diff --git a/hw/s390x/css.c b/hw/s390x/css.c
index cc76c537da..599805d275 100644
--- a/hw/s390x/css.c
+++ b/hw/s390x/css.c
@@ -433,6 +433,11 @@ static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr,
         return -EINVAL;
     }
 
+    /* We don't support MIDA. */
+    if (ccw.flags & CCW_FLAG_MIDA) {
+        return -EINVAL;
+    }
+
     if (ccw.flags & CCW_FLAG_SUSPEND) {
         return suspend_allowed ? -EINPROGRESS : -EINVAL;
     }
diff --git a/include/hw/s390x/ioinst.h b/include/hw/s390x/ioinst.h
index c559f53426..92d15655e4 100644
--- a/include/hw/s390x/ioinst.h
+++ b/include/hw/s390x/ioinst.h
@@ -182,6 +182,7 @@ typedef struct CCW1 {
 #define CCW_FLAG_PCI             0x08
 #define CCW_FLAG_IDA             0x04
 #define CCW_FLAG_SUSPEND         0x02
+#define CCW_FLAG_MIDA            0x01
 
 #define CCW_CMD_NOOP             0x03
 #define CCW_CMD_BASIC_SENSE      0x04
diff --git a/target/s390x/ioinst.c b/target/s390x/ioinst.c
index 62a777100c..d5e6b8066b 100644
--- a/target/s390x/ioinst.c
+++ b/target/s390x/ioinst.c
@@ -201,6 +201,10 @@ static int ioinst_orb_valid(ORB *orb)
         (orb->ctrl1 & ORB_CTRL1_MASK_INVALID)) {
         return 0;
     }
+    /* We don't support MIDA. */
+    if (orb->ctrl1 & ORB_CTRL1_MASK_MIDAW) {
+        return 0;
+    }
     if ((orb->cpa & HIGH_ORDER_BIT) != 0) {
         return 0;
     }