diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c
index 8511bfc62963..56173beecbc6 100644
--- a/drivers/scsi/xen-scsifront.c
+++ b/drivers/scsi/xen-scsifront.c
@@ -83,6 +83,8 @@ struct vscsifrnt_shadow {
 	uint16_t rqid;
 	uint16_t ref_rqid;
 
+	bool inflight;
+
 	unsigned int nr_grants;		/* number of grants in gref[] */
 	struct scsiif_request_segment *sg;	/* scatter/gather elements */
 	struct scsiif_request_segment seg[VSCSIIF_SG_TABLESIZE];
@@ -104,7 +106,11 @@ struct vscsifrnt_info {
 	struct xenbus_device *dev;
 
 	struct Scsi_Host *host;
-	int host_active;
+	enum {
+		STATE_INACTIVE,
+		STATE_ACTIVE,
+		STATE_ERROR
+	}  host_active;
 
 	unsigned int evtchn;
 	unsigned int irq;
@@ -217,6 +223,8 @@ static int scsifront_do_request(struct vscsifrnt_info *info,
 	for (i = 0; i < (shadow->nr_segments & ~VSCSIIF_SG_GRANT); i++)
 		ring_req->seg[i] = shadow->seg[i];
 
+	shadow->inflight = true;
+
 	RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(ring, notify);
 	if (notify)
 		notify_remote_via_irq(info->irq);
@@ -224,6 +232,13 @@ static int scsifront_do_request(struct vscsifrnt_info *info,
 	return 0;
 }
 
+static void scsifront_set_error(struct vscsifrnt_info *info, const char *msg)
+{
+	shost_printk(KERN_ERR, info->host, KBUILD_MODNAME "%s\n"
+		     "Disabling device for further use\n", msg);
+	info->host_active = STATE_ERROR;
+}
+
 static void scsifront_gnttab_done(struct vscsifrnt_info *info,
 				  struct vscsifrnt_shadow *shadow)
 {
@@ -234,9 +249,8 @@ static void scsifront_gnttab_done(struct vscsifrnt_info *info,
 
 	for (i = 0; i < shadow->nr_grants; i++) {
 		if (unlikely(!gnttab_try_end_foreign_access(shadow->gref[i]))) {
-			shost_printk(KERN_ALERT, info->host, KBUILD_MODNAME
-				     "grant still in use by backend\n");
-			BUG();
+			scsifront_set_error(info, "grant still in use by backend");
+			return;
 		}
 	}
 
@@ -308,6 +322,8 @@ static void scsifront_cdb_cmd_done(struct vscsifrnt_info *info,
 	BUG_ON(sc == NULL);
 
 	scsifront_gnttab_done(info, shadow);
+	if (info->host_active == STATE_ERROR)
+		return;
 	scsifront_put_rqid(info, id);
 
 	set_host_byte(sc, scsifront_host_byte(ring_rsp->rslt));
@@ -348,9 +364,7 @@ static void scsifront_sync_cmd_done(struct vscsifrnt_info *info,
 			scsifront_wake_up(info);
 		return;
 	default:
-		shost_printk(KERN_ERR, info->host, KBUILD_MODNAME
-			     "bad reset state %d, possibly leaking %u\n",
-			     shadow->rslt_reset, id);
+		scsifront_set_error(info, "bad reset state");
 		break;
 	}
 	spin_unlock_irqrestore(&info->shadow_lock, flags);
@@ -361,28 +375,41 @@ static void scsifront_sync_cmd_done(struct vscsifrnt_info *info,
 static void scsifront_do_response(struct vscsifrnt_info *info,
 				  struct vscsiif_response *ring_rsp)
 {
-	if (WARN(ring_rsp->rqid >= VSCSIIF_MAX_REQS ||
-		 test_bit(ring_rsp->rqid, info->shadow_free_bitmap),
-		 "illegal rqid %u returned by backend!\n", ring_rsp->rqid))
+	struct vscsifrnt_shadow *shadow;
+
+	if (ring_rsp->rqid >= VSCSIIF_MAX_REQS ||
+	    !info->shadow[ring_rsp->rqid]->inflight) {
+		scsifront_set_error(info, "illegal rqid returned by backend!");
 		return;
+	}
+	shadow = info->shadow[ring_rsp->rqid];
+	shadow->inflight = false;
 
-	if (info->shadow[ring_rsp->rqid]->act == VSCSIIF_ACT_SCSI_CDB)
+	if (shadow->act == VSCSIIF_ACT_SCSI_CDB)
 		scsifront_cdb_cmd_done(info, ring_rsp);
 	else
 		scsifront_sync_cmd_done(info, ring_rsp);
 }
 
-static int scsifront_ring_drain(struct vscsifrnt_info *info)
+static int scsifront_ring_drain(struct vscsifrnt_info *info,
+				unsigned int *eoiflag)
 {
-	struct vscsiif_response *ring_rsp;
+	struct vscsiif_response ring_rsp;
 	RING_IDX i, rp;
 	int more_to_do = 0;
 
-	rp = info->ring.sring->rsp_prod;
-	rmb();	/* ordering required respective to dom0 */
+	rp = READ_ONCE(info->ring.sring->rsp_prod);
+	virt_rmb();	/* ordering required respective to backend */
+	if (RING_RESPONSE_PROD_OVERFLOW(&info->ring, rp)) {
+		scsifront_set_error(info, "illegal number of responses");
+		return 0;
+	}
 	for (i = info->ring.rsp_cons; i != rp; i++) {
-		ring_rsp = RING_GET_RESPONSE(&info->ring, i);
-		scsifront_do_response(info, ring_rsp);
+		RING_COPY_RESPONSE(&info->ring, i, &ring_rsp);
+		scsifront_do_response(info, &ring_rsp);
+		if (info->host_active == STATE_ERROR)
+			return 0;
+		*eoiflag &= ~XEN_EOI_FLAG_SPURIOUS;
 	}
 
 	info->ring.rsp_cons = i;
@@ -395,14 +422,15 @@ static int scsifront_ring_drain(struct vscsifrnt_info *info)
 	return more_to_do;
 }
 
-static int scsifront_cmd_done(struct vscsifrnt_info *info)
+static int scsifront_cmd_done(struct vscsifrnt_info *info,
+			      unsigned int *eoiflag)
 {
 	int more_to_do;
 	unsigned long flags;
 
 	spin_lock_irqsave(info->host->host_lock, flags);
 
-	more_to_do = scsifront_ring_drain(info);
+	more_to_do = scsifront_ring_drain(info, eoiflag);
 
 	info->wait_ring_available = 0;
 
@@ -416,20 +444,28 @@ static int scsifront_cmd_done(struct vscsifrnt_info *info)
 static irqreturn_t scsifront_irq_fn(int irq, void *dev_id)
 {
 	struct vscsifrnt_info *info = dev_id;
+	unsigned int eoiflag = XEN_EOI_FLAG_SPURIOUS;
+
+	if (info->host_active == STATE_ERROR) {
+		xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS);
+		return IRQ_HANDLED;
+	}
 
-	while (scsifront_cmd_done(info))
+	while (scsifront_cmd_done(info, &eoiflag))
 		/* Yield point for this unbounded loop. */
 		cond_resched();
 
+	xen_irq_lateeoi(irq, eoiflag);
+
 	return IRQ_HANDLED;
 }
 
 static void scsifront_finish_all(struct vscsifrnt_info *info)
 {
-	unsigned i;
+	unsigned int i, dummy;
 	struct vscsiif_response resp;
 
-	scsifront_ring_drain(info);
+	scsifront_ring_drain(info, &dummy);
 
 	for (i = 0; i < VSCSIIF_MAX_REQS; i++) {
 		if (test_bit(i, info->shadow_free_bitmap))
@@ -586,6 +622,9 @@ static int scsifront_queuecommand(struct Scsi_Host *shost,
 	unsigned long flags;
 	int err;
 
+	if (info->host_active == STATE_ERROR)
+		return SCSI_MLQUEUE_HOST_BUSY;
+
 	sc->result = 0;
 
 	shadow->sc  = sc;
@@ -638,6 +677,9 @@ static int scsifront_action_handler(struct scsi_cmnd *sc, uint8_t act)
 	struct vscsifrnt_shadow *shadow, *s = scsi_cmd_priv(sc);
 	int err = 0;
 
+	if (info->host_active == STATE_ERROR)
+		return FAILED;
+
 	shadow = kzalloc(sizeof(*shadow), GFP_NOIO);
 	if (!shadow)
 		return FAILED;
@@ -709,6 +751,9 @@ static int scsifront_sdev_configure(struct scsi_device *sdev)
 	struct vscsifrnt_info *info = shost_priv(sdev->host);
 	int err;
 
+	if (info->host_active == STATE_ERROR)
+		return -EIO;
+
 	if (info && current == info->curr) {
 		err = xenbus_printf(XBT_NIL, info->dev->nodename,
 			      info->dev_state_path, "%d", XenbusStateConnected);
@@ -784,7 +829,7 @@ static int scsifront_alloc_ring(struct vscsifrnt_info *info)
 		goto free_gnttab;
 	}
 
-	err = bind_evtchn_to_irq(info->evtchn);
+	err = bind_evtchn_to_irq_lateeoi(info->evtchn);
 	if (err <= 0) {
 		xenbus_dev_fatal(dev, err, "bind_evtchn_to_irq");
 		goto free_gnttab;
@@ -914,7 +959,7 @@ static int scsifront_probe(struct xenbus_device *dev,
 		goto free_sring;
 	}
 	info->host = host;
-	info->host_active = 1;
+	info->host_active = STATE_ACTIVE;
 
 	xenbus_switch_state(dev, XenbusStateInitialised);
 
@@ -982,10 +1027,10 @@ static int scsifront_remove(struct xenbus_device *dev)
 	pr_debug("%s: %s removed\n", __func__, dev->nodename);
 
 	mutex_lock(&scsifront_mutex);
-	if (info->host_active) {
+	if (info->host_active != STATE_INACTIVE) {
 		/* Scsi_host not yet removed */
 		scsi_remove_host(info->host);
-		info->host_active = 0;
+		info->host_active = STATE_INACTIVE;
 	}
 	mutex_unlock(&scsifront_mutex);
 
@@ -1009,9 +1054,9 @@ static void scsifront_disconnect(struct vscsifrnt_info *info)
 	 */
 
 	mutex_lock(&scsifront_mutex);
-	if (info->host_active) {
+	if (info->host_active != STATE_INACTIVE) {
 		scsi_remove_host(host);
-		info->host_active = 0;
+		info->host_active = STATE_INACTIVE;
 	}
 	mutex_unlock(&scsifront_mutex);
 
@@ -1029,6 +1074,9 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op)
 	unsigned int hst, chn, tgt, lun;
 	struct scsi_device *sdev;
 
+	if (info->host_active == STATE_ERROR)
+		return;
+
 	dir = xenbus_directory(XBT_NIL, dev->otherend, "vscsi-devs", &dir_n);
 	if (IS_ERR(dir))
 		return;
