diff options
Diffstat (limited to 'payloads/libpayload/arch/x86/exception.c')
| -rw-r--r-- | payloads/libpayload/arch/x86/exception.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/payloads/libpayload/arch/x86/exception.c b/payloads/libpayload/arch/x86/exception.c new file mode 100644 index 0000000000..a9a65ca5a2 --- /dev/null +++ b/payloads/libpayload/arch/x86/exception.c @@ -0,0 +1,199 @@ +/* + * 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. + */ + +#include <exception.h> +#include <libpayload.h> +#include <stdint.h> + +uint8_t exception_stack[0x1000] __attribute__((aligned(8))); +extern void *exception_stack_end; + +struct exception_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; + u32 error_code; + u32 vector; +} __attribute__((packed)); + +struct exception_info +{ + const char *name; + void (*error_code_printer)(u32 code); +}; + +static void print_segment_error_code(u32 code) +{ + printf("%#x - descriptor %#x in the ", code, (code >> 3) & 0x1f); + if (code & (0x1 << 1)) { + printf("IDT"); + } else { + if (code & 0x04) + printf("LDT"); + else + printf("GDT"); + } + if (code & (0x1 << 0)) + printf(", external to the CPU"); + else + printf(", internal to the CPU"); +} + +static void print_page_fault_error_code(u32 code) +{ + printf("%#x -", code); + if (code & (0x1 << 0)) + printf(" page protection"); + else + printf(" page not present"); + if (code & (0x1 << 1)) + printf(", write"); + else + printf(", read"); + if (code & (0x1 << 2)) + printf(", user"); + else + printf(", supervisor"); + if (code & (0x1 << 3)) + printf(", reserved bits set"); + if (code & (0x1 << 4)) + printf(", instruction fetch"); +} + +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", + .error_code_printer = &print_raw_error_code }, + [10] = { .name = "invalid tss", + .error_code_printer = &print_segment_error_code }, + [11] = { .name = "segment not present", + .error_code_printer = &print_segment_error_code }, + [12] = { .name = "stack", + .error_code_printer = &print_segment_error_code }, + [13] = { .name = "general protection", + .error_code_printer = &print_segment_error_code }, + [14] = { .name = "page fault", + .error_code_printer = &print_page_fault_error_code }, + [16] = { .name = "x87 floating point" }, + [17] = { .name = "alignment check", + .error_code_printer = &print_raw_error_code }, + [18] = { .name = "machine check" }, + [19] = { .name = "SIMD floating point" }, + [30] = { .name = "security", + .error_code_printer = &print_raw_error_code }, +}; + +static void dump_stack(uintptr_t addr, size_t bytes) +{ + int i, j; + const int line = 8; + uint32_t *ptr = (uint32_t *)(addr & ~(line * sizeof(*ptr) - 1)); + + printf("Dumping stack:\n"); + for (i = bytes / sizeof(*ptr); i >= 0; i -= line) { + printf("%p: ", ptr + i); + for (j = i; j < i + line; j++) + printf("%08x ", *(ptr + j)); + printf("\n"); + } +} + +void exception_handler(void); +void exception_handler(void) +{ + 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 + printf("Unrecognized exception %d\n", state->vector); + if (info->error_code_printer) { + printf("Error code: "); + 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(); +} + +void exception_init_asm(void); +void exception_init(void) +{ + exception_stack_end = exception_stack + sizeof(exception_stack); + exception_init_asm(); +} |