@@ -1954,8 +1954,7 @@ x86_decode_twobyte(
case 0x50 ... 0x77:
case 0x79 ... 0x7f:
case 0xae:
- case 0xc2:
- case 0xc4 ... 0xc6:
+ case 0xc2 ... 0xc6:
case 0xd0 ... 0xfe:
ctxt->opcode |= MASK_INSR(vex.pfx, X86EMUL_OPC_PFX_MASK);
break;
@@ -2461,8 +2460,8 @@ x86_decode(
}
/*
- * Undo the operand-size override effect of prefix 66 when it was
- * determined to have another meaning.
+ * When prefix 66 has a meaning different from operand-size override,
+ * operand size defaults to 4 and can't be overridden to 2.
*/
if ( op_bytes == 2 &&
(ctxt->opcode & X86EMUL_OPC_PFX_MASK) == X86EMUL_OPC_66(0, 0) )
@@ -5291,7 +5290,6 @@ x86_emulate(
case X86EMUL_OPC(0x0f, 0xc3): /* movnti */
/* Ignore the non-temporal hint for now. */
vcpu_must_have(sse2);
- generate_exception_if(dst.bytes <= 2, EXC_UD);
dst.val = src.val;
break;