KVM: emulator: emulate XLAT

This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1.
It is just a MOV in disguise, with a funny source address.

Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
This commit is contained in:
Paolo Bonzini 2013-05-09 11:32:50 +02:00 committed by Gleb Natapov
parent a035d5c64d
commit 7fa57952d7
1 changed files with 14 additions and 1 deletions
arch/x86/kvm

View File

@ -60,6 +60,7 @@
#define OpGS 25ull /* GS */
#define OpMem8 26ull /* 8-bit zero extended memory operand */
#define OpImm64 27ull /* Sign extended 16/32/64-bit immediate */
#define OpXLat 28ull /* memory at BX/EBX/RBX + zero-extended AL */
#define OpBits 5 /* Width of operand field */
#define OpMask ((1ull << OpBits) - 1)
@ -99,6 +100,7 @@
#define SrcImmUByte (OpImmUByte << SrcShift)
#define SrcImmU (OpImmU << SrcShift)
#define SrcSI (OpSI << SrcShift)
#define SrcXLat (OpXLat << SrcShift)
#define SrcImmFAddr (OpImmFAddr << SrcShift)
#define SrcMemFAddr (OpMemFAddr << SrcShift)
#define SrcAcc (OpAcc << SrcShift)
@ -3959,7 +3961,8 @@ static const struct opcode opcode_table[256] = {
G(Src2One | ByteOp, group2), G(Src2One, group2),
G(Src2CL | ByteOp, group2), G(Src2CL, group2),
I(DstAcc | SrcImmUByte | No64, em_aam),
I(DstAcc | SrcImmUByte | No64, em_aad), N, N,
I(DstAcc | SrcImmUByte | No64, em_aad), N,
I(DstAcc | SrcXLat | ByteOp, em_mov),
/* 0xD8 - 0xDF */
N, E(0, &escape_d9), N, E(0, &escape_db), N, E(0, &escape_dd), N, N,
/* 0xE0 - 0xE7 */
@ -4221,6 +4224,16 @@ static int decode_operand(struct x86_emulate_ctxt *ctxt, struct operand *op,
op->val = 0;
op->count = 1;
break;
case OpXLat:
op->type = OP_MEM;
op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
op->addr.mem.ea =
register_address(ctxt,
reg_read(ctxt, VCPU_REGS_RBX) +
(reg_read(ctxt, VCPU_REGS_RAX) & 0xff));
op->addr.mem.seg = seg_override(ctxt);
op->val = 0;
break;
case OpImmFAddr:
op->type = OP_IMM;
op->addr.mem.ea = ctxt->_eip;