/* * 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 <arch/exception.h> #include <exception.h> #include <libpayload.h> #include <stdint.h> u32 exception_stack[0x400] __attribute__((aligned(8))); static exception_hook hook; static const char *names[EXC_COUNT] = { [EXC_DE] = "Divide by Zero", [EXC_DB] = "Debug", [EXC_NMI] = "Non-Maskable-Interrupt", [EXC_BP] = "Breakpoint", [EXC_OF] = "Overflow", [EXC_BR] = "Bound Range", [EXC_UD] = "Invalid Opcode", [EXC_NM] = "Device Not Available", [EXC_DF] = "Double Fault", [EXC_TS] = "Invalid TSS", [EXC_NP] = "Segment Not Present", [EXC_SS] = "Stack Fault", [EXC_GP] = "General Protection Fault", [EXC_PF] = "Page Fault", [EXC_MF] = "x87 Floating Point", [EXC_AC] = "Alignment Check", [EXC_MC] = "Machine Check", [EXC_XF] = "SIMD Floating Point", [EXC_SX] = "Security", }; static void print_segment_error_code(u32 code) { printf("%#x - descriptor %#x in the ", code, (code >> 3) & 0x1FFF); 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 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"); } } static void dump_exception_state(void) { printf("%s Exception\n", names[exception_state->vector]); printf("Error code: "); switch (exception_state->vector) { case EXC_PF: print_page_fault_error_code(exception_state->error_code); break; case EXC_TS: case EXC_NP: case EXC_SS: case EXC_GP: print_segment_error_code(exception_state->error_code); break; case EXC_DF: case EXC_AC: case EXC_SX: print_raw_error_code(exception_state->error_code); break; default: printf("n/a"); break; } printf("\n"); printf("EIP: 0x%08x\n", exception_state->regs.eip); printf("CS: 0x%04x\n", exception_state->regs.cs); printf("EFLAGS: 0x%08x\n", exception_state->regs.eflags); printf("EAX: 0x%08x\n", exception_state->regs.eax); printf("ECX: 0x%08x\n", exception_state->regs.ecx); printf("EDX: 0x%08x\n", exception_state->regs.edx); printf("EBX: 0x%08x\n", exception_state->regs.ebx); printf("ESP: 0x%08x\n", exception_state->regs.esp); printf("EBP: 0x%08x\n", exception_state->regs.ebp); printf("ESI: 0x%08x\n", exception_state->regs.esi); printf("EDI: 0x%08x\n", exception_state->regs.edi); printf("DS: 0x%04x\n", exception_state->regs.ds); printf("ES: 0x%04x\n", exception_state->regs.es); printf("SS: 0x%04x\n", exception_state->regs.ss); printf("FS: 0x%04x\n", exception_state->regs.fs); printf("GS: 0x%04x\n", exception_state->regs.gs); } void exception_dispatch(void) { u32 vec = exception_state->vector; die_if(vec >= EXC_COUNT || !names[vec], "Bad exception vector %u", vec); if (hook && hook(vec)) return; dump_exception_state(); dump_stack(exception_state->regs.esp, 512); halt(); } void exception_init(void) { exception_stack_end = exception_stack + ARRAY_SIZE(exception_stack); exception_init_asm(); } void exception_install_hook(exception_hook h) { die_if(hook, "Implement support for a list of hooks if you need it."); hook = h; }