];
void machine_real_restart(unsigned int type)
{
0x0000000000000000ULL, /* Null descriptor */
0x00009b000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */
0x000093000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */
};
void *restart_va;
unsigned long restart_pa;
void (*restart_lowmem)(unsigned int);
u64 *lowmem_gdt;
static const struct desc_ptr
real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
real_mode_idt = { 0x3ff, 0 };
/* This is 16-bit protected mode code to disable paging and the cache,
switch to real mode and jump to the BIOS reset code.
The instruction that switches to real mode by writing to CR0 must be
followed immediately by a far jump instruction, which set CS to a
valid value for real mode, and flushes the prefetch queue to avoid
running instructions that have already been decoded in protected
mode.
Clears all the flags except ET, especially PG (paging), PE
(protected-mode enable) and TS (task switch for coprocessor state
save). Flushes the TLB after paging has been disabled. Sets CD and
NW, to disable the cache on a 486, and invalidates the cache. This
is more like the state of a 486 after reset. I don't know if
something else should be done for other chips.
More could be done here to set up the registers as if a CPU reset had
occurred; hopefully real BIOSs don't assume much. */
static const unsigned char real_mode_switch [] =
{
0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */
0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */
0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */
0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */
0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */
0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */
0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */
0x74, 0x02, /* jz f */
0x0f, 0x09, /* wbinvd */
0x24, 0x10, /* f: andb $0x10,al */
0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */
};
static const unsigned char jump_to_bios [] =
{
0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */
};
/*
* Switch to real mode and then execute the code
* specified by the code and length parameters.
* We assume that length will aways be less that 100!
*/
void machine_real_restart(const unsigned char *code, int length)
{
local_irq_disable();
/* Write zero to CMOS register number 0x0f, which the BIOS POST
@ -392,41 +340,23 @@ void machine_real_restart(const unsigned char *code, int length)
too. */
*((unsigned short *)0x472) = reboot_mode;
/* For the switch to real mode, copy some code to low memory. It has
to be in the first 64k because it is running in 16-bit mode, and it
has to have the same physical and virtual address, because it turns
off paging. Copy it near the end of the first page, out of the way
of BIOS variables. */
memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100),
real_mode_switch, sizeof (real_mode_switch));
memcpy((void *)(0x1000 - 100), code, length);
/* Patch the GDT in the low memory trampoline */
lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
/* Set up the IDT for real mode. */
load_idt(&real_mode_idt);
restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
restart_pa = virt_to_phys(restart_va);
restart_lowmem = (void (*)(unsigned int))restart_pa;
/* Set up a GDT from which we can load segment descriptors for real
mode. The GDT is not used in real mode; it is just needed here to
prepare the descriptors. */
load_gdt(&real_mode_gdt);
/* GDT[0]: GDT self-pointer */
lowmem_gdt[0] =
(u64)(sizeof(machine_real_restart_gdt) - 1) +
((u64)virt_to_phys(lowmem_gdt) << 16);
/* GDT[1]: 64K real mode code segment */
lowmem_gdt[1] =
GDT_ENTRY(0x009b, restart_pa, 0xffff);
/* Load the data segment registers, and thus the descriptors ready for
real mode. The base address of each segment is 0x100, 16 times the
selector value being loaded here. This is so that the segment
registers don't have to be reloaded after switching to real mode:
the values are consistent for real mode operation already. */
__asm__ __volatile__ ("movl $0x0010,%%eax\n"
"\tmovl %%eax,%%ds\n"
"\tmovl %%eax,%%es\n"
"\tmovl %%eax,%%fs\n"
"\tmovl %%eax,%%gs\n"
"\tmovl %%eax,%%ss" : : : "eax");
/* Jump to the 16-bit code that we copied earlier. It disables paging
and the cache, switches to real mode, and jumps to the BIOS reset
entry point. */
__asm__ __volatile__ ("ljmp $0x0008,%0"
:
: "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100)));
/* Jump to the identity-mapped low memory code */
restart_lowmem(type);
}
#ifdef CONFIG_APM_MODULE
EXPORT_SYMBOL(machine_real_restart);
@ -581,7 +511,7 @@ static void native_machine_emergency_restart(void)
#ifdef CONFIG_X86_32
case BOOT_BIOS:
machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
machine_real_restart(MRR_BIOS);
reboot_type = BOOT_KBD;
break;

135
arch/x86/kernel/reboot_32.S Normal file
View File

@ -0,0 +1,135 @@
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/segment.h>
#include <asm/page_types.h>
/*
* The following code and data reboots the machine by switching to real
* mode and jumping to the BIOS reset entry point, as if the CPU has
* really been reset. The previous version asked the keyboard
* controller to pulse the CPU reset line, which is more thorough, but
* doesn't work with at least one type of 486 motherboard. It is easy
* to stop this code working; hence the copious comments.
*
* This code is called with the restart type (0 = BIOS, 1 = APM) in %eax.
*/
.section ".x86_trampoline","a"
.balign 16
.code32
ENTRY(machine_real_restart_asm)
r_base = .
/* Get our own relocated address */
call 1f
1: popl %ebx
subl $1b, %ebx
/* Compute the equivalent real-mode segment */
movl %ebx, %ecx
shrl $4, %ecx
/* Patch post-real-mode segment jump */
movw dispatch_table(%ebx,%eax,2),%ax
movw %ax, 101f(%ebx)
movw %cx, 102f(%ebx)
/* Set up the IDT for real mode. */
lidtl machine_real_restart_idt(%ebx)
/*
* Set up a GDT from which we can load segment descriptors for real
* mode. The GDT is not used in real mode; it is just needed here to
* prepare the descriptors.
*/
lgdtl machine_real_restart_gdt(%ebx)
/*
* Load the data segment registers with 16-bit compatible values
*/
movl $16, %ecx
movl %ecx, %ds
movl %ecx, %es
movl %ecx, %fs
movl %ecx, %gs
movl %ecx, %ss
ljmpl $8, $1f - r_base
/*
* This is 16-bit protected mode code to disable paging and the cache,
* switch to real mode and jump to the BIOS reset code.
*
* The instruction that switches to real mode by writing to CR0 must be
* followed immediately by a far jump instruction, which set CS to a
* valid value for real mode, and flushes the prefetch queue to avoid
* running instructions that have already been decoded in protected
* mode.
*
* Clears all the flags except ET, especially PG (paging), PE
* (protected-mode enable) and TS (task switch for coprocessor state
* save). Flushes the TLB after paging has been disabled. Sets CD and
* NW, to disable the cache on a 486, and invalidates the cache. This
* is more like the state of a 486 after reset. I don't know if
* something else should be done for other chips.
*
* More could be done here to set up the registers as if a CPU reset had
* occurred; hopefully real BIOSs don't assume much. This is not the
* actual BIOS entry point, anyway (that is at 0xfffffff0).
*
* Most of this work is probably excessive, but it is what is tested.
*/
.code16
1:
xorl %ecx, %ecx
movl %cr0, %eax
andl $0x00000011, %eax
orl $0x60000000, %eax
movl %eax, %cr0
movl %ecx, %cr3
movl %cr0, %edx
andl $0x60000000, %edx /* If no cache bits -> no wbinvd */
jz 2f
wbinvd
2:
andb $0x10, %al
movl %eax, %cr0
.byte 0xea /* ljmpw */
101: .word 0 /* Offset */
102: .word 0 /* Segment */
bios:
ljmpw $0xf000, $0xfff0
apm:
movw $0x1000, %ax
movw %ax, %ss
movw $0xf000, %sp
movw $0x5307, %ax
movw $0x0001, %bx
movw $0x0003, %cx
int $0x15
END(machine_real_restart_asm)
.balign 16
/* These must match <asm/reboot.h */
dispatch_table:
.word bios - r_base
.word apm - r_base
END(dispatch_table)
.balign 16
machine_real_restart_idt:
.word 0xffff /* Length - real mode default value */
.long 0 /* Base - real mode default value */
END(machine_real_restart_idt)
.balign 16
ENTRY(machine_real_restart_gdt)
.quad 0 /* Self-pointer, filled in by PM code */
.quad 0 /* 16-bit code segment, filled in by PM code */
/*
* 16-bit data segment with the selector value 16 = 0x10 and
* base value 0x100; since this is consistent with real mode
* semantics we don't have to reload the segments once CR0.PE = 0.
*/
.quad GDT_ENTRY(0x0093, 0x100, 0xffff)
END(machine_real_restart_gdt)

View File

@ -963,15 +963,8 @@ void __init setup_arch(char **cmdline_p)
printk(KERN_DEBUG "initial memory mapped : 0 - %08lx\n",
max_pfn_mapped<<PAGE_SHIFT);
reserve_trampoline_memory();
setup_trampolines();
#ifdef CONFIG_ACPI_SLEEP
/*
* Reserve low memory region for sleep support.
* even before init_memory_mapping
*/
acpi_reserve_wakeup_memory();
#endif
init_gbpages();
/* max_pfn_mapped is updated here */

View File

@ -711,7 +711,7 @@ do_rest:
stack_start = c_idle.idle->thread.sp;
/* start_ip had better be page-aligned! */
start_ip = setup_trampoline();
start_ip = trampoline_address();
/* So we see what's up */
announce_cpu(cpu, apicid);
@ -721,6 +721,8 @@ do_rest:
* the targeted processor.
*/
printk(KERN_DEBUG "smpboot cpu %d: start_ip = %lx\n", cpu, start_ip);
atomic_set(&init_deasserted, 0);
if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
@ -774,8 +776,8 @@ do_rest:
pr_debug("CPU%d: has booted.\n", cpu);
else {
boot_error = 1;
if (*((volatile unsigned char *)trampoline_base)
== 0xA5)
if (*(volatile u32 *)TRAMPOLINE_SYM(trampoline_status)
== 0xA5A5A5A5)
/* trampoline started but...? */
pr_err("CPU%d: Stuck ??\n", cpu);
else
@ -801,7 +803,7 @@ do_rest:
}
/* mark "stuck" area as not stuck */
*((volatile unsigned long *)trampoline_base) = 0;
*(volatile u32 *)TRAMPOLINE_SYM(trampoline_status) = 0;
if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
/*

View File

@ -2,39 +2,41 @@
#include <linux/memblock.h>
#include <asm/trampoline.h>
#include <asm/cacheflush.h>
#include <asm/pgtable.h>
#if defined(CONFIG_X86_64) && defined(CONFIG_ACPI_SLEEP)
#define __trampinit
#define __trampinitdata
#else
#define __trampinit __cpuinit
#define __trampinitdata __cpuinitdata
#endif
unsigned char *x86_trampoline_base;
/* ready for x86_64 and x86 */
unsigned char *__trampinitdata trampoline_base;
void __init reserve_trampoline_memory(void)
void __init setup_trampolines(void)
{
phys_addr_t mem;
size_t size = PAGE_ALIGN(x86_trampoline_end - x86_trampoline_start);
/* Has to be in very low memory so we can execute real-mode AP code. */
mem = memblock_find_in_range(0, 1<<20, TRAMPOLINE_SIZE, PAGE_SIZE);
mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE);
if (mem == MEMBLOCK_ERROR)
panic("Cannot allocate trampoline\n");
trampoline_base = __va(mem);
memblock_x86_reserve_range(mem, mem + TRAMPOLINE_SIZE, "TRAMPOLINE");
x86_trampoline_base = __va(mem);
memblock_x86_reserve_range(mem, mem + size, "TRAMPOLINE");
printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n",
x86_trampoline_base, (unsigned long long)mem, size);
memcpy(x86_trampoline_base, x86_trampoline_start, size);
}
/*
* Currently trivial. Write the real->protected mode
* bootstrap into the page concerned. The caller
* has made sure it's suitably aligned.
* setup_trampolines() gets called very early, to guarantee the
* availability of low memory. This is before the proper kernel page
* tables are set up, so we cannot set page permissions in that
* function. Thus, we use an arch_initcall instead.
*/
unsigned long __trampinit setup_trampoline(void)
static int __init configure_trampolines(void)
{
memcpy(trampoline_base, trampoline_data, TRAMPOLINE_SIZE);
return virt_to_phys(trampoline_base);
size_t size = PAGE_ALIGN(x86_trampoline_end - x86_trampoline_start);
set_memory_x((unsigned long)x86_trampoline_base, size >> PAGE_SHIFT);
return 0;
}
arch_initcall(configure_trampolines);

View File

@ -32,9 +32,11 @@
#include <asm/segment.h>
#include <asm/page_types.h>
/* We can free up trampoline after bootup if cpu hotplug is not supported. */
__CPUINITRODATA
.code16
#ifdef CONFIG_SMP
.section ".x86_trampoline","a"
.balign PAGE_SIZE
.code16
ENTRY(trampoline_data)
r_base = .
@ -44,7 +46,7 @@ r_base = .
cli # We should be safe anyway
movl $0xA5A5A5A5, trampoline_data - r_base
movl $0xA5A5A5A5, trampoline_status - r_base
# write marker for master knows we're running
/* GDT tables in non default location kernel can be beyond 16MB and
@ -72,5 +74,10 @@ boot_idt_descr:
.word 0 # idt limit = 0
.long 0 # idt base = 0L
ENTRY(trampoline_status)
.long 0
.globl trampoline_end
trampoline_end:
#endif /* CONFIG_SMP */

View File

@ -32,13 +32,9 @@
#include <asm/segment.h>
#include <asm/processor-flags.h>
#ifdef CONFIG_ACPI_SLEEP
.section .rodata, "a", @progbits
#else
/* We can free up the trampoline after bootup if cpu hotplug is not supported. */
__CPUINITRODATA
#endif
.code16
.section ".x86_trampoline","a"
.balign PAGE_SIZE
.code16
ENTRY(trampoline_data)
r_base = .
@ -50,7 +46,7 @@ r_base = .
mov %ax, %ss
movl $0xA5A5A5A5, trampoline_data - r_base
movl $0xA5A5A5A5, trampoline_status - r_base
# write marker for master knows we're running
# Setup stack
@ -64,10 +60,13 @@ r_base = .
movzx %ax, %esi # Find the 32bit trampoline location
shll $4, %esi
# Fixup the vectors
addl %esi, startup_32_vector - r_base
addl %esi, startup_64_vector - r_base
addl %esi, tgdt + 2 - r_base # Fixup the gdt pointer
# Fixup the absolute vectors
leal (startup_32 - r_base)(%esi), %eax
movl %eax, startup_32_vector - r_base
leal (startup_64 - r_base)(%esi), %eax
movl %eax, startup_64_vector - r_base
leal (tgdt - r_base)(%esi), %eax
movl %eax, (tgdt + 2 - r_base)
/*
* GDT tables in non default location kernel can be beyond 16MB and
@ -129,6 +128,7 @@ no_longmode:
jmp no_longmode
#include "verify_cpu.S"
.balign 4
# Careful these need to be in the same 64K segment as the above;
tidt:
.word 0 # idt limit = 0
@ -156,6 +156,10 @@ startup_64_vector:
.long startup_64 - r_base
.word __KERNEL_CS, 0
.balign 4
ENTRY(trampoline_status)
.long 0
trampoline_stack:
.org 0x1000
trampoline_stack_end:

View File

@ -241,6 +241,18 @@ SECTIONS
INIT_DATA_SECTION(16)
/*
* Code and data for a variety of lowlevel trampolines, to be
* copied into base memory (< 1 MiB) during initialization.
* Since it is copied early, the main copy can be discarded
* afterwards.
*/
.x86_trampoline : AT(ADDR(.x86_trampoline) - LOAD_OFFSET) {
x86_trampoline_start = .;
*(.x86_trampoline)
x86_trampoline_end = .;
}
.x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
__x86_cpu_dev_start = .;
*(.x86_cpu_dev.init)
@ -292,6 +304,7 @@ SECTIONS
*(.iommu_table)
__iommu_table_end = .;
}
. = ALIGN(8);
/*
* .exit.text is discard at runtime, not link time, to deal with

View File

@ -16,6 +16,7 @@
#include <linux/device.h>
#include <linux/suspend.h>
#include <linux/reboot.h>
#include <linux/acpi.h>
#include <asm/io.h>