diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 8079d141792af9..b4a87debbb4b3b 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -5000,6 +5000,8 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
 	bool op_prefix = false;
 	bool has_seg_override = false;
 	struct opcode opcode;
+	u16 dummy;
+	struct desc_struct desc;
 
 	ctxt->memop.type = OP_NONE;
 	ctxt->memopp = NULL;
@@ -5018,6 +5020,11 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
 	switch (mode) {
 	case X86EMUL_MODE_REAL:
 	case X86EMUL_MODE_VM86:
+		def_op_bytes = def_ad_bytes = 2;
+		ctxt->ops->get_segment(ctxt, &dummy, &desc, NULL, VCPU_SREG_CS);
+		if (desc.d)
+			def_op_bytes = def_ad_bytes = 4;
+		break;
 	case X86EMUL_MODE_PROT16:
 		def_op_bytes = def_ad_bytes = 2;
 		break;