Commit d8769fed authored by Mohammed Gamal's avatar Mohammed Gamal Committed by Avi Kivity
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KVM: x86 emulator: Introduce No64 decode option 



Introduces a new decode option "No64", which is used for instructions that are
invalid in long mode.

Signed-off-by: default avatarMohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 0934ac9d

arch/x86/kvm/emulate.c

+14 −28
Original line number Diff line number Diff line
@@ -75,6 +75,8 @@ 
#define Group       (1<<14)     /* Bits 3:5 of modrm byte extend opcode */

#define GroupDual   (1<<15)     /* Alternate decoding of mod == 3 */

#define GroupMask   0xff        /* Group number stored in bits 0:7 */

/* Misc flags */

#define No64	    (1<<28)

/* Source 2 operand type */

#define Src2None    (0<<29)

#define Src2CL      (1<<29)
@@ -93,21 +95,21 @@ static u32 opcode_table[256] = { 
	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,

	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,

	ByteOp | DstAcc | SrcImm, DstAcc | SrcImm,

	ImplicitOps | Stack, ImplicitOps | Stack,

	ImplicitOps | Stack | No64, ImplicitOps | Stack | No64,

	/* 0x08 - 0x0F */

	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,

	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,

	0, 0, ImplicitOps | Stack, 0,

	0, 0, ImplicitOps | Stack | No64, 0,

	/* 0x10 - 0x17 */

	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,

	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,

	ByteOp | DstAcc | SrcImm, DstAcc | SrcImm,

	ImplicitOps | Stack, ImplicitOps | Stack,

	ImplicitOps | Stack | No64, ImplicitOps | Stack | No64,

	/* 0x18 - 0x1F */

	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,

	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,

	ByteOp | DstAcc | SrcImm, DstAcc | SrcImm,

	ImplicitOps | Stack, ImplicitOps | Stack,

	ImplicitOps | Stack | No64, ImplicitOps | Stack | No64,

	/* 0x20 - 0x27 */

	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,

	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
@@ -161,7 +163,7 @@ static u32 opcode_table[256] = { 
	/* 0x90 - 0x97 */

	DstReg, DstReg, DstReg, DstReg,	DstReg, DstReg, DstReg, DstReg,

	/* 0x98 - 0x9F */

	0, 0, SrcImm | Src2Imm16, 0,

	0, 0, SrcImm | Src2Imm16 | No64, 0,

	ImplicitOps | Stack, ImplicitOps | Stack, 0, 0,

	/* 0xA0 - 0xA7 */

	ByteOp | DstReg | SrcMem | Mov | MemAbs, DstReg | SrcMem | Mov | MemAbs,
@@ -188,7 +190,7 @@ static u32 opcode_table[256] = { 
	ByteOp | DstMem | SrcImm | ModRM | Mov, DstMem | SrcImm | ModRM | Mov,

	/* 0xC8 - 0xCF */

	0, 0, 0, ImplicitOps | Stack,

	ImplicitOps, SrcImmByte, ImplicitOps, ImplicitOps,

	ImplicitOps, SrcImmByte, ImplicitOps | No64, ImplicitOps,

	/* 0xD0 - 0xD7 */

	ByteOp | DstMem | SrcImplicit | ModRM, DstMem | SrcImplicit | ModRM,

	ByteOp | DstMem | SrcImplicit | ModRM, DstMem | SrcImplicit | ModRM,
@@ -201,7 +203,7 @@ static u32 opcode_table[256] = { 
	ByteOp | SrcImmUByte, SrcImmUByte,

	/* 0xE8 - 0xEF */

	SrcImm | Stack, SrcImm | ImplicitOps,

	SrcImmU | Src2Imm16, SrcImmByte | ImplicitOps,

	SrcImmU | Src2Imm16 | No64, SrcImmByte | ImplicitOps,

	SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,

	SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,

	/* 0xF0 - 0xF7 */
@@ -967,6 +969,11 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		}

	}



	if (mode == X86EMUL_MODE_PROT64 && (c->d & No64)) {

		kvm_report_emulation_failure(ctxt->vcpu, "invalid x86/64 instruction");;

		return -1;

	}



	if (c->d & Group) {

		group = c->d & GroupMask;

		c->modrm = insn_fetch(u8, 1, c->eip);
@@ -1739,15 +1746,9 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags);

		break;

	case 0x06:		/* push es */

		if (ctxt->mode == X86EMUL_MODE_PROT64)

			goto cannot_emulate;



		emulate_push_sreg(ctxt, VCPU_SREG_ES);

		break;

	case 0x07:		/* pop es */

                if (ctxt->mode == X86EMUL_MODE_PROT64)

                        goto cannot_emulate;



		rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_ES);

		if (rc != 0)

			goto done;
@@ -1757,9 +1758,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags);

		break;

	case 0x0e:		/* push cs */

                if (ctxt->mode == X86EMUL_MODE_PROT64)

                        goto cannot_emulate;



		emulate_push_sreg(ctxt, VCPU_SREG_CS);

		break;

	case 0x10 ... 0x15:
@@ -1767,15 +1765,9 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		emulate_2op_SrcV("adc", c->src, c->dst, ctxt->eflags);

		break;

	case 0x16:		/* push ss */

                if (ctxt->mode == X86EMUL_MODE_PROT64)

                        goto cannot_emulate;



		emulate_push_sreg(ctxt, VCPU_SREG_SS);

		break;

	case 0x17:		/* pop ss */

                if (ctxt->mode == X86EMUL_MODE_PROT64)

                        goto cannot_emulate;



		rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_SS);

		if (rc != 0)

			goto done;
@@ -1785,15 +1777,9 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		emulate_2op_SrcV("sbb", c->src, c->dst, ctxt->eflags);

		break;

	case 0x1e:		/* push ds */

                if (ctxt->mode == X86EMUL_MODE_PROT64)

                        goto cannot_emulate;



		emulate_push_sreg(ctxt, VCPU_SREG_DS);

		break;

	case 0x1f:		/* pop ds */

                if (ctxt->mode == X86EMUL_MODE_PROT64)

                        goto cannot_emulate;



		rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_DS);

		if (rc != 0)

			goto done;