diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 80 |
1 files changed, 40 insertions, 40 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index c1d9116..7466aba 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -73,11 +73,12 @@ #define MemAbs (1<<11) /* Memory operand is absolute displacement */ #define String (1<<12) /* String instruction (rep capable) */ #define Stack (1<<13) /* Stack instruction (push/pop) */ +#define GroupMask (7<<14) /* Opcode uses one of the group mechanisms */ #define Group (1<<14) /* Bits 3:5 of modrm byte extend opcode */ -#define GroupDual (1<<15) /* Alternate decoding of mod == 3 */ -#define Prefix (1<<16) /* Instruction varies with 66/f2/f3 prefix */ +#define GroupDual (2<<14) /* Alternate decoding of mod == 3 */ +#define Prefix (3<<14) /* Instruction varies with 66/f2/f3 prefix */ +#define RMExt (4<<14) /* Opcode extension in ModRM r/m if mod == 3 */ #define Sse (1<<17) /* SSE Vector instruction */ -#define RMExt (1<<18) /* Opcode extension in ModRM r/m if mod == 3 */ /* Misc flags */ #define Prot (1<<21) /* instruction generates #UD if not in prot-mode */ #define VendorSpecific (1<<22) /* Vendor specific instruction */ @@ -2969,7 +2970,7 @@ static int check_perm_out(struct x86_emulate_ctxt *ctxt) #define N D(0) #define EXT(_f, _e) { .flags = ((_f) | RMExt), .u.group = (_e) } #define G(_f, _g) { .flags = ((_f) | Group), .u.group = (_g) } -#define GD(_f, _g) { .flags = ((_f) | Group | GroupDual), .u.gdual = (_g) } +#define GD(_f, _g) { .flags = ((_f) | GroupDual), .u.gdual = (_g) } #define I(_f, _e) { .flags = (_f), .u.execute = (_e) } #define II(_f, _e, _i) \ { .flags = (_f), .u.execute = (_e), .intercept = x86_intercept_##_i } @@ -3337,9 +3338,9 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) struct decode_cache *c = &ctxt->decode; int rc = X86EMUL_CONTINUE; int mode = ctxt->mode; - int def_op_bytes, def_ad_bytes, dual, goffset, simd_prefix; + int def_op_bytes, def_ad_bytes, goffset, simd_prefix; bool op_prefix = false; - struct opcode opcode, *g_mod012, *g_mod3; + struct opcode opcode; struct operand memop = { .type = OP_NONE }; c->eip = ctxt->eip; @@ -3433,44 +3434,43 @@ done_prefixes: } c->d = opcode.flags; - if (c->d & Group) { - dual = c->d & GroupDual; - c->modrm = insn_fetch(u8, 1, c->eip); - --c->eip; - - if (c->d & GroupDual) { - g_mod012 = opcode.u.gdual->mod012; - g_mod3 = opcode.u.gdual->mod3; - } else - g_mod012 = g_mod3 = opcode.u.group; - - c->d &= ~(Group | GroupDual); - - goffset = (c->modrm >> 3) & 7; - - if ((c->modrm >> 6) == 3) - opcode = g_mod3[goffset]; - else - opcode = g_mod012[goffset]; - - if (opcode.flags & RMExt) { + while (c->d & GroupMask) { + switch (c->d & GroupMask) { + case Group: + c->modrm = insn_fetch(u8, 1, c->eip); + --c->eip; + goffset = (c->modrm >> 3) & 7; + opcode = opcode.u.group[goffset]; + break; + case GroupDual: + c->modrm = insn_fetch(u8, 1, c->eip); + --c->eip; + goffset = (c->modrm >> 3) & 7; + if ((c->modrm >> 6) == 3) + opcode = opcode.u.gdual->mod3[goffset]; + else + opcode = opcode.u.gdual->mod012[goffset]; + break; + case RMExt: goffset = c->modrm & 7; opcode = opcode.u.group[goffset]; - } - - c->d |= opcode.flags; - } - - if (c->d & Prefix) { - if (c->rep_prefix && op_prefix) + break; + case Prefix: + if (c->rep_prefix && op_prefix) + return X86EMUL_UNHANDLEABLE; + simd_prefix = op_prefix ? 0x66 : c->rep_prefix; + switch (simd_prefix) { + case 0x00: opcode = opcode.u.gprefix->pfx_no; break; + case 0x66: opcode = opcode.u.gprefix->pfx_66; break; + case 0xf2: opcode = opcode.u.gprefix->pfx_f2; break; + case 0xf3: opcode = opcode.u.gprefix->pfx_f3; break; + } + break; + default: return X86EMUL_UNHANDLEABLE; - simd_prefix = op_prefix ? 0x66 : c->rep_prefix; - switch (simd_prefix) { - case 0x00: opcode = opcode.u.gprefix->pfx_no; break; - case 0x66: opcode = opcode.u.gprefix->pfx_66; break; - case 0xf2: opcode = opcode.u.gprefix->pfx_f2; break; - case 0xf3: opcode = opcode.u.gprefix->pfx_f3; break; } + + c->d &= ~GroupMask; c->d |= opcode.flags; } |