| /* |
| * Copyright 2014 Google Inc. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation; either version 2 of |
| * the License, or (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but without any warranty; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #include <exception.h> |
| #include <gdb.h> |
| #include <libpayload.h> |
| |
| static const u8 type_to_signal[] = { |
| [EXC_DE] = GDB_SIGFPE, |
| [EXC_DB] = GDB_SIGTRAP, |
| [EXC_NMI] = GDB_SIGKILL, |
| [EXC_BP] = GDB_SIGTRAP, |
| [EXC_OF] = GDB_SIGFPE, |
| [EXC_BR] = GDB_SIGSEGV, |
| [EXC_UD] = GDB_SIGILL, |
| [EXC_NM] = GDB_SIGEMT, |
| [EXC_DF] = GDB_SIGKILL, |
| [EXC_TS] = GDB_SIGSEGV, |
| [EXC_NP] = GDB_SIGSEGV, |
| [EXC_SS] = GDB_SIGBUS, |
| [EXC_GP] = GDB_SIGSEGV, |
| [EXC_PF] = GDB_SIGSEGV, |
| [EXC_MF] = GDB_SIGEMT, |
| [EXC_AC] = GDB_SIGBUS, |
| [EXC_MC] = GDB_SIGKILL, |
| [EXC_XF] = GDB_SIGFPE, |
| [EXC_SX] = GDB_SIGFPE, |
| }; |
| |
| static void gdb_exception_hook(u8 vector) |
| { |
| gdb_command_loop(type_to_signal[vector]); |
| } |
| |
| void gdb_arch_init(void) |
| { |
| for (int vector = 0; vector < ARRAY_SIZE(type_to_signal); ++vector) { |
| if (type_to_signal[vector]) |
| set_interrupt_handler(vector, &gdb_exception_hook); |
| } |
| } |
| |
| void gdb_arch_enter(void) |
| { |
| u32 *esp; |
| |
| asm volatile ("mov %%esp, %0" : "=r"(esp) ); |
| |
| /* Avoid reentrant exceptions, just call the hook if in one already. */ |
| if (esp >= exception_stack && esp <= exception_stack_end) |
| gdb_exception_hook(EXC_BP); |
| else |
| asm volatile ("int3"); |
| } |
| |
| int gdb_arch_set_single_step(int on) |
| { |
| const u32 tf_bit = 1 << 8; |
| |
| if (on) |
| exception_state->regs.eflags |= tf_bit; |
| else |
| exception_state->regs.eflags &= ~tf_bit; |
| |
| return 0; |
| } |
| |
| void gdb_arch_encode_regs(struct gdb_message *message) |
| { |
| gdb_message_encode_bytes(message, &exception_state->regs, |
| sizeof(exception_state->regs)); |
| } |
| |
| void gdb_arch_decode_regs(int offset, struct gdb_message *message) |
| { |
| gdb_message_decode_bytes(message, offset, &exception_state->regs, |
| sizeof(exception_state->regs)); |
| } |