libpayload: Make it possible to install callbacks for particular exceptions.

To support a GDB stub, it will be necessary to trap various exceptions which
will be used to implement breakpoints, single stepping, etc.

BUG=None
TEST=Built and booted on Link with hooks installed and saw that they
triggered when exceptions occurred. Built and booted on nyan.
BRANCH=None

Original-Change-Id: Iab659365864a3055159a50b8f6e5c44290d3ba2b
Original-Signed-off-by: Gabe Black <gabeblack@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/179602
Original-Reviewed-by: Gabe Black <gabeblack@chromium.org>
Original-Tested-by: Gabe Black <gabeblack@chromium.org>
Original-Commit-Queue: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit 8db0897b1ddad600e247cb4df147c757a8187626)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I5e7f724b99988cd259909dd3bd01166fa52317ec
Reviewed-on: http://review.coreboot.org/7656
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
This commit is contained in:
Gabe Black 2013-12-11 00:23:15 -08:00 committed by Marc Jones
parent c09cf0b7e1
commit 20cdb2439f
8 changed files with 237 additions and 162 deletions

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@ -29,19 +29,27 @@
#include <arch/cache.h>
#include <arch/exception.h>
#include <exception.h>
#include <libpayload.h>
#include <stdint.h>
uint8_t exception_stack[0x100] __attribute__((aligned(8)));
uint8_t exception_stack[0x1000] __attribute__((aligned(8)));
extern void *exception_stack_end;
void exception_undefined_instruction(uint32_t *);
void exception_software_interrupt(uint32_t *);
void exception_prefetch_abort(uint32_t *);
void exception_data_abort(uint32_t *);
void exception_not_used(uint32_t *);
void exception_irq(uint32_t *);
void exception_fiq(uint32_t *);
struct exception_handler_info
{
const char *name;
exception_hook hook;
};
static struct exception_handler_info exceptions[EXC_COUNT] = {
[EXC_UNDEF] = { "_undefined_instruction" },
[EXC_SWI] = { "_software_interrupt" },
[EXC_PABORT] = { "_prefetch_abort" },
[EXC_DABORT] = { "_data_abort" },
[EXC_IRQ] = { "_irq" },
[EXC_FIQ] = { "_fiq" },
};
static void dump_stack(uintptr_t addr, size_t bytes)
{
@ -77,59 +85,25 @@ static void print_regs(uint32_t *regs)
}
}
void exception_undefined_instruction(uint32_t *regs)
void exception_dispatch(struct exception_state *state, int idx);
void exception_dispatch(struct exception_state *state, int idx)
{
printf("exception _undefined_instruction\n");
print_regs(regs);
dump_stack(regs[13], 512);
halt();
if (idx >= EXC_COUNT) {
printf("Bad exception index %d.\n", idx);
} else {
struct exception_handler_info *info = &exceptions[idx];
if (info->hook) {
info->hook(idx, state);
return;
}
void exception_software_interrupt(uint32_t *regs)
{
printf("exception _software_interrupt\n");
print_regs(regs);
dump_stack(regs[13], 512);
halt();
if (info->name)
printf("exception %s\n", info->name);
else
printf("exception _not_used.\n");
}
void exception_prefetch_abort(uint32_t *regs)
{
printf("exception _prefetch_abort\n");
print_regs(regs);
dump_stack(regs[13], 512);
halt();
}
void exception_data_abort(uint32_t *regs)
{
printf("exception _data_abort\n");
print_regs(regs);
dump_stack(regs[13], 512);
halt();
}
void exception_not_used(uint32_t *regs)
{
printf("exception _not_used\n");
print_regs(regs);
dump_stack(regs[13], 512);
halt();
}
void exception_irq(uint32_t *regs)
{
printf("exception _irq\n");
print_regs(regs);
dump_stack(regs[13], 512);
halt();
}
void exception_fiq(uint32_t *regs)
{
printf("exception _fiq\n");
print_regs(regs);
dump_stack(regs[13], 512);
print_regs(state->regs);
dump_stack(state->regs[13], 512);
halt();
}
@ -146,3 +120,9 @@ void exception_init(void)
set_vbar((uintptr_t)exception_table);
exception_stack_end = exception_stack + sizeof(exception_stack);
}
void exception_install_hook(int type, exception_hook hook)
{
die_if(type >= EXC_COUNT, "Out of bounds exception index %d.\n", type);
exceptions[type].hook = hook;
}

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@ -43,59 +43,51 @@ exception_table:
b 8f
1:
ldr sp, _not_used
mov sp, $0
b exception_common
2:
ldr sp, _undefined_instruction
mov sp, $1
b exception_common
3:
ldr sp, _software_interrupt
mov sp, $2
b exception_common
4:
ldr sp, _prefetch_abort
mov sp, $3
b exception_common
5:
ldr sp, _data_abort
mov sp, $4
b exception_common
6:
ldr sp, _not_used
mov sp, $5
b exception_common
7:
ldr sp, _irq
mov sp, $6
b exception_common
8:
ldr sp, _fiq
mov sp, $7
b exception_common
exception_common:
str sp, exception_handler
str sp, exception_idx
ldr sp, exception_stack_end
push { lr }
stmfd sp, { sp, lr }^
sub sp, sp, $8
push { r0 - r12 }
mov r0, sp
mov lr, pc
ldr pc, exception_handler
ldr r1, exception_idx
blx exception_dispatch
pop { r0 - r12 }
add sp, sp, $8
ldmfd sp!, { pc }^
.align 2
_undefined_instruction: .word exception_undefined_instruction
_software_interrupt: .word exception_software_interrupt
_prefetch_abort: .word exception_prefetch_abort
_data_abort: .word exception_data_abort
_not_used: .word exception_not_used
_irq: .word exception_irq
_fiq: .word exception_fiq
.global exception_stack_end
exception_stack_end:
.word 0
exception_handler:
exception_idx:
.word 0
.thumb

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@ -27,7 +27,7 @@
* SUCH DAMAGE.
*/
#include <arch/exception.h>
#include <exception.h>
#include <libpayload.h>
unsigned int main_argc; /**< The argc value to pass to main() */

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@ -27,39 +27,27 @@
* SUCH DAMAGE.
*/
#include <arch/exception.h>
#include <exception.h>
#include <libpayload.h>
#include <stdint.h>
uint8_t exception_stack[0x1000] __attribute__((aligned(8)));
extern void *exception_stack_end;
extern struct exception_handler_state *exception_handler_state_handoff;
struct exception_state
struct exception_handler_state
{
u32 eax;
u32 ecx;
u32 edx;
u32 ebx;
u32 esp;
u32 ebp;
u32 esi;
u32 edi;
u32 eip;
u32 eflags;
u32 cs;
u32 ss;
u32 ds;
u32 es;
u32 fs;
u32 gs;
struct exception_state regs;
u32 error_code;
u32 vector;
} __attribute__((packed));
struct exception_info
struct exception_handler_info
{
const char *name;
void (*error_code_printer)(u32 code);
exception_hook hook;
};
static void print_segment_error_code(u32 code)
@ -105,33 +93,33 @@ static void print_raw_error_code(u32 code)
printf("%#x", code);
}
static struct exception_info exceptions[] = {
[0] = { .name = "divide by zero" },
[1] = { .name = "debug" },
[2] = { .name = "non-maskable-interrupt" },
[3] = { .name = "breakpoint" },
[4] = { .name = "overflow" },
[5] = { .name = "bound range" },
[6] = { .name = "invalid opcode" },
[7] = { .name = "device not available" },
[8] = { .name = "double fault",
static struct exception_handler_info exceptions[EXC_COUNT] = {
[EXC_DE] = { .name = "divide by zero" },
[EXC_DB] = { .name = "debug" },
[EXC_NMI] = { .name = "non-maskable-interrupt" },
[EXC_BP] = { .name = "breakpoint" },
[EXC_OF] = { .name = "overflow" },
[EXC_BR] = { .name = "bound range" },
[EXC_UD] = { .name = "invalid opcode" },
[EXC_NM] = { .name = "device not available" },
[EXC_DF] = { .name = "double fault",
.error_code_printer = &print_raw_error_code },
[10] = { .name = "invalid tss",
[EXC_TS] = { .name = "invalid tss",
.error_code_printer = &print_segment_error_code },
[11] = { .name = "segment not present",
[EXC_NP] = { .name = "segment not present",
.error_code_printer = &print_segment_error_code },
[12] = { .name = "stack",
[EXC_SS] = { .name = "stack",
.error_code_printer = &print_segment_error_code },
[13] = { .name = "general protection",
[EXC_GP] = { .name = "general protection",
.error_code_printer = &print_segment_error_code },
[14] = { .name = "page fault",
[EXC_PF] = { .name = "page fault",
.error_code_printer = &print_page_fault_error_code },
[16] = { .name = "x87 floating point" },
[17] = { .name = "alignment check",
[EXC_MF] = { .name = "x87 floating point" },
[EXC_AC] = { .name = "alignment check",
.error_code_printer = &print_raw_error_code },
[18] = { .name = "machine check" },
[19] = { .name = "SIMD floating point" },
[30] = { .name = "security",
[EXC_MC] = { .name = "machine check" },
[EXC_XF] = { .name = "SIMD floating point" },
[EXC_SX] = { .name = "security",
.error_code_printer = &print_raw_error_code },
};
@ -150,16 +138,9 @@ static void dump_stack(uintptr_t addr, size_t bytes)
}
}
void exception_handler(void);
void exception_handler(void)
static void dump_exception_state(struct exception_handler_state *state,
struct exception_handler_info *info)
{
struct exception_state *state =
(void *)((u8 *)exception_stack_end - sizeof(*state));
struct exception_info *info = NULL;
if (state->vector < ARRAY_SIZE(exceptions))
info = &exceptions[state->vector];
if (info)
printf("Exception %d (%s)\n", state->vector, info->name);
else
@ -169,31 +150,50 @@ void exception_handler(void)
info->error_code_printer(state->error_code);
printf("\n");
}
printf("EIP: 0x%08x\n", state->eip);
printf("CS: 0x%04x\n", state->cs);
printf("EFLAGS: 0x%08x\n", state->eflags);
printf("EAX: 0x%08x\n", state->eax);
printf("ECX: 0x%08x\n", state->ecx);
printf("EDX: 0x%08x\n", state->edx);
printf("EBX: 0x%08x\n", state->ebx);
printf("ESP: 0x%08x\n", state->esp);
printf("EBP: 0x%08x\n", state->ebp);
printf("ESI: 0x%08x\n", state->esi);
printf("EDI: 0x%08x\n", state->edi);
printf("DS: 0x%04x\n", state->ds);
printf("ES: 0x%04x\n", state->es);
printf("SS: 0x%04x\n", state->ss);
printf("FS: 0x%04x\n", state->fs);
printf("GS: 0x%04x\n", state->gs);
dump_stack(state->esp, 512);
halt();
printf("EIP: 0x%08x\n", state->regs.eip);
printf("CS: 0x%04x\n", state->regs.cs);
printf("EFLAGS: 0x%08x\n", state->regs.eflags);
printf("EAX: 0x%08x\n", state->regs.eax);
printf("ECX: 0x%08x\n", state->regs.ecx);
printf("EDX: 0x%08x\n", state->regs.edx);
printf("EBX: 0x%08x\n", state->regs.ebx);
printf("ESP: 0x%08x\n", state->regs.esp);
printf("EBP: 0x%08x\n", state->regs.ebp);
printf("ESI: 0x%08x\n", state->regs.esi);
printf("EDI: 0x%08x\n", state->regs.edi);
printf("DS: 0x%04x\n", state->regs.ds);
printf("ES: 0x%04x\n", state->regs.es);
printf("SS: 0x%04x\n", state->regs.ss);
printf("FS: 0x%04x\n", state->regs.fs);
printf("GS: 0x%04x\n", state->regs.gs);
}
void exception_dispatch(void)
{
struct exception_handler_state *state =
exception_handler_state_handoff;
struct exception_handler_info *info = NULL;
if (state->vector < EXC_COUNT)
info = &exceptions[state->vector];
if (info && info->hook) {
info->hook(state->vector, &state->regs);
} else {
dump_exception_state(state, info);
dump_stack(state->regs.esp, 512);
halt();
}
}
void exception_init_asm(void);
void exception_init(void)
{
exception_stack_end = exception_stack + sizeof(exception_stack);
exception_init_asm();
}
void exception_install_hook(int type, exception_hook hook)
{
die_if(type >= EXC_COUNT, "Out of bound exception type %d.\n", type);
exceptions[type].hook = hook;
}

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@ -31,6 +31,9 @@
.global exception_stack_end
exception_stack_end:
.long 0
.global exception_handler_state_handoff
exception_handler_state_handoff:
.long 0
/* Some temporary variables which are used while saving exception state. */
vector:
@ -134,11 +137,13 @@ exception_common:
pushl old_eax
/*
* Call the C exception handler. It will find the exception state on
* the exception stack. Not passing parameters means we don't have to
* worry about what ABI is being used.
* Call the C exception handler. It will find the exception state
* using the exception_handler_state_handoff global pointer. Not
* passing parameters means we don't have to worry about what ABI
* is being used.
*/
call exception_handler
mov %esp, exception_handler_state_handoff
call exception_dispatch
/*
* Restore state from the exception state structure, including any

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@ -30,9 +30,23 @@
#ifndef _ARCH_EXCEPTION_H
#define _ARCH_EXCEPTION_H
#include <exception.h>
#include <stdint.h>
void set_vbar(uint32_t vbar);
struct exception_state
{
uint32_t regs[16];
} __attribute__((packed));
enum {
EXC_UNDEF = 1,
EXC_SWI = 2,
EXC_PABORT = 3,
EXC_DABORT = 4,
EXC_IRQ = 6,
EXC_FIQ = 7,
EXC_COUNT
};
#endif

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@ -30,8 +30,11 @@
#ifndef _EXCEPTION_H
#define _EXCEPTION_H
#include <stdint.h>
#include <arch/exception.h>
typedef void (*exception_hook)(int type, struct exception_state *state);
void exception_init(void);
void exception_install_hook(int type, exception_hook hook);
#endif

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@ -0,0 +1,81 @@
/*
* This file is part of the libpayload project.
*
* Copyright 2013 Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef _ARCH_EXCEPTION_H
#define _ARCH_EXCEPTION_H
#include <stdint.h>
void exception_dispatch(void);
void exception_init_asm(void);
struct exception_state
{
uint32_t eax;
uint32_t ecx;
uint32_t edx;
uint32_t ebx;
uint32_t esp;
uint32_t ebp;
uint32_t esi;
uint32_t edi;
uint32_t eip;
uint32_t eflags;
uint32_t cs;
uint32_t ss;
uint32_t ds;
uint32_t es;
uint32_t fs;
uint32_t gs;
} __attribute__((packed));
enum {
EXC_DE = 0, /* Divide by zero */
EXC_DB = 1, /* Debug */
EXC_NMI = 2, /* Non maskable interrupt */
EXC_BP = 3, /* Breakpoint */
EXC_OF = 4, /* Overflow */
EXC_BR = 5, /* Bound range */
EXC_UD = 6, /* Invalid opcode */
EXC_NM = 7, /* Device not available */
EXC_DF = 8, /* Double fault */
EXC_TS = 10, /* Invalid TSS */
EXC_NP = 11, /* Segment not present */
EXC_SS = 12, /* Stack */
EXC_GP = 13, /* General protection */
EXC_PF = 14, /* Page fault */
EXC_MF = 16, /* x87 floating point */
EXC_AC = 17, /* Alignment check */
EXC_MC = 18, /* Machine check */
EXC_XF = 19, /* SIMD floating point */
EXC_SX = 30, /* Security */
EXC_COUNT
};
#endif