diff options
Diffstat (limited to 'drivers/kvm/x86_emulate.c')
| -rw-r--r-- | drivers/kvm/x86_emulate.c | 77 |
1 files changed, 53 insertions, 24 deletions
diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c index d7026cb8fc7..540589c5d42 100644 --- a/drivers/kvm/x86_emulate.c +++ b/drivers/kvm/x86_emulate.c @@ -517,20 +517,16 @@ static int test_cc(unsigned int condition, unsigned int flags) } int -x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) +x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) { struct decode_cache *c = &ctxt->decode; u8 sib, rex_prefix = 0; unsigned int i; int rc = 0; - unsigned long cr2 = ctxt->cr2; int mode = ctxt->mode; int index_reg = 0, base_reg = 0, scale, rip_relative = 0; - int no_wb = 0; - u64 msr_data; /* Shadow copy of register state. Committed on successful emulation. */ - unsigned long _eflags = ctxt->eflags; memset(c, 0, sizeof(struct decode_cache)); c->eip = ctxt->vcpu->rip; @@ -622,8 +618,10 @@ done_prefixes: } /* Unrecognised? */ - if (c->d == 0) - goto cannot_emulate; + if (c->d == 0) { + DPRINTF("Cannot emulate %02x\n", c->b); + return -1; + } } /* ModRM and SIB bytes. */ @@ -776,7 +774,6 @@ done_prefixes: } if (c->ad_bytes != 8) c->modrm_ea = (u32)c->modrm_ea; - cr2 = c->modrm_ea; modrm_done: ; } @@ -838,13 +835,6 @@ done_prefixes: break; } c->src.type = OP_MEM; - c->src.ptr = (unsigned long *)cr2; - c->src.val = 0; - if ((rc = ops->read_emulated((unsigned long)c->src.ptr, - &c->src.val, - c->src.bytes, ctxt->vcpu)) != 0) - goto done; - c->src.orig_val = c->src.val; break; case SrcImm: c->src.type = OP_IMM; @@ -877,7 +867,7 @@ done_prefixes: switch (c->d & DstMask) { case ImplicitOps: /* Special instructions do their own operand decoding. */ - goto special_insn; + return 0; case DstReg: c->dst.type = OP_REG; if ((c->d & ByteOp) @@ -905,14 +895,54 @@ done_prefixes: } break; case DstMem: - c->dst.type = OP_MEM; - c->dst.ptr = (unsigned long *)cr2; - c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; - c->dst.val = 0; if ((c->d & ModRM) && c->modrm_mod == 3) { c->dst.type = OP_REG; break; } + c->dst.type = OP_MEM; + break; + } + +done: + return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0; +} + +int +x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) +{ + unsigned long cr2 = ctxt->cr2; + int no_wb = 0; + u64 msr_data; + unsigned long _eflags = ctxt->eflags; + struct decode_cache *c = &ctxt->decode; + int rc; + + rc = x86_decode_insn(ctxt, ops); + if (rc) + return rc; + + if ((c->d & ModRM) && (c->modrm_mod != 3)) + cr2 = c->modrm_ea; + + if (c->src.type == OP_MEM) { + c->src.ptr = (unsigned long *)cr2; + c->src.val = 0; + if ((rc = ops->read_emulated((unsigned long)c->src.ptr, + &c->src.val, + c->src.bytes, + ctxt->vcpu)) != 0) + goto done; + c->src.orig_val = c->src.val; + } + + if ((c->d & DstMask) == ImplicitOps) + goto special_insn; + + + if (c->dst.type == OP_MEM) { + c->dst.ptr = (unsigned long *)cr2; + c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; + c->dst.val = 0; if (c->d & BitOp) { unsigned long mask = ~(c->dst.bytes * 8 - 1); @@ -925,7 +955,6 @@ done_prefixes: &c->dst.val, c->dst.bytes, ctxt->vcpu)) != 0)) goto done; - break; } c->dst.orig_val = c->dst.val; @@ -983,7 +1012,7 @@ done_prefixes: emulate_2op_SrcV("cmp", c->src, c->dst, _eflags); break; case 0x63: /* movsxd */ - if (mode != X86EMUL_MODE_PROT64) + if (ctxt->mode != X86EMUL_MODE_PROT64) goto cannot_emulate; c->dst.val = (s32) c->src.val; break; @@ -1041,7 +1070,7 @@ done_prefixes: break; case 0x8f: /* pop (sole member of Grp1a) */ /* 64-bit mode: POP always pops a 64-bit operand. */ - if (mode == X86EMUL_MODE_PROT64) + if (ctxt->mode == X86EMUL_MODE_PROT64) c->dst.bytes = 8; if ((rc = ops->read_std(register_address( ctxt->ss_base, @@ -1152,7 +1181,7 @@ done_prefixes: break; case 6: /* push */ /* 64-bit mode: PUSH always pushes a 64-bit operand. */ - if (mode == X86EMUL_MODE_PROT64) { + if (ctxt->mode == X86EMUL_MODE_PROT64) { c->dst.bytes = 8; if ((rc = ops->read_std( (unsigned long)c->dst.ptr, |