diff options
Diffstat (limited to 'tools/objtool/arch/x86/decode.c')
| -rw-r--r-- | tools/objtool/arch/x86/decode.c | 111 |
1 files changed, 94 insertions, 17 deletions
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index 0ad5cc70ecbe..f4af82508228 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -16,14 +16,22 @@ #include <asm/orc_types.h> #include <objtool/check.h> +#include <objtool/disas.h> #include <objtool/elf.h> #include <objtool/arch.h> #include <objtool/warn.h> -#include <objtool/endianness.h> #include <objtool/builtin.h> #include <arch/elf.h> -int arch_ftrace_match(char *name) +const char *arch_reg_name[CFI_NUM_REGS] = { + "rax", "rcx", "rdx", "rbx", + "rsp", "rbp", "rsi", "rdi", + "r8", "r9", "r10", "r11", + "r12", "r13", "r14", "r15", + "ra" +}; + +int arch_ftrace_match(const char *name) { return !strcmp(name, "__fentry__"); } @@ -68,9 +76,65 @@ bool arch_callee_saved_reg(unsigned char reg) } } -unsigned long arch_dest_reloc_offset(int addend) +/* Undo the effects of __pa_symbol() if necessary */ +static unsigned long phys_to_virt(unsigned long pa) +{ + s64 va = pa; + + if (va > 0) + va &= ~(0x80000000); + + return va; +} + +s64 arch_insn_adjusted_addend(struct instruction *insn, struct reloc *reloc) +{ + s64 addend = reloc_addend(reloc); + + if (arch_pc_relative_reloc(reloc)) + addend += insn->offset + insn->len - reloc_offset(reloc); + + return phys_to_virt(addend); +} + +static void scan_for_insn(struct section *sec, unsigned long offset, + unsigned long *insn_off, unsigned int *insn_len) { - return addend + 4; + unsigned long o = 0; + struct insn insn; + + while (1) { + + insn_decode(&insn, sec->data->d_buf + o, sec_size(sec) - o, + INSN_MODE_64); + + if (o + insn.length > offset) { + *insn_off = o; + *insn_len = insn.length; + return; + } + + o += insn.length; + } +} + +u64 arch_adjusted_addend(struct reloc *reloc) +{ + unsigned int type = reloc_type(reloc); + s64 addend = reloc_addend(reloc); + unsigned long insn_off; + unsigned int insn_len; + + if (type == R_X86_64_PLT32) + return addend + 4; + + if (type != R_X86_64_PC32 || !is_text_sec(reloc->sec->base)) + return addend; + + scan_for_insn(reloc->sec->base, reloc_offset(reloc), + &insn_off, &insn_len); + + return addend + insn_off + insn_len - reloc_offset(reloc); } unsigned long arch_jump_destination(struct instruction *insn) @@ -189,15 +253,6 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec op2 = ins.opcode.bytes[1]; op3 = ins.opcode.bytes[2]; - /* - * XXX hack, decoder is buggered and thinks 0xea is 7 bytes long. - */ - if (op1 == 0xea) { - insn->len = 1; - insn->type = INSN_BUG; - return 0; - } - if (ins.rex_prefix.nbytes) { rex = ins.rex_prefix.bytes[0]; rex_w = X86_REX_W(rex) >> 3; @@ -503,6 +558,12 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec break; case 0x90: + if (rex_b) /* XCHG %r8, %rax */ + break; + + if (prefix == 0xf3) /* REP NOP := PAUSE */ + break; + insn->type = INSN_NOP; break; @@ -556,13 +617,14 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec } else if (op2 == 0x0b || op2 == 0xb9) { - /* ud2 */ + /* ud2, ud1 */ insn->type = INSN_BUG; - } else if (op2 == 0x0d || op2 == 0x1f) { + } else if (op2 == 0x1f) { - /* nopl/nopw */ - insn->type = INSN_NOP; + /* 0f 1f /0 := NOPL */ + if (modrm_reg == 0) + insn->type = INSN_NOP; } else if (op2 == 0x1e) { @@ -692,6 +754,10 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec insn->type = INSN_SYSRET; break; + case 0xd6: /* udb */ + insn->type = INSN_BUG; + break; + case 0xe0: /* loopne */ case 0xe1: /* loope */ case 0xe2: /* loop */ @@ -892,3 +958,14 @@ bool arch_absolute_reloc(struct elf *elf, struct reloc *reloc) return false; } } + +#ifdef DISAS + +int arch_disas_info_init(struct disassemble_info *dinfo) +{ + return disas_info_init(dinfo, bfd_arch_i386, + bfd_mach_i386_i386, bfd_mach_x86_64, + "att"); +} + +#endif /* DISAS */ |